Artemisia princeps, Artemisia japonica (Western Artemisia), Artemisia rupestris (Bitter Artemisia), and Artemisia velutipes (Matricaria) all belong to the Artemisia genus of the Asteraceae family. Many species are extremely common perennial herbs that grow dominantly in small vacant lots from urban areas to mountainous fields. A major characteristic is that the underside of the leaves is cottony and fluffy, and unusually for the Asteraceae family, they are wind-pollinated. However, because their flowers and fruits are inconspicuous, classification is difficult, and they can be hard to distinguish in the wild. The Artemisia genus is a very large group, so you need to consult a field guide for accurate identification, but for the four species, you can roughly distinguish them by the shape of the leaves and the amount of hair. Three of the species are rare on Honshu, with Artemisia princeps being almost dominant. Nowadays, their use seems to be limited to mugwort rice cakes, but Artemisia japonica is commonly used in Okinawa, and the group is actively researched for its medicinal properties. It can also be used in moxibustion. This article will explain the classification, morphology, ecology, and uses of the Artemisia genus.

What are mugwort, wormwood (Artemisia princeps), bitter wormwood, and male wormwood?

Artemisia indica var. maximowiczii, also known as mugwort, is also called Kazuzaki mugwort or mochigusa. While Artemisia princeps is sometimes seen used online, it is a synonym (former scientific name). It is a perennial herb distributed in Honshu, Shikoku, Kyushu, and the Ogasawara Islands of Japan, as well as in Korea, and grows in a wide range of areas from urban centers to mountains and fields (Kanagawa Prefecture Flora Survey Association, 2018).

Artemisia indica var. indica, also known as Okinawa mugwort or Fuchiba, is a perennial herb distributed in Honshu (west of the Kanto region), Kyushu, and the Ryukyu Islands in Japan; Korea, China, Taiwan, Southeast Asia (Thailand, Cambodia, Myanmar, Vietnam, Philippines), and South Asia, growing in areas such as construction sites and slopes along forest roads (Shimotsuke, 2014).

Artemisia absinthium, also known as bitter wormwood, is a perennial plant native to Europe, Russia, the Caucasus, West Asia, and North America, and has escaped cultivation and become naturalized all over the world, including Japan.

Artemisia japonica subsp. japonica var. japonica, also known as male mugwort, is a perennial herb distributed in Hokkaido, Honshu, Shikoku, Kyushu, and the Ryukyu Islands in Japan; as well as in Korea, China, Taiwan, the Philippines, and Afghanistan. It grows in riverbeds, grasslands, forest edges, and railway embankments. Its Japanese name is said to originate from the small size of its seeds.

All of these belong to the Artemisia genus of the Asteraceae family, and are extremely common perennial plants that predominantly grow in small vacant lots from urban areas to mountainous fields. However, Artemisia wormwood is an introduced species.

Morphologically, the underside of the leaves is cottony and fluffy, and the flower heads (inflorescences characteristic of the Asteraceae family) are usually oriented downwards (rarely upwards) and composed of tubular florets.

The most distinctive feature is that while most plants in the Asteraceae family are insect-pollinated, attracting insects with bright colors for pollination, Artemisia species have tubular florets that are wind-pollinated, relying on the wind to carry their pollen.

One theory suggests that this characteristic evolved when the ancestors of the Artemisia genus, which are closely related to the Chrysanthemum genus, moved into arid regions with fewer insects and switched to wind-pollinated flowers.

In fact, this aligns with the fact that Artemisia species can adapt and grow even in dry, concrete-filled areas.

Mugwort and its relatives have a long history of being used for food and medicine. Although they can be found everywhere these days, it seems that their use has decreased. However, I think most Japanese people have eaten mugwort mochi, which is made from mugwort. In Okinawa, mugwort is called "fuuchiba" and, despite its distinctive taste, is commonly eaten.

In addition, Artemisia princeps is also edible, but distinguishing between these plants is often very difficult in the wild, partly because their flowers are inconspicuous and their characteristics are hard to see.

What are the differences between mugwort, wormwood (Artemisia princeps), bitter wormwood, and male wormwood?

There are approximately 30 species of Artemisia in Japan alone, making it quite difficult to distinguish between them.

However, for reference purposes, we will only consider methods of distinguishing between four species here. Among these four species, *Artemisia princeps* and *Artemisia rupestris* can be clearly distinguished by carefully observing their leaves (Kanagawa Prefecture Flora Survey Association, 2018).

First, while mugwort, wormwood, and bitter wormwood have pinnately compound leaves, meaning the leaves are finely lobed like bird feathers, in contrast to muscovado, where the central leaves have shallower lobes and are usually spatulate-wedge shaped. There is a great deal of variation in the leaves, so you will need to examine several leaves, but it should be relatively easy to identify.

Furthermore, while white hairs are prominent on the leaves of Artemisia princeps, Artemisia japonica, and Artemisia glabra, there are almost no white hairs on Artemisia japonica.

Another important taxonomic difference is that while Artemisia princeps, Artemisia japonica, and Artemisia glabra produce both female and hermaphroditic flowers, Artemisia rupestris produces only female flowers and not hermaphroditic flowers. However, confirming this is limited to the flowering season and would be difficult for the average person.

Regarding the remaining three species, the differences are that in Artemisia princeps and Artemisia japonica, white hairs grow only on the underside, the pinnately compound leaves are not very finely divided, and the tips of the compound leaves are relatively sharp, while in Artemisia rupestris, white hairs grow on the upper surface as well, the pinnately compound leaves are more finely divided, and the tips of the compound leaves are relatively rounded.

Therefore, you can clearly see that wormwood is whitish in appearance.

The two species mentioned above are overwhelmingly rarer than mugwort, and the dominant species growing in towns is usually mugwort.

Artemisia japonica is more resistant to salt and drought damage than Artemisia sulphureus and can be found growing on coastlines (Iriyama, 2006).

What is the difference between mugwort and yomogi (Erigeron annuus)?

The most difficult to grow are mugwort and aster.

The only difference between Artemisia princeps and Artemisia japonica, according to field guides, is that Artemisia princeps has flower heads that are 1.2–1.8 mm in diameter, while Artemisia japonica has flower heads that are 1.8–2.5 mm in diameter. In other words, the parts that look like flowers (which are actually clusters of flowers) are larger in Artemisia princeps.

Therefore, it may be almost impossible to distinguish them outside of their flowering season.

While *Erigeron annuus* is sometimes described as a variety with wider leaf lobes, which could potentially help distinguish it, there is no specific description of how wide the leaf lobes must be to identify *Erigeron annuus*.

From a distribution standpoint, it seems that we can currently confirm that the plants found east of the Kanto region in Honshu are Artemisia princeps, while those found in Okinawa are Artemisia nipponica.

However, there is a clear difference in taste; Western mugwort is less bitter and has a softer texture, making it more suitable for eating.

While distinction is important from a culinary standpoint, mugwort and wormwood are broadly considered varieties within the species Artemisia indica. In some countries and eras, classifications treat mugwort, wormwood, and Artemisia japonica as a single species, indicating that they are an extremely closely related group (Shimono, 2014).

Are there any other similar species?

As mentioned above, there are many varieties, but if you carefully examine the shape of the leaves, you'll find that there are surprisingly few similar species. Nevertheless, you might still find it quite difficult.

Artemisia montana resembles mugwort and magnolia, but unlike them, it has almost no pseudostipules at the base of the petiole, and its flower heads are bulbous and bell-shaped. "Pseudostipules" are leaf-like structures that extend to the left and right from the base of the petiole on the plant body. This is relatively easy to identify, but the flower heads are frankly too ambiguous. It is common in Hokkaido and is usually found in high-altitude mountainous areas on Honshu, so those found in lowlands are likely to be large-sized mugwort.

Artemisia japonica var. lacinifolia resembles Artemisia japonica, but unlike Artemisia japonica, its leaves are pinnately deeply lobed, and the lobes are linear-lanceolate.

Gray wormwood (Artemisia sieversiana) resembles bitter wormwood, but unlike bitter wormwood, its leaf lobes gradually narrow and have sharp tips.

Artemisia vulgaris resembles mugwort and asterias, but is not currently listed in Japanese botanical guides. However, overseas studies have indicated its distribution in Japan, and its actual distribution is still not well understood (Shimono, 2014).

What are the differences in how to use mugwort, wormwood (Artemisia princeps), bitter wormwood, and male wormwood?

What are some uses for mugwort?

Mugwort has a distinctive aroma, and the young shoots picked in spring can be boiled and used in dishes such as blanched greens, soups, or even in kusa mochi (mugwort rice cakes) or deep-fried (Odachi & Hiyama, 2013). It can also be used to make mugwort tea.

Kusa mochi (known as yomogi mochi in the Kansai region) is said to have originated in the Heian period as a rice cake kneaded with cudweed, one of the seven spring herbs, but by the Edo period, the use of mugwort became established (Yamashita, 2019).

Moxibustion, or "kyu," uses moxa, which is an important part of the traditional East Asian medicine practice. Moxa is made from dried mugwort leaves with the downy hairs on the underside (Oda, 1984; Odachi & Hiyama, 2013). In this practice, moxa is burned on selected areas of the body surface (skin) to provide thermal stimulation, which is used for disease prevention and treatment. However, Artemisia montana (Japanese wormwood) is also used in some cases. Furthermore, since the plant distributed in China is not mugwort but Korean wormwood (Artemisia argyi), it is highly likely that this is used in countries other than China.

It has many medicinal uses, and its leaves are used as a crude drug called "gaiyo," which has hemostatic properties. Some of the gaiyo is actually mugwort, which is called Korean mugwort in China.

Young shoots and budding plants, after being dried and brewed into a tea, are traditionally used as a folk remedy for stomach ailments, abdominal pain, diarrhea, anemia, and cold sensitivity. More mature plants are also dried and added to bathwater as a bath additive to relieve lower back pain and hemorrhoids.

Mugwort is known to be highly nutritious, particularly rich in minerals and vitamins. Among vegetables, it ranks third in potassium content (after Swiss chard and parsley), second in iron content (after parsley), and eighth in beta-carotene content (Ando et al., 2022). Furthermore, mugwort is known to have strong antioxidant properties due to its high content of vitamins and polyphenols.

Its unique components include cineole, thujone, β-caryophyllene, borneol, and camphor (Odachi & Hiyama, 2013).

How can I use Artemisia princeps?

Although *Artemisia princeps* has a different distribution than *Artemisia japonica*, and is therefore used in different regions, its uses are very similar to those of *Artemisia princeps*.

In the Western Himalayas, it is called "thitepati" and is used by indigenous people to treat indigestion, chronic fever, and other liver diseases (Koul et al., 2017). In Nepal, the juice of this plant is used to treat dysentery, abdominal pain, and diarrhea. The young leaves are cooked and eaten with barley, adding color and flavor to rice.

For food, the Garo people (a tribe living in the Noklek Biosphere Reserve in Meghalaya, India) eat the tender sprouts as a vegetable.

Nepalis use the juice of the leaves to treat skin diseases, and the dried leaves and flowers are used as an insect repellent.

In Okinawa, it is called Fuchiba, and in the Ryukyuan language, it means "ba (leaf) that cures Fuchi (wind: illness)," which translates to "wind leaf" in Japanese. It has been widely used in households as a medicinal herb because it is believed to be effective in reducing fever, gastrointestinal diseases, and gynecological diseases (Japan Society for Food Science and Technology, 2021).

In cooking, it is often used in dishes such as Fuchiba Jushi (rice cooked with mugwort) and Boroboro Jushi (rice porridge with mugwort) (Watanabe, 2008; Japan Society for Food Science and Technology, 2021). Jushi refers to rice porridge. Its use varies by region.

In addition, it is sometimes added raw to Okinawa soba, and when used in hijaa-jiru (goat soup), it serves to mask the odor.

The reason why Artemisia japonica can be readily eaten raw may be because its leaves are more fragrant than those of Artemisia sylvestris (Yamashita, 2019) and easier to eat.

Chemically, it contains volatile oils such as β-thujone, hernialin, 1,8-cineole, estragole, savinyl acetate, ciscrisanthenyl acetate, dabanone oil, and terpineol, and possesses antifungal properties (Koul et al., 2017). Two novel compounds, trans-ethyl cinnamate and piperitone, have been isolated by chromatographic distillation.

How can wormwood (Artemisia princeps) and mugwort (Artemisia rupestris) be used?

Wormwood is an introduced species and therefore has no traditional uses in Japan, but it has a history of being used in Europe and Turkey for medicinal purposes similar to mugwort (Koul et al., 2017). It is too bitter to eat raw and is used in the herbal liqueur "absinthe."

Scientifically, its antiparasitic, antibacterial, antioxidant, and hepatoprotective properties have been proven, and experimentally, wormwood essential oil has shown antibacterial activity against budding yeast and Candida albicans.

Although Artemisia princeps is not widely used in Japan, the same subspecies found overseas has been widely used in folk medicine to treat eczema and fever.

How is pollination done?

Artemisia plants typically produce large conical inflorescences at the tips of their stems, bearing numerous small flower heads that hang downwards. The flower head is a structure unique to the Asteraceae family; it is not a single flower, but rather an inflorescence (a cluster of flowers). It consists of countless tiny flowers (florets) that may possess stamens and pistils.

There are two types of florets: ray florets and disc florets. However, in mugwort, only disc florets are present, and within these disc florets, the inner part of the flower head contains bisexual flowers (with both stamens and pistils), while the outer part contains female flowers (with only pistils).

As mentioned above, it is unusual for a member of the Asteraceae family to be wind-pollinated (Shimono, 2014; Yamashita, 2019). However, insect-pollinated varieties were also confirmed in 2022 (Hussain et al., 2024).

Regarding pollen, while animal-pollinated pollen sometimes has spines on its surface, Artemisia pollen is smooth, which is thought to be advantageous when dispersed by wind (Bolick, 1990).

What are the seed dispersal methods?

The fruits of the Artemisia genus are obovate achenes, glabrous or hairy. They lack pappus or have very short hairs. The seeds are contained within the very small achenes, resulting in a very high yield.

Therefore, it is thought that there is no special method of seed dispersal, but because the fruit and the seeds inside are very small and the yield is very high, it is thought that, at least in the case of wormwood, it is easily dispersed by water and animals in addition to gravity (Goud et al., 2015).

References

Ando, Masaya; Ogata, Ayano; Kuronuma, Takanori; Matsumoto, Takeshi; and Watanabe, Hitoshi. (2022). Evaluation of domestically produced mugwort varieties for food use. Journal of the All Japan Acupuncture and Moxibustion Society, 72 (1), 68-78. https://doi.org/10.3777/jjsam.72.68

Bolick, MR (1990). The pollen surface in wind-pollination with emphasis on the Compositae. In M. Hesse, & F. Ehrendorfer (Eds.), Plant Systematics and Evolution Vol. 5: Morphology, Development, and Systematic Relevance of Pollen and Spores (pp. 39-51). Springer. https://doi.org/10.1007/978-3-7091-9079-1_4

Goud, BJ, Dwarakanath, V. & Swamy, BC (2015). A review on history, controversy, traditional use, ethnobotany, phytochemistry and pharmacology of Artemisia absinthium Linn. International Journal of Advanced Research in Engineering and Applied Sciences, 4 (5), 77-107. https://indianjournals.com/article/ijareas-4-5-008

Hussain, M., Thakur, RK, Khazir, J., Ahmed, S., Khan, MI, Rahi, P., … & Mir, BA (2024). Traditional uses, phytochemistry, pharmacology, and toxicology of the genus Artemisia L.(Asteraceae): A high-value medicinal plant. Current Topics in Medicinal Chemistry, 24 (4), 301-342. https://doi.org/10.2174/1568026623666230914104141

Iriyama, Yoshihisa. (2006). Artemisia japonica. Journal of the Japanese Society of Landscape Architecture, 31 (4), 449. ISSN: 0916-7439, https://www.jsrt.jp/pdf/dokomade/31-4otokoyomogi.pdf

The Japanese Society for Food Science and Technology. (2021). Traditional Japanese Home Cooking: Donburi, Zosui, and Okowa. Agricultural, Forestry and Fisheries Culture Association. ISBN: 9784540191824

Kanagawa Prefecture Flora Survey Association. (2018). Kanagawa Prefecture Flora 2018 Electronic Edition. Kanagawa Prefecture Flora Survey Association. ISBN: 9784991053726,https://flora-kanagawa2.sakura.ne.jp/efloraofkanagawa.html

Koul, B., Taak, P., Kumar, A., Khatri, T., & Sanyal, I. (2017). The Artemisia genus: A review on traditional uses, phytochemical constituents, pharmacological properties and germplasm conservation. Journal of Glycomics & Lipidomics, 7 (1), 142. https://doi.org/10.4172/2153-0637.1000142

Odachi, Junko & Hiyama, Keiichiro. (2013). On the effects and uses of mugwort (Artemisia princeps). Tezukayama University Faculty of Contemporary Life Studies Bulletin, 9, 1-9. ISSN: 1349-7073, https://tezukayama.repo.nii.ac.jp/records/777

Oda, Ryuzo. (1984). Research on moxa (I): Recent manufacturing processes and the raw material, mugwort. Journal of the All Japan Acupuncture and Moxibustion Society, 33 (4), 427-430. https://doi.org/10.3777/jjsam.33.427

Shimono, Yoshiko. (2014). Artemisia indica Willd. var. maximowiczii (Nakai) H. Hara: From the perspective of a greening plant. Grass and Greenery, 6, 23-31. https://doi.org/10.24463/iuws.6.0_23

Yamashita, Tomomichi. (2019). Mugwort in Everyday Life. Nature Conservation, 568, 18-19. ISSN: 0386-4138, https://www.nacsj.or.jp/magazine/14752/

Watanabe, Yoshio. (2008). Dictionary of Okinawan Folklore. Yoshikawa Kobunkan. ISBN: 9784642014489

Akebia, Akebia trifoliata, Akebia quinata, and Stauntonia hexaphylla all belong to the Akebia family. They are climbing plants with palmately compound leaves, and a key characteristic is that male and female flowers bloom separately. Akebia and Akebia trifoliata are particularly famous for the edible white, gelatinous pulp inside their fruits. While they are associated with nostalgic rural flavors from childhood memories, few people may be able to distinguish between them. They can basically be distinguished by the shape of their leaves, and differences also appear in the shape of their flowers and the degree to which their fruits dehisce. Cross-pollination by insects is essential for their flowers, and it is known that the size difference between male and female flowers is a strategic feature. Seed dispersal is also interesting, as they rely on a variety of animals, including mammals, birds, and ants. This article will explain the classification, morphology, and ecology of the Akebia family.

What are Akebia, Mitsuba Akebia, Goyou Akebia, and Mube?

Akebia quinata, also known as Akebia quinata, is a deciduous climbing woody plant commonly found in the forest edges of hills and mountains, distributed across Honshu, Shikoku, and Kyushu in Japan; the Korean Peninsula; and China. Its Japanese name is said to derive from the fact that its fruit splits open.

Akebia trifoliata subsp. trifoliata, also known as three-leaved akebia, is a deciduous climbing woody plant commonly found in Hokkaido, Honshu, Shikoku, and Kyushu in Japan, as well as in China, growing at the edges of forests in hilly and mountainous areas.

Akebia x pentaphylla, also known as five-leaved akebia, is a natural hybrid of Akebia quinata and Akebia trifoliata, and is a deciduous climbing woody plant that is rarely found in areas where Akebia quinata and Akebia trifoliata grow together.

Stauntonia hexaphylla, also known as Tokiwaakebi, is a deciduous climbing woody plant distributed in Honshu (south of the Kanto region), Shikoku, Kyushu, and the Ryukyu Islands in Japan; the Korean Peninsula; and China. It grows in forest edges and is often planted as a hedge in parks and private homes. Makino suggests that the origin of the Japanese name comes from the fact that its fruit was offered to the imperial court, hence the name Ohonihe (大供) became Ohomube (苞苴), and then Mube (Kato and Nakamura, 1971). However, the basis for this argument is unclear.

All of these plants belong to the Akebia family, are climbing plants, have palmately compound leaves, and are monoecious, but a key characteristic is that their flowers are unisexual, meaning that male flowers grow separately.

[Seed Plant Encyclopedia #121] What are the species of the Akebia family? Photo list

The Lardizabalaceae family consists mainly of climbing woody plants, with shrubs being rare. The leaves are trifoliate or palmately compound with five leaflets. The flowers are unisexual, monoecious, and borne in racemes, radially symmetrical and trimeral. The sepals are petal-like. The fruit is an ellipsoidal berry with a fleshy pericarp. (Eastern Asia…)

ecological-information.com

Of the four species, three, excluding Stauntonia hexaphylla, belong to the genus Akebia. Their most distinctive feature is that when ripe, their fruit splits open, exposing a liquid, fleshy interior.

This fruit is unique, and its name varies depending on the source. Although it is a "follicle (a fruit consisting of one carpel that dehisces along the internal or external suture)" (Shimizu, 2001), it is sometimes called a "berry" because its interior is a liquid that animals can eat (Mogi et al., 2000). Since 3 to 5 fruits can sometimes be clustered together, in this case it is called an "aggregate fruit," and is sometimes referred to as an "aggregate follicle" or "aggregate berry."

In Japan, there has been a long-standing tradition of eating this fruit, and it is associated with people's memories of the taste of the countryside from their childhood. There are also cultivated varieties of Akebia trifoliata, which are sometimes sold commercially.

However, several closely related species are known, and all of them are edible, so perhaps few people can correctly distinguish between them.

In particular, Akebia trifoliata has compound leaves with five leaflets, but Akebia quinata also has five leaflets, which can be confusing. Some companies even sell Akebia quinata as "Akebia trifoliata with five leaflets."

What are the differences between Akebia, Mitsuba Akebia, Goyou Akebia, and Mube?

As a fundamental point, Akebia quinata, Akebia trifoliata, and Akebia quinata belong to the Akebia genus, while Stauntonia hexaphylla belongs to the Stauntonia genus (Kanagawa Prefecture Flora Survey Association, 2018).

Therefore, there is a significant difference in form.

In Akebia, Akebia trifoliata, and Akebia quinata, the leaves are deciduous, the sepals are three cup-shaped, the stamens are six and free, and the fruit dehisces, whereas in Stauntonia hexaphylla, it is evergreen, the sepals are six in number (three outer ones are lanceolate and three inner ones are linear), the stamens are six and fused, and the fruit does not dehisce.

While there are many factors to consider, the biggest difference is whether the plant is deciduous or evergreen. In other words, Akebia, Akebia trifoliata, and Akebia quinata lose their leaves in winter, resulting in soft, thin, light green leaves, while Stauntonia hexaphylla retains its leaves even in winter, giving it sturdy, hard, dark green leaves. This can be observed by examining the leaves.

Another easily noticeable difference, even just looking at the leaves, is that in Stauntonia hexaphylla, the veins are prominent on both the upper and lower surfaces of the leaves, and the number of leaflets can range from three in young trees to five to seven in mature trees. These features are entirely unique to Stauntonia hexaphylla and are not found in the Akebia genus.

It's easy to mistakenly think that Akebia plants have multiple leaves, but these are palmate compound leaves, meaning that what was originally a single leaf has divided into 3 to 7 leaflets. These divided parts that look like a single leaf are called "leaflets."

Another point to note is that while botanical guides state that the fruit of Stauntonia hexaphylla does not split open, actual photographs show that it does split open slightly, though not as much as in the Akebia genus.

Of the remaining three species, Akebia trifoliata is a hybrid of Akebia quinata and Akebia quinata, and therefore exhibits intermediate characteristics (Kanagawa Prefecture Flora Survey Association, 2018; Yoshizawa and Arase, 2024; Hayashi, 2025).

Focusing on the number of leaflets, Akebia and Akebia trifoliata usually have five leaflets, while Akebia quinata has only three. This difference is reflected in its Japanese name.

However, since Akebia quinata can occasionally have 3 to 4 leaflets, you need to check for multiple leaflets.

If we focus on the serrations of the leaflets, we can see that while Akebia trifoliata and Akebia quinata usually have serrations, Akebia quinata does not.

However, this is also Akebia quinata, and some of the current year's branches in the upper layers lack serrations, so it is necessary to check multiple leaves.

Focusing on the flowers, in Akebia quinata, the male flowers are sparsely arranged and the sepals are pale purple, while the female flowers have long stalks and protrude from the male inflorescence. In contrast, in Akebia trifoliata and Akebia quinata, the male flowers are densely arranged and the sepals are dark reddish-purple, while the female flowers have somewhat shorter stalks and do not protrude from the male inflorescence.

Based on the above, I believe you can definitely distinguish between the four types.

What are the differences in how Akebia, Mitsuba Akebia, Goyou Akebia, and Mube are used?

The main use of Akebia and Mitsuba Akebia is, of course, for their sweet fruit. The fruit ripens in the autumn (around September to October).

In addition to consuming the wild fruit, there are also cultivated varieties of Akebia trifoliata for fruit production (Matsumoto et al, 2022; Yoshizawa & Arase, 2024).

The fruit consists of a pericarp and a white pulp (placenta) that encloses the black seeds, and this pulp is edible (Fruit Tree Horticulture Laboratory, Faculty of Agriculture, Yamagata University, 2020).

The typical way to eat it is to pick the fruit, eat the white gelatinous substance (placenta) as is, taste the flesh, and then spit out the seeds inside.

In rural areas, it has long been a popular snack for children playing in the mountains, and it is sometimes described as a "rare fruit that evokes nostalgia," adding color to fond childhood memories (Yoshizawa & Arase, 2024).

The fruit is sweet and juicy, and rich in nutrients such as sugars, proteins, amino acids, vitamins, and minerals (Huang et al., 2022).

Grapes are highly regarded nutritionally, containing a high amount of various vitamins such as beta-carotene, vitamin B, and vitamin C (108-930 mg/100 g), which is higher than apples, grapes, and bananas. They are also rich in minerals such as potassium (3.2-4.9 mg/g), magnesium (1.00-1.51 mg/g), and calcium (0.47-0.49 mg/g), as well as amino acids, including all eight essential amino acids.

The peel became a topic of discussion when YouTuber Hikakin, not knowing how to eat it, discarded the flesh and ate the peel raw, describing it as bitter and unpleasant (J-CAST News Entertainment Team, 2025). However, it is not edible raw.

However, the peel can also be eaten after being boiled or stir-fried, and dishes such as "stir-fried akebi peel with miso" are known (Fruit Tree Horticulture Laboratory, Faculty of Agriculture, Yamagata University, 2020).

The young shoots can be used in dishes such as blanched greens, salads, soups, and stir-fries (Takahashi, 2003). In the Tohoku region, the young shoots of Akebia trifoliata are called "kinome" (tree buds) because they contain less bitterness than Akebia quinata, and were used in "kinome-meshi" (tree bud rice).

In addition to being cultivated for ornamental purposes in horticulture (Huang et al., 2022), the outer bark of the thick vine stems is removed and sun-dried, and this is called "Mokutsu," which has been used as a herbal medicine effective against nephritis, urethritis, and cystitis due to its diuretic, anti-inflammatory, analgesic, cardiac stimulant, antibacterial, and antioxidant properties (Maciąg et al., 2021).

Akebia quinata does not produce fruit, so it is not used for food.

While the fruit of the Stauntonia hexaphylla is edible, it is small and does not split open completely, making it difficult to eat, and therefore it is rarely found in the market.

However, Makino suggests that the origin of the Japanese name is that the fruit was offered to the imperial court, and that this was called "Ōhonihe" (大供), which became "Ōmube" (苞苴), and then "Mube" (Kato and Nakamura, 1971). There is also a theory that when Emperor Tenji was presented with it, he replied, "Mube naru kana" (meaning "That is indeed true"). The veracity of these claims is quite questionable, but it seems certain that Mube was used in ancient times (Wano, 2015).

How did pollination work? Was it to deceive insects with large female flowers?!

The shape of the flowers differs greatly between the Akebia and Stauntonia genera (Kanagawa Prefecture Flora Survey Association, 2018).

In the Akebia genus, the flowering period is in spring, from April to May. Male flowers are numerous and borne at the tip of the inflorescence, with short filaments that curve inward in an arching shape, forming a spherical cluster. Female flowers are larger than male flowers, borne in small numbers at the base of the inflorescence, and have 3 to 9 oblong carpels that spread outwards. What appear to be three petals are actually modified sepals.

It has a strong scent and is sometimes called "the flower with the fragrance of chocolate" in Europe and America.

What kinds of insects visit this flower? Akebia species are self-compatible and cannot produce fruit without pollen from other individuals.

Studies on Akebia have shown that the main pollinating insects are small, solitary wasps (non-caste wasps) such as Lasioglossum sp., hoverflies Epistrophe balteata (Syrphidae), and Japanese honeybees Apis cerana japonica (Apidae) (Kawagoe & Suzuki, 2002).

While there is insufficient research on Akebia trifoliata, some believe it may be similar to Akebia quinata (Matsumoto et al, 2022). However, there are morphological differences, such as the male flowers of Akebia trifoliata being darker in color, so it has not been verified whether they are truly the same.

While the Japanese akebia (Akebia quinata) produces flowers, it does not produce fruit, so it cannot reproduce.

By the way, there's a curious difference between the male and female flowers of the Akebia genus. The female flowers are noticeably larger and more conspicuous than the male flowers. Why is this?

This is thought to be "intersexual mimicry," where female flowers mimic male flowers (Kawagoe & Suzuki, 2002; 2003). In other words, since female flowers have no stamens, they naturally have no pollen and offer no reward to pollinators, but they grow larger than male flowers to appear more attractive to pollinators in order to deceive insects into thinking "there's food here!"

Furthermore, especially in solitary bees, they will visit the more attractive-looking female flowers before moving on to the male flowers. This prevents self-pollination within the same individual by preventing pollen from the male flowers from touching the stigma of the female flowers, thus promoting cross-pollination.

As mentioned above, Akebia is self-incompatible, so this cross-pollination is thought to be for the purpose of avoiding reproductive interference (by its own pollen), rather than suppressing inbreeding (preventing inbreeding depression) (Kawagoe & Suzuki, 2005).

Surprisingly, however, hoverflies can distinguish between male and female flowers and only visit the male flowers, resulting in a situation where they steal nectar.

On the other hand, Stauntonia hexaphylla flowers in spring, from April to May, producing short racemes from the leaf axils. These inflorescences have 6 sepals and bear 3 to 7 pale yellow flowers that face downwards and have a single reddish-purple stripe on the inside (Mogi et al., 2000). There are no significant differences between male and female flowers except for the stamens and pistils.

Despite having the exact same flowering period, the reason why the male and female Stauntonia hexaphylla are identical in appearance remains unknown, unfortunately due to insufficient research on pollinating insects.

The facts above confirm that wild insects (mainly bees) produce delicious akebi fruit, both wild and cultivated. This kind of benefit is called an "ecosystem service," so if you want to eat delicious akebi, please take an interest not only in the akebi itself, but also in the natural environment that supports these insects.

How did they disperse their seeds? They used all sorts of methods: mammals, birds, ants, you name it!?

As mentioned above, the fruits of the Akebia family ripen in the autumn and are "follicles" that split open or crack, but are also called "berries" because the inside is a liquid that animals can eat.

The thick rind changes from green to red to purple as it ripens, and when it splits open, the inside is exposed, revealing black seeds encased in a white, gelatinous placenta.

Fruits that are clearly large and would be considered tasty for humans are likely to be dispersed by animal means, particularly by mammals.

In fact, the fruit of Akebia has been used by martens and raccoons (Takatsuki, 2017; 2018), and there are records of the fruit of Akebia trifoliata being used by martens, raccoons, and Japanese macaques (Takatsuki, 2017; Kumagai and Saito, 2022; Otani, 2005).

The fruits of the Stauntonia hexaphylla are also used by martens and raccoons (Takatsuki, 2017; 2019).

The slimy seed coat is thought to be adapted to slip through the teeth of animals (Okamoto, 1999).

However, there are also records of an increase in seedlings of Akebia quinata and Akebia trifoliata within goldenrod communities (Karasawa, 1978). This suggests that birds may be contributing to seed dispersal of Akebia quinata and Akebia trifoliata.

Generally, red fruits are only visible to birds and monkeys with well-developed color vision, so considering this point, it is plausible that seeds are dispersed by both mammals and birds.

Furthermore, the seeds of Akebia and Akebia trifoliata have elaiosomes. This indicates that these are parts that ants eat, and that after being eaten by animals, the seeds are excreted in their feces and then dispersed again by ants, thus contributing to ant dispersal (Nakanishi, 1988).

In the field, there have been observations of brown ants gathering around the seeds (Kusui & Kusui, 1999). In experiments where seeds were placed directly near ant nests, black garden ants and brown ants carried them away (Fujii et al., 2012).

However, unlike Akebia quinata and Akebia trifoliata, Stauntonia hexaphylla does not have elaiosomes (Kusui & Kusui, 1999).

References

Huang, P., Zang, F., Li, C., Lin, F., Zang, D., Li, B., & Zheng, Y. (2022). The Akebia genus as a novel forest crop: A review of its genetic resources, nutritional components, biosynthesis, and biological studies. Frontiers in Plant Science, 13, 936571. https://doi.org/10.3389/fpls.2022.936571

Fujii, Mari; Kosaka, Ayumi; and Masui, Keiji. (2012). Plants that rely on ants to disperse their seeds. Kyosei no Hiroba, 7, 63-68. ISSN: 1881-2147, https://www.hitohaku.jp/publication/book/kyousei7_063.pdf

J-Cast News Editorial Department, Entertainment Team. (February 6, 2025). Hikakin, who caused a controversy 8 and a half years ago, immediately apologizes... and looks back on it with laughter: "Why did I have to apologize...?" He reveals his true feelings. J-Cast News. https://www.j-cast.com/2025/02/06501301.html

Karasawa, Koichi. (1978). A study on the diet and seed dispersal of fruit-eating birds in urban areas. Birds, 27 (1), 1-20. https://doi.org/10.3838/jjo1915.27.1

Kanagawa Prefecture Flora Survey Association. (2018). Kanagawa Prefecture Flora 2018 Electronic Edition. Kanagawa Prefecture Flora Survey Association. ISBN: 9784991053726

Kato, Kaname & Nakamura, Tsuneo. (1971). Yama-kei Color Guide: Flowering Trees 1. Yama-kei Publishers.

Kawagoe, T., & Suzuki, N. (2002). Floral sexual dimorphism and flower choice by pollinators in a nectarless monoecious vine Akebia quinata (Lardizabalaceae). Ecological Research, 17 (3), 295-303. https://doi.org/10.1046/j.1440-1703.2002.00489.x

Kawagoe, T., & Suzuki, N. (2003). Flower-size dimorphism avoids geitonogamous pollination in a nectarless monoecious plant Akebia quinata. International Journal of Plant Sciences, 164 (6), 893-897. https://doi.org/10.1086/378659

Kawagoe, T., & Suzuki, N. (2005). Self-pollen on a stigma interferes with outcrossed seed production in a self-incompatible monoecious plant, Akebia quinata (Lardizabalaceae). Functional Ecology, 19 (1), 49-54. https://doi.org/10.1111/j.0269-8463.2005.00950.x

Hayashi, Masayuki. (2025). Tree Leaves, 3rd Edition: Identifying 1390 Species Through Real-Life Scans. Yama-kei Publishers. ISBN: 9784635070447

Kumagai, Minami and Saito, Masayuki. (2022). Seasonal changes in the diet of raccoons in temperate forests of the Shonai region of Yamagata Prefecture. Journal of the Tohoku Forest Science Society, 27 (1), 1-10. https://doi.org/10.18982/tjfs.27.1_1

Kusui, Haruo & Kusui, Yoko. (1999). Tree seeds of temperate forests carried by martens. In Keisuke Ueda (Ed.), Seed Dispersal: The Evolution of Mutual Aid Vol. 2: Forests Created by Animals (pp. 37-50). Tsukiji Shokan. ISBN: 9784806711933

Nakanishi, Hiroki. (1988). Ant-dispersed plants distributed in the warm temperate zone of Japan. Journal of the Ecological Society of Japan, 38 (2), 169-176. https://doi.org/10.18960/seitai.38.2_169

Maciąg, D., Dobrowolska, E., Sharafan, M., Ekiert, H., Tomczyk, M., & Szopa, A. (2021). Akebia quinata and Akebia trifoliata: a review of phytochemical composition, ethnopharmacological approaches and biological studies. Journal of Ethnopharmacology, 280, 114486. https://doi.org/10.1016/j.jep.2021.114486

Matsumoto, D., Shimizu, S., Shimazaki, A., Ito, K., & Taira, S. (2022). Effects of self-pollen contamination in artificial pollination on fruit set of 'Fuji Murasaki' Akebia trifoliata. The Horticulture Journal, 91 (4), 431-436. https://doi.org/10.2503/hortj.UTD-385

Mogi, Toru; Ota, Kazuo; Katsuyama, Teruo; Takahashi, Hideo; Shirokawa, Shiro; Yoshiyama, Hiroshi; Ishii, Hidemi; Sakio, Hitoshi; and Nakagawa, Shigetoshi. (2000). Flowers Blooming on Trees: Polypetalous Flowers (Vol. 2, 2nd edition). Yama-kei Publishers. 719pp. ISBN: 9784635070041

Okamoto, Motoharu. (1999). The mutually beneficial relationship between birds and succulents. In Keisuke Ueda (Ed.), Seed Dispersal: The Evolution of Mutual Aid Vol. 1: Seeds Carried by Birds (pp. 27-39). Tsukiji Shokan. ISBN: 9784806711926

Otani, T. (2005). Characteristics of medium-sized mammals as seed dispersers of berries—mainly using Japanese macaques as an example. Nagoya University Journal of Forest Science, 24, 7-43. https://doi.org/10.18999/nagufs.24.7

Shimizu, Takemi. (2001). Illustrated Dictionary of Botanical Terms. Yasaka Shobo. ISBN: 9784896944792

Takahashi, Hideo. (2003). Wild Edible Plants of Japan. Gakken Plus. ISBN: 9784054018815

Takatsuki, Shigeki. (2017). Characteristics of fruits used by martens—a review. Mammalian Science, 57 (2), 337-347. https://doi.org/10.11238/mammalianscience.57.337

Takatsuki, Shigeki. (2018). Characteristics of fruits used by raccoons—a review. Mammalian Science, 58 (2), 237-246. https://doi.org/10.11238/mammalianscience.58.237

Wano, Yasuhiro. (2015, November 16). The "Akebia" Fruit of Immortality: People from all over Japan constantly seek this legendary fruit that has been offered to the Imperial Family since ancient times... Sankei News. https://www.sankei.com/article/20151116-R4UEWT34HRNKDMX4RQHNCLPSM4/

Yamagata University, Faculty of Agriculture, Department of Fruit Tree Horticulture. (2020). The Story of Yamagata's Akebi. Sugihado Printing. ISBN: 9784991178504, https://ssl.samidare.jp/~lavo/zaisakuken/box/akebi.pdf

Yoshizawa, Yuri & Arase, Teruo. (2024). Taxonomic study of three Akebia species based on morphological variation of leaves. Shinshu University Faculty of Agriculture AFC Reports, 22, 45-54. ISSN: 2433-8877, http://hdl.handle.net/10091/0002002080

European pumpkins, Japanese pumpkins, and pepo pumpkins are all annual vining plants belonging to the Cucurbitaceae family, Cucurbita genus. Originally from the Americas, they are very popular in Japan, playing an important role in both everyday meals and Halloween celebrations. However, the three species are often confused, and no websites clearly explain their differences. They can be distinguished by their leaves, flowers, and fruit stalks. To briefly summarize the differences in use, focusing solely on Japan: European pumpkins are currently the most common, with sweet, sticky fruit used in stews and salads. Japanese pumpkins were the dominant variety before World War II, characterized by their mild flavor, and were used in stews, but were eventually replaced by European pumpkins. However, Japanese pumpkins are still used for sweets. Pepo pumpkins were very minor, although varieties like the Kinshiuri exist, but after the war, they became more common with zucchini and Connecticut field pumpkins used for Halloween jack-o'-lanterns. Pumpkins are not native to Japan or the West; they originated in the Americas. Surprisingly, the Japanese pumpkin is the most common in the West. It is believed that the fruit was originally eaten and the seeds dispersed by large mammals like the now-extinct mastodon. This article will explain the classification, morphology, history, and culture of the genus Cucurbita.

What are European pumpkins, Japanese pumpkins, and pepo pumpkins?

The European pumpkin (Cucurbita maxima), also known as the Japanese pumpkin, is a climbing annual plant native to South America (Argentina and Bolivia) and cultivated worldwide for its edible fruit (RBG Kew, 2026).

Japanese pumpkin (Cucurbita moschata), also known as Oriental pumpkin or Boubra, is a climbing annual plant native to Central America (Belize, Guatemala, and Mexico) and cultivated worldwide for its edible fruit. Among the vast number of varieties, some of the most representative Japanese varieties include the crane-necked pumpkin (Tsurukubi Kabocha) var. luffiformis, whose fruit is long and slender with a neck resembling a crane's neck; the chrysanthemum-seat pumpkin (Kikuza Kabocha) var. meloniformis, whose fruit has deep vertical grooves and whose cross-section resembles a chrysanthemum flower; and the gourd-shaped Saikyo pumpkin (Tounasu/Shishigatani Kabocha) var. meloniformis 'Toonas'.

Cucurbita pepo, also known as pepo pumpkin, is a climbing annual plant native to Central America (Mexico) and cultivated worldwide for its edible and ornamental fruits. It boasts a vast number of varieties, including the edible zucchini subsp. pepo 'Melopepo', the horticultural variety and subspecies of the Connecticut field pumpkin subsp. pepo 'Connecticut field', which has oblate-spherical fruits used in jack-o'-lanterns, and the ornamental pumpkin subsp. texana (var. ovifera is a synonym), which has oddly shaped fruits (Gong et al., 2012).

Both are annual vines belonging to the Cucurbitaceae family, genus Cucurbita. They are creeping plants, and their most distinctive feature is their large, fleshy fruit, as well as their yellow, bell-shaped corollas, which are important characteristics from a taxonomic standpoint.

However, the incorrect naming conventions of "Japanese pumpkin" and "Western pumpkin," which do not reflect their origins, have led to the misconception that Japanese pumpkins are a native species and Western pumpkins came from the West.

This is based on the historical circumstances of how both species were introduced to Japan, but in reality, as mentioned above, they are native to the Americas and are neither Japanese nor Western in any way.

Moreover, despite the fact that European pumpkins, Japanese pumpkins, and pepo pumpkins are completely different species, they are treated as if they were separate varieties, and few websites point out specific morphological differences, further exacerbating the misunderstanding.

The pepo pumpkin is relatively obscure and not well-known. However, edible zucchini is a cultivated variety of pepo pumpkin, and the Connecticut Field Pumpkin, a cultivated variety of pepo pumpkin, is used for Halloween jack-o'-lanterns.

Because there are many cultivated varieties of these three types of pumpkins, the names "○○ pumpkin" are often used without explanation, leading to confusion.

What are the differences between European pumpkins, Japanese pumpkins, and pepo pumpkins?

Let's start by clarifying the biological and morphological differences between the three main types. While there are many varieties, biologically speaking, the three most common types are sufficient, and understanding just these three is all you need.

As a fundamental point, as mentioned above, their natural distribution differs: the European pumpkin is native to South America (Argentina and Bolivia), the Japanese pumpkin is native to Central America (Belize, Guatemala, and Mexico), and the pepo pumpkin is native to Central America (Mexico).

While it's undeniable that the three species evolved from a common ancestor, the fact that the European pumpkin is distributed primarily in South America suggests that the three species have completely separated without interbreeding in the wild.

We will consider the specific differences in form (Wu et al., 2011).

In Japanese pumpkins, the flower sepals are linear with leaf-like tips, and the fruit stalk expands significantly at the tip. In contrast, in European pumpkins and pepo pumpkins, the flower sepals are linear to linear-lanceolate with slender tips, and the fruit stalk does not expand significantly at the tip.

The description "the flower's sepals are linear with leaf-like tips" is a little difficult to understand, but it means that the sepals at the back of the flower extend slightly to the sides, increasing their surface area and making them somewhat similar in shape to ordinary leaves. In pumpkins and pepo pumpkins, the sepals are simple and slender.

The phrase "the stalk expands significantly at the tip" is also difficult to understand, but essentially, Japanese pumpkins have a circular, whitish indentation at the tip of the stalk where the fruit's stem ends, while European pumpkins and pepo pumpkins lack this, resulting in a flat, simple appearance. This is one reason why Japanese pumpkins look "bumpy." However, some varieties, such as the vine-necked pumpkin, have evolved in a way that makes this characteristic less noticeable.

Regarding pumpkins (Pumpkin serrulata) and pepo pumpkins (Pumpkin pepo), the differences are that in pumpkins, the leaf blades are kidney-shaped to spherical with nearly entire margins, the sepals are lanceolate, and the fruit pedicels lack angular grooves and do not thicken at the tip, while in pepo pumpkins, the leaf blades are triangular to ovate-triangular with 5 to 7 irregular lobes, the sepals are linear-lanceolate, and the fruit pedicels have angular grooves and are slightly thickened at the tip.

For this, looking at the shape of the leaves should be sufficient. You can understand it as simply this: European pumpkins have leaves that don't separate, while pepo pumpkins have leaves that do.

The fruit morphology is so diverse that it's not a reliable indicator for distinguishing between the three varieties. However, you can differentiate them if you remember the shape of each variety, and nowadays, you can easily identify the variety name using Google Image Search.

Other pumpkin varieties cultivated in Japan include Cucurbita ficifolia and Cucurbita argyrosperma, but these are less common in Japan, so we will omit them.

What's the difference between pumpkin and squash?

In English, pumpkins are sometimes referred to as "pumkin" or "squash."

However, this does not distinguish the three species biologically; "pumpkin" is a general term for varieties of pumpkins in the Cucurbita genus that have orange rinds, while "squash" is a general term for varieties of pumpkins in the Cucurbita genus that have green rinds.

Therefore, the most common variety of pumpkin in Japan is called squash. It's all a bit confusing, isn't it?

What are the differences in history and uses between European pumpkins, Japanese pumpkins, and pepo pumpkins?

The uses of European pumpkins, Japanese pumpkins, and pepo pumpkins vary considerably from country to country. Therefore, it's difficult to summarize them in a single sentence.

To summarize briefly, focusing solely on Japan, the European pumpkin is currently the most common, with sweet and sticky fruit used in stews and sweets. The Japanese pumpkin was the most common before World War II, characterized by its mild flavor, and was used in stews, but it was replaced by the European pumpkin. The Pepo pumpkin was very minor, although there are varieties like the Golden Melon, but after the war, it became common with zucchini and the Connecticut Field Pumpkin, also known as Jack-o'-lantern.

In Japan, the most common type of pumpkin is the European pumpkin, while in Europe, the most common is the Japanese pumpkin.

Each of the three varieties has undergone significant changes in form due to micro-evolution and selective breeding brought about by Native Americans through domestication (Bisognin, 2002; Spengler, 2020). Just like corn and tomatoes, the efforts of Native Americans are what have enriched our current diets.

It is highly valued for its enormous seeds and fruits, which are edible, but they weren't always that large.

First, it is thought that selection for larger seeds led to the development of larger fruits. Generally, bitter fruits contained non-bitter seeds, so it is thought that the seeds were the first to be used as food. Subsequently, immature fruits were selected for their non-bitter flesh, and mature fruits were selected for their non-bitter, starchy flesh and non-woody peel.

What are the uses of European pumpkins?

As mentioned above, the European pumpkin originates from South America and for a long time was not used by any people other than Native Americans. It began to spread to North America and the rest of the world after the "Columbian Exchange" following the arrival of Columbus (1492-) (Nee, 1990). Records show that various varieties were used by Native Americans in the 16th century. In Japan, two to three varieties were introduced from the United States in 1863, and many more varieties were introduced by the Hokkaido Development Commission in the early Meiji period, becoming established in various regions (Fujita, 2010).

Therefore, although it is called "Western pumpkin," it has no connection to the West in terms of its place of origin. This is a name unique to Japan, as it was introduced from the United States.

Moreover, European pumpkins require very high temperatures to grow and are not well-established in Northern Europe , the British Isles, or regions with short or cool summers (Boswell, 1949). Therefore, as will be explained later, Japanese pumpkins are used in European pumpkin pies! This fact is the source of much confusion.

The primary use of the European pumpkin is for its edible fruit. Compared to the Japanese pumpkin, the European pumpkin is characterized by its sticky texture (Izumi, 2006).

It is eaten in tropical America, Japan, and parts of the United States (Boswell, 1949), as well as in Africa, India, Bangladesh, and Myanmar (Ferriol & Nuez, 2004). It is particularly popular in Japan, where it is used almost interchangeably with the Japanese pumpkin (Nihonkabocha), which will be discussed later. It is used in dishes such as simmered pumpkin, pumpkin soup, pumpkin tempura, and thinly sliced pumpkin in salads. Ironically, in the West, the Japanese pumpkin is preferred as food, as will be discussed later.

Rich in nutrients, regardless of variety, it is an excellent source of highly beneficial dietary fiber and minerals such as potassium, calcium, phosphorus, magnesium, sulfur, silicon, iron, and zinc to supplement your diet (Czech et al., 2018).

Furthermore, according to records for varieties within Japan, a comparison of β-carotene equivalents per 100 g of edible portion shows that while the pepo pumpkin (Kinshiuri) contains 49 μg and the Japanese pumpkin contains 730 μg, the Western pumpkin contains 4000 μg, which is approximately 5.6 times more (Fujita, 2010).

Furthermore, while the vitamin C content of pepo pumpkin (Kinshiuri) is 11 μg and that of Japanese pumpkin is 16 μg, that of European pumpkin is approximately three times higher at 43 μg, exceeding the vitamin C content of large tomatoes.

Pumpkin seeds are also used for food and, when roasted, are rich in protein, fat, and vitamin B1.

What are the uses of Japanese pumpkins?

Japanese pumpkins, being native to Central America, were long used by Native Americans and were an important food plant, ranking second only to corn and beans in many parts of the American economy before the colonial era (Boswell, 1949). The flowers, seeds, and flesh were all edible.

However, unlike the European pumpkin, it was cultivated and used early on in North America by Native Americans, along with the pepo pumpkin. On the other hand, it never reached South America.

It was after the arrival of Columbus (1492-) and the "Columbian Exchange" that it began to spread throughout the world via Europe.

Japanese pumpkins can withstand drought and frost during their flowering season, and although they are tropical plants, they are more cold-hardy than European pumpkins, making them the most popular pumpkin variety in Europe. European pumpkin pies use Japanese pumpkins. They are also consumed in many countries, including the United States, Mexico, India, China, and Brazil (Men et al., 2021).

Japanese pumpkins arrived in Japan before European pumpkins. It is believed that the introduction of Japanese pumpkins began in 1542 when a Portuguese ship drifted ashore in Bungo Province, and in 1549, they presented Japanese pumpkins to Otomo Sorin, who applied for permission to trade (Nishi, 1980; Fujita, 2010).

Otomo Sorin was a samurai and daimyo of Bungo Province (present-day Oita Prefecture) from the Sengoku period to the Azuchi-Momoyama period. He is known for actively adopting Christianity and Western culture by conducting trade with the Nanban (Southern Barbarians) from Kyushu, which he ruled as a Christian daimyo.

It is well known that the word "kabocha" (pumpkin) originates from "Cambodia," and it is said that the pumpkins introduced by Portuguese ships at that time were produced in the country of Cambodia (post-Angkor Cambodia) (Aoba, 2000).

It is believed that the pumpkin arrived in Nagasaki in 1573, and its cultivation began to spread widely among farmers, gradually spreading throughout Japan. Varieties such as the Tsurukubi pumpkin, Kikuza pumpkin, and Shishigatani pumpkin originated from this indigenous variety. Other varieties include the Kurokawa pumpkin (Hyuga pumpkin) and the Kogiku pumpkin.

It seems that the Japanese pumpkin (Nihonkabocha) was named as such because it was introduced to Japan before the European pumpkin (European pumpkin) and many indigenous varieties developed and diversified. However, considering that it did not originally exist in Japan and has become a minor vegetable in Japan today, it can be said that the name is misleading.

During and after World War II in the Pacific, Japanese pumpkins were an important food source. While today we imagine simmered pumpkin dishes made with sweet Western pumpkins, back then, they were made with Japanese pumpkins and had a much milder flavor.

Although the aforementioned varieties remain as traditional vegetables, they may seem quite minor in Japan. However, considering that Japanese pumpkins are used in pumpkin puree, even though many are imported from overseas, and that they are frequently used as an ingredient in commercially available pumpkin pie mixes and in sweets and desserts sold around Halloween, they continue to be a part of our diet in various forms.

The current primary use of Japanese pumpkins is for their fruit. Compared to Western pumpkins, Japanese pumpkins are characterized by their milder flavor. This may be related to the fact that the carbohydrate content in the flesh of Japanese pumpkins is high at 78.641 TP3T, significantly higher than that of Western pumpkins (69.511 TP3T) (Men et al., 2021).

In addition to carbohydrates, dietary fiber (such as pectin), vitamins A, C, and E, it is also rich in minerals (such as manganese, magnesium, and potassium).

In Japan, as mentioned above, pumpkins are considered to have less nutritional value than European pumpkins and are therefore poorly regarded (Fujita, 2010). However, overseas, their nutritional content has been studied in detail and they are attracting attention (Men et al., 2021). This may be due to differences between Japanese and European varieties.

What are the uses of pumpkins?

The pepo pumpkin, also native to Central America (Mexico), was used by Native Americans, with the oldest known records dating back 8,000 to 10,000 years ago in Oaxaca, southern Mexico, and approximately 7,000 years ago in Ocampo, Tamaulipas, Mexico (Nee, 1990). Along with the Japanese pumpkin, it held a position second only to corn and beans in many parts of the pre-colonial American economy (Boswell, 1949). The flowers, seeds, and flesh were all edible.

It was after the arrival of Columbus (1492-) and the "Columbian Exchange" that the pepo pumpkin began to spread throughout North America and the rest of the world. There is a record of a variety of pepo pumpkin being described in Germany in 1552.

A vast number of varieties have been developed for edible and ornamental purposes (Gong et al., 2012), and it has become particularly popular in Italy, where the zucchini variety was created in the late 19th century. Unlike other pumpkins, it is harvested in the summer, and in Europe and America, it is considered a type of summer squash. Because the unripe fruit and flowers of zucchini, which are high in water content, are eaten, few people may realize that it is a type of pumpkin. Ratatouille, a French dish, is a representative dish that uses zucchini.

Also, the Jack-o'-lanterns used for Halloween are not made from European pumpkins, but from a variety of pepo pumpkin called Connecticut Field Pumpkin. The ornamental pumpkin, a subspecies of pepo pumpkin, is purely for decoration and does not taste good.

Halloween originated from the Samhain harvest festival of the Celts, which later incorporated Christian elements. Jack-o'-lanterns were made to ward off evil spirits by acting as substitutes, but originally sugar beets or turnips were used. Pumpkins began to be used around the time Celtic immigrants moved to the United States. The story of Jack is a fictional tale.

Pepo pumpkins were first introduced to Japan after the First Sino-Japanese War (1894-1895), with varieties from North China being brought in, but they did not become very popular (Nishi, 1980). The Kinshiuri variety, whose flesh separates into thin, thread-like strands, is likely from this period.

Rather, zucchini and Connecticut field pumpkins arrived in Japan after World War II as part of Western culture, through a completely different route, and became established without being recognized as pepo pumpkins (Izumi, 2006). Zucchini was first imported from the United States around the late 1970s (early 1970s) when Italian cuisine became popular (Nogyo Sangyo Bunka Kyokai, 2004).

While the primary use is for the edible fruit, zucchini is unique in that its flowers are also eaten (known as "flower zucchini"), and some varieties, such as Connecticut Field Pumpkins and Ornamental Pumpkins, are purely ornamental and not tasty to eat.

How are pumpkin seeds dispersed? Were pumpkin fruits eaten by extinct animals?!

Pumpkin fruits are nutritious and a savior for humans, but there is one big question (Kistler et al., 2015).

In the natural world, what animals eat the fruit and then disperse the seeds through their feces?

At first glance, you might think that wild animals could eat pumpkins once they're ripe, but even when ripe, pumpkins are covered in a hard rind and are inedible to most animals.

Furthermore, it is known that the fruit pulp produces cucurbitacin, a triterpenoid compound that is cytotoxic and has a strong bitter taste, thus repelling small mammals.

Moreover, even if they are eaten, unless the animal swallows the seeds whole, they won't end up in its feces, preventing the species from expanding its habitat. The worst-case scenario is when animals, like rats, only eat the seeds.

In fact, recent research suggests that pumpkins are not the ancestors of currently existing animals, but rather were eaten and dispersed by large mammals (megafauna) that lived on the American continent before the Holocene epoch.

In fact, intact pumpkin seeds have been found in the dung deposits of mastodons (primitive elephant-like creatures). It certainly seems that mastodons could easily eat the fruit by stepping on it.

All of these large mammals were driven to extinction by Native Americans after the Holocene epoch, but now Native Americans are acting as seed dispersers by cultivating them (Spengler, 2020).

This phenomenon, where the current environment and adaptations are out of sync, is called "ecological anachronism," and it is believed that the same phenomenon occurs in avocados, cacao, American mulberry, American honey locust, and sachalinensis.

References

Aoba, Takashi. 2000. Selected Works of Takashi Aoba, Vol. 1: Japanese Vegetables. Yasaka Shobo, Tokyo. 311pp. ISBN: 9784896944563

Boswell, VR 1949. Our Vegetable Travelers. The National Geographic Magazine 96(2): 145-216. ISSN: 0027-9358, https://www.plantanswers.com/publications/vegetabletravelers/index.html

Bisognin, DA 2002. Origin and evolution of cultivated cucurbits. Ciência Rural 32: 715-723. https://doi.org/10.1590/S0103-84782002000400028

Czech, A., Stępniowska, A., Wiącek, D., Sujak, A., & Grela, ER 2018. The content of selected nutrients and minerals in some cultivars of Cucurbita maxima. British Food Journal 120(10): 2261-2269. https://doi.org/10.1108/BFJ-10-2017-0599

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Gong, L., Paris, HS, Nee, MH, Stift, G., Pachner, M., Vollmann, J., & Lelley, T. 2012. Genetic relationships and evolution in Cucurbita pepo (pumpkin, squash, gourd) as revealed by simple sequence repeat polymorphisms. Theoretical and Applied Genetics 124(5): 875-891. https://doi.org/10.1007/s00122-011-1752-z

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I originally have a science background, but I enjoy reading world history content.

I've heard something that caught my attention. It's the theory that spices (spices excluding the stems, leaves, and flowers) don't have much antibacterial property, and that "spices were used to mask the smell of rotten meat." I've always been skeptical about whether this is true.

Our investigation has concluded that this theory is highly unfounded. The reason is that spices are too expensive for ordinary people to use.

The medicinal properties of spices themselves are diverse, including antibacterial, antioxidant, appetite-stimulating, and anti-inflammatory effects. However, the reason why wealthy people in Europe and America sought out spices from abroad during the Age of Discovery was likely for their exotic flavors and because they stimulated the secretion of addictive neurotransmitters (brain hormones) in the brain.

Ultimately, this develops into conspicuous consumption among the wealthy in Europe and America (consumption to flaunt wealth).

However, it is becoming clear that some spices can actually be used to mask the characteristic fishy smell, so they are not spoiled, but it is true that some spices can be used to eliminate fishy odors.

Another theory suggests that the antibacterial and antioxidant properties of spices, which enhance their preservation, were important. This is an explanation that you sometimes see in high school world history classes.

While it is true that spices have antibacterial properties, it is unlikely that there was a demand for them in Europe and America during the Age of Discovery. On the other hand, antibacterial properties were likely important in their places of origin.

This article will explain why the idea that spices were used to mask the smell of rotten meat is false, and the real reason why European countries sought spices during the Age of Discovery.

What are the differences between Japanese pepper (Zanthoxylum piperitum), Chinese pepper (Zanthoxylum sibiricum), and Japanese pepper (Zanthoxylum ailanthoides)? We'll explain how to distinguish between similar species! What are their uses? What insects visit the flowers? Birds apparently love the seeds because they don't find them spicy!?

Japanese pepper (Zanthoxylum piperitum), Japanese sansho, and Japanese sansho are common species in Japan, and Japanese pepper in particular remains an essential ingredient in cooking today. All belong to the genus Zanthoxylum in the Rutaceae family, and are very similar in that they have many thorns all over the plant and odd-pinnately compound leaves consisting of an odd number of leaflets. Japanese pepper has a distinctive aroma...

ecological-information.com

What's the difference between dill (yin-dill) and fennel (foeniculum vulgare)? An explanation of how to distinguish between similar species.

Dill and fennel both belong to the Apiaceae family, share a strong aroma throughout the plant, and are used both as herbs (leaves) and spices (fruits). Their leaves, in particular, are known as "fish herbs" and pair exceptionally well with fish dishes. Furthermore, they are also similar in morphology...

ecological-information.com

Why can we say that the theory that spices were used to mask the smell of rotten meat during the Age of Discovery is false?

Why is the claim that "spices were used to mask the smell of rotten meat" considered to have little basis in fact?

The biggest problem is that spices from the Age of Discovery were too expensive (Murphy, 2024).

Europe already had an abundance of native herbs used in cooking, such as sage, rosemary, and thyme, as well as strongly flavored vegetables like leeks and onions. However, "spices" (such as pepper, nutmeg, and cloves) could only be imported through the spice trade from the Middle East and Asia.

Exotic spices, popularized by returning Crusaders and pilgrims, were already in vogue as highly prized luxuries among the upper classes in the Middle Ages, even before the Age of Discovery. However, their relative rarity, prestige, and the long distances it took to reach tables in France and England made them extremely expensive. They were simply unaffordable for ordinary households.

Furthermore, most households could quickly slaughter and eat animals by raising livestock or fish, hunting, or commissioning these activities. Examples of livestock included geese, ducks, chickens, pigs, and sheep.

In addition, if you have any leftovers, there are preservation methods such as salting, smoking, drying, and honey-preserving. Jerky and ham are examples of this.

From the above, it can be concluded that medieval Europeans did not deliberately eat rotten meat.

However, it has been confirmed that essential oils extracted from the fruit (fennel seeds) of fennel (a type of spice native to the Mediterranean coast) and the kernels of nutmeg seeds (native to Southeast Asia) can actually eliminate the odor of meat and fish (Takahashi et al., 2004).

Therefore, while it remains possible that native European plants like fennel were used to remove animal or fishy odors, it's unlikely to be the smell of rotting meat.

Why did the misinformation spread?

Why did this claim circulate? An influential book is involved (Myers, 2006).

In 1939, J.C. Drummond and Anne Wilbraham published "The Englishman's Food: Five Centuries of English Diet," in which they suggested that the wealthy in medieval Europe (and cunning bakers and grocery shop owners) desperately needed spices, primarily because meat was starting to spoil and the spices masked the smell and flavor of stale ingredients.

However, Drummond was a biochemist, not an expert in medieval food culture. Furthermore, he assumed from the outset that medieval preservation techniques were rudimentary and that "the main purpose of spices was to mask flavors." His work lacked documentary evidence and relied heavily on misinterpretations and speculation.

However, the readability of his writing, combined with the authority he gained from his social standing, gave his books weight and made them an ideal reference for anyone wanting to casually research the history of food.

This theory, like a rumor spreading, created a chain of mentions where inaccurate information was repeated as if it were the truth.

Worst of all, the speaker heard the same inaccurate information from multiple sources, but failed to realize that it all stemmed from a single source, creating the misconception that this theory was the dominant one.

What was the real reason Europe sought spices from abroad during the Age of Discovery?

So what was the reason for seeking spices during the Age of Discovery (mid-15th to mid-17th centuries)?

The primary reason is probably that it's a "delicacy" and has an exotic taste.

This might seem a bit simplistic, but the tendency for wealthy people to become gourmets in search of new flavors and seek out rare ingredients is still observed today.

If it were simply delicious, that would be the end of it, but for example, although it is native to Central and South America, the capsaicin contained in the fruit of the chili pepper is known to stimulate the secretion of beta-endorphins and dopamine, which are types of neurotransmitters (brain hormones) in the brain and are also called brain narcotics, due to its spiciness (pain) (Fattori et al., 2016).

This can have an effect that, while not pathological, could be described as addiction.

Other examples of spices affecting brain hormones, although primarily based on animal studies, include the following:

These effects likely contributed to a stronger craving for spices (Le Couteur & Burreson, 2003=2011).

As trade further developed and spices became even more expensive, the use of spices evolved into a way for the wealthy in Europe and America to flaunt their wealth and demonstrate that they could afford to use expensive spices on a daily basis (Freedman, 2005).

This corresponds to what is called "constancy consumption" in economics. This is not merely "showing off," but has been theorized in evolutionary biology as "handicap theory," and is known as an important motivation for consumption in humans (Miller, 2009=2017).

As described above, the reasons for seeking spices during the Age of Discovery likely evolved from the pursuit of delicacies to addiction and then to conspicuous consumption.

The reason Europe went to the trouble of obtaining spices by sea was that in the 15th century, the Ottoman Empire destroyed the Byzantine Empire and expanded into the Eastern Mediterranean, imposing extremely high tariffs. As a result, the supply of spices that had originally come in through the Eastern trade (Levant trade) between Islamic Qalimi merchants and Italian merchants in Venice was cut off.

As a result, the Portuguese and Spanish efforts to find spices unaffected by the Islamic world spread to the imperialist powers of the Netherlands, Britain, France, Germany, America, Italy, and Belgium, leading to colonial rule by Western powers around the world.

Is the antibacterial properties of spices related to the demand for spices?

However, and this is a bit complicated, while the reasons why Europeans and Americans sought spices during the Age of Discovery can be attributed to the pursuit of delicacies, their addictive nature, and their conspicuous consumption, the reasons why the indigenous people of those colonies used spices are likely different.

For the local people, unlike Westerners, spices grew naturally, were inexpensive, and were deeply integrated into their customs and food culture.

While taste and addictive properties are certainly contributing factors, the reasons for its long-term integration into the culture likely include its lipid-derived antioxidant, antibacterial, insecticidal, and animal-repellent properties, as well as its appetite-stimulating, anti-inflammatory, and odor-masking effects (Gottardi et al., 2016). Furthermore, although scientific proof is still lacking, it was also expected to play a role as a herbal medicine for specific organs.

In particular, antioxidant and antibacterial properties are thought to have been important for improving the preservation of food and for embalming corpses. Antibacterial properties have been proven in 99 major spices, including pepper, chili peppers, cloves, nutmeg, and sansho pepper.

Such antibacterial effects may not have been particularly valued in the European and American countries during the Age of Discovery.

However, as Dutch-Asian trade progressed from the 17th to the 18th centuries, and as a result of the expansion of trade and competition among merchants and companies, the prices of many commodities began to converge between regions. Colonial goods such as spices, tea, and sugar also spread to the general households in Europe and America (De Zwart, 2016), and became commonly consumed by ordinary households.

In Japan, after the Meiji Restoration (1853), spices originating from South America, such as chili peppers, were added to the existing Asian spices.

At this stage, some people may have started to become aware of its antibacterial properties and health benefits.

Since then, scientific research has advanced, proving that it actually has functions such as antibacterial properties and health benefits, and it has once again attracted attention.

Thus, the role of spices has changed in complex ways depending on the region and era. While the theory that spices were consumed for their odor-masking or antibacterial properties during the "Age of Discovery" is rather weak, it's important to note that spices themselves do have those effects.

References

Chauhan, S., Tiwari, A., Verma, A., Padhan, PK, Verma, S., & Gupta, PC 2024. Exploring the potential of saffron as a therapeutic agent in depression treatment: a comparative review. The Yale Journal of Biology and Medicine 97(3): 365-381. https://doi.org/10.59249/XURF4540

De Zwart, P. 2016. Globalization in the early modern era: new evidence from the Dutch-Asiatic trade, c. 1600–1800. The Journal of Economic History 76(2): 520-558. https://doi.org/10.1017/S0022050716000553

Fattori, V., Hohmann, MS, Rossaneis, AC, Pinho-Ribeiro, FA, & Verri Jr, WA 2016. Capsaicin: current understanding of its mechanisms and therapy of pain and other pre-clinical and clinical uses. Molecules 21(7): 844. https://doi.org/10.3390/molecules21070844

Freedman, P. 2005. Spices and late-medieval European ideas of scarcity and value. Speculum 80(4): 1209-1227. https://doi.org/10.1017/S0038713400001391, https://gebeasley.org/famished/wp-content/uploads/2015/10/document-2-1.pdf

Garabadu, D., Shah, A., Ahmad, A., Joshi, VB, Saxena, B., Palit, G., & Krishnamurthy, S. 2011. Eugenol as an anti-stress agent: modulation of hypothalamic-pituitary-adrenal axis and brain monoaminergic systems in a rat model of stress. Stress 14(2): 145-155. https://doi.org/10.3109/10253890.2010.521602

Gottardi, D., Bukvicki, D., Prasad, S., & Tyagi, AK 2016. Beneficial effects of spices in food preservation and safety. Frontiers in Microbiology 7: 186557. https://doi.org/10.3389/fmicb.2016.01394

Hidayat, R., Wulandari, P., & Reagan, M. 2022. The potential of cinnamon extract (Cinnamomum burmanii) as anti-insomnia medication through hypothalamus pituitary adrenal axis improvement in rats. Acta Medica Academica 51(2): 79-84. https://doi.org/10.5644/ama2006-124.375

Kim, CY, Seo, Y., Lee, C., Park, GH, & Jang, JH 2018. Neuroprotective effect and molecular mechanism of [6]-Gingerol against scopolamine-induced amnesia in C57BL/6 mice. Evidence-Based Complementary and Alternative Medicine 2018(1): 8941564. https://doi.org/10.1155/2018/8941564

Kulkarni, SK, & Dhir, A. 2010. An overview of curcumin in neurological disorders. Indian Journal of Pharmaceutical Sciences 72(2): 149-154. https://doi.org/10.4103/0250-474X.65012

Le Couteur, PC, & Burreson, J. 2003. Napoleon's buttons: How 17 molecules changed history. Tarcher, 384pp. ISBN: 9781585422203 [=2011. Spices, explosives, pharmaceuticals—17 chemical substances that changed world history. Chuokoron-Shinsha, Tokyo. 368pp. ISBN: 9784120043079]

Li, S., Wang, C., Li, W., Koike, K., Nikaido, T., & Wang, MW 2007. Antidepressant-like effects of piperine and its derivative, antiepilepsirine. Journal of Asian Natural Products Research 9(5): 421-430. https://doi.org/10.1080/10286020500384302

Miller, G. 2009. Spent: Sex, Evolution, and Consumer Behavior. Viking Adult, 384pp. ISBN: 9780670020621 [=2017. Consumer Capitalism! The Evolutionary Psychology of Show-offs. Keisou Shobo, 480pp. ISBN: 9784326299256]

Murphy, D. 2024, October 29. Did Medieval Kings Need Spice to Cover Up Rotten Food?. Youth in Food Systems. https://seeds.ca/schoolfoodgardens/13837-2/

Myers, D. 2006. Drummond's Rotten Meat: When Good Sources Go Bad. Medieval Cookery. https://www.medievalcookery.com/notes/drummond.pdf

Seneme, EF, Dos Santos, DC, Silva, EMR, Franco, YEM, & Longato, GB 2021. Pharmacological and therapeutic potential of myristicin: A literature review. Molecules 26(19): 5914. https://doi.org/10.3390/molecules26195914

Takahashi, YK, Nagayama, S., & Mori, K. 2004. Detection and masking of spoiled food smells by odor maps in the olfactory bulb. Journal of Neuroscience 24(40): 8690-8694. https://doi.org/10.1523/JNEUROSCI.2510-04.2004

Xu, J., Xu, H., Liu, Y., He, H., & Li, G. 2015. Vanillin-induced amelioration of depression-like behaviors in rats by modulating monoamine neurotransmitters in the brain. Psychiatry Research 225(3): 509-514. https://doi.org/10.1016/j.psychres.2014.11.056

In short, Adlerian psychology can be described as "a psychology that fosters the ability to live in cooperation with others (community feeling) by choosing one's own life (self-determination), acting in accordance with one's purpose (teleology), and letting go of unnecessary control over others (separation of tasks)."

However, his psychology is buried among many self-help books, and many people may find it somewhat dubious. In fact, even in later generations, his ideas tend to be forgotten and are not quoted even when he says the same things.

Indeed, Adler's ideas are based more on a synthesization of his own clinical experience than on a series of scientific verifications. Furthermore, they address not only facts but also themes beyond the realm of science, such as "how should one live?", and thus have aspects that are closer to philosophy. In that sense, some argue that it is not science.

This article will examine the extent to which Adlerian fundamental factual concepts are accepted in evolutionary biology, psychology, behavioral economics, neuroscience, and brain science. It is based on Miller & Dillman (2016), with additional papers added. Citations of papers mentioned in Miller & Dillman (2016) will be omitted.

In conclusion, the general direction is the same, but there are some differences in our views on conflict and free will.

About Adler and Adlerian psychology

Alfred Adler was a psychologist born in 1870 and died in 1937. The mainstream of psychology during his time was based on the idea that "human behavior is determined by past causes (such as childhood experiences, traumas, and physiological factors)."

For example, Freud emphasized "unconscious desires" and "sexual impulses" as causes. Psychiatry, too, followed a style of "recording symptoms and classifying cause and effect," essentially relying on "accumulating facts." As Adler interacted with patients as a physician, he began to have serious doubts about this "causal explanationism." This is what is called "causal theory."

Adler began to question this. In his youth, he started as an ophthalmologist and internist, treating many patients with lung diseases and tuberculosis. One day, he noticed that even with the same disease, the degree of recovery varied greatly from patient to patient. "Why is it that only those with a 'will to live' recover, even though they have the same disease?" The realization that this could not be explained by mere "physical differences" became Adler's first turning point. In other words, the idea began to take root in him that "people are not passive beings, but rather choose their own way of life." This is what is called "teleology."

After becoming a psychiatrist, Adler developed this idea, applying it to emotions and behavior as well. He parted ways with Freud and founded what is now known as Adlerian psychology, or "individual psychology."

Adlerian psychology is remarkably progressive in that it emphasizes one's own life and individuality, while advocating for exploring connections with society by utilizing one's abilities. I believe it is a very important field of psychology and philosophy, alongside the early Buddhism of Gautama Siddhartha (Buddha/Shakyamuni) in northern India in the 6th century BC, and the Stoic philosophy that began with Zeno in ancient Greece in the early 3rd century BC and spread throughout ancient Greece and Rome, as it helps to let go of the Western notion of pursuing only individual happiness and the extreme Japanese notion of "the nail that sticks out gets hammered down."

Is there any scientific basis for the concept of "community feeling"?

One of the core beliefs in Adlerian psychology is the idea that individuals have an innate capacity for social concern.

In Adlerian psychology, this is called "social interest," and it represents the feeling of being a part of society—whether family, community, or workplace—and the desire to connect with others and contribute. This can range from a family-centered perspective to a global one.

In short, Adlerian psychology argues that this lack of a sense of community—that is, the lack of the feeling that "I am contributing to communities on various scales"—is largely related to feelings of anxiety, unhappiness, isolation, inferiority complexes, and self-centered behavior.

Has research in neuroscience also shown that a sense of community is important?

This view aligns with many neurobiological perspectives on happiness, as stated in the textbook "A Counselor's Introduction to Neuroscience" (McHenry et al., 2014), and several studies suggest that expressing compassion and kindness may enhance relationships and mental and physical health (Fredrickson et al., 2013; Poulin & Holman, 2013).

Oxytocin is a hormone synthesized in the hypothalamus and secreted from the posterior pituitary gland. It is also known as the "love hormone" and is released when we feel social connection or when we care for someone.

Oxytocin is thought to be the source of feelings of happiness that come from having a sense of community, but it has also been found that the secretion of oxytocin does more than that; it also repairs physiological damage induced by stress.

A study by Poulin & Holman (2013) found that people who engaged in prosocial behavior had higher levels of endogenous oxytocin and fewer negative symptoms of stress. The authors suggest that prosocial behavior may be a way for people to stimulate the release of oxytocin and mitigate the negative effects of stress, demonstrating that oxytocin mitigates the adverse health effects of stress.

Another study by Fredrickson et al. (2013) reported that individuals who reported having a higher purpose, being connected to their community, and serving others had lower levels of inflammatory markers, while those who reported more hedonic experiences had elevated levels of pro-inflammatory genes and decreased levels of antiviral response.

Aristotle distinguished between "hedonia," which is happiness that pursues short-term pleasures such as enjoyment, satisfaction, and positive emotions, and "eudaimonia," which is happiness that comes from finding meaning and purpose in life and achieving long-term rather than short-term fulfillment. Here, however, it is interpreted that those who found eudaimonia in a social context were healthier.

These findings suggest, from a physiological and neurological perspective, that having a strong sense of community and contributing to the happiness of others has significant benefits for one's own mental stability and physical health.

Adler also referred to Darwin's theory of evolution, arguing that while other animals evolved physical strength, humans adapted to their environment by forming social groups, and that this is connected to the importance of having a sense of community (Adler & Iwai, 2024).

This idea is also proposed in the form of the social brain hypothesis from the perspective of current evolutionary biology, and can be said to be largely correct (Pedersen et al., 2014; Dunbar, 2024).

Is there any scientific basis for "Adlerian interpersonal relationships"?

Adlerian interpersonal relationships emphasize the separation of tasks (clearly defining one's own responsibilities and those of others, focusing on one's own tasks, and refraining from interfering with others' tasks until requested), rejecting "vertical relationships" (hierarchical relationships) and emphasizing "horizontal relationships" (equal relationships). Encouragement (giving people facing difficulties the energy to overcome them and the confidence that they can do it) is also recommended.

This is somewhat similar to "assertiveness" (self-assertion that respects oneself and others), which originated in behavioral therapy in modern times.

Assertiveness is a communication method and attitude that respects oneself and others, and expresses one's opinions, requests, and feelings frankly, honestly, and on an equal footing. It is consistent with Adlerian interpersonal relationships in that it recommends direct language (a rejection of the "culture of unspoken understanding") and emphasizes equality.

While Adlerian interpersonal relationships themselves lack sufficient scientific validation, several studies have shown that assertiveness can reduce anxiety, stress, and depression (Cantero-Sánchez, 2021; ElBarazi et al., 2024).

Similar ideas are prominent in early Buddhism, Stoic philosophy, and early Christianity, emphasizing the importance of protecting oneself while also showing compassion and respect for others within the community (Bazzano, 2005; Goerger, 2017; Case, 2024).

Is there scientific evidence for the "uniqueness of early childhood experiences"?

Adlerian psychology considers early childhood experiences to be extremely important for the overall development of an individual's view of themselves, others, and the world (Adler, 1956).

Adler (1956) argued that while individuals are born with certain tendencies, the manifestation of specific traits and talents is caused by the community (the surrounding environment).

In other words, this can be rephrased as the idea that "childhood experiences are qualitatively more important than adult experiences and are deeply involved in establishing one's 'lifestyle'."

In Adlerian psychology, "lifestyle" refers to an individual's unique "unconscious blueprint" for living their life, which is a fusion of childhood experiences and the need for belonging. It consists of three elements: self-concept (I am...), worldview (the world is...), and self-ideal (I want to be...).

Therefore, counselors in the Adlerian psychology school try to understand a person's inner world by deeply examining their family structure, including cultural and familial values, expectations of gender roles, the nature of relationships within their birth family, and their psychological birth order.

What about from a neuroscience perspective?

Current brain development models suggest that early childhood experiences have a significant impact on an individual's awareness of themselves, others, and the world, and are thought to complement Adler's view on early childhood experiences (Andersen et al., 2008; McHenry et al., 2014; Perry, 2009; Siegel, 2012).

Brain development begins in the brainstem in the womb and progresses to the prefrontal cortex in early adulthood. Neurologists believe that the fundamental structures related to the brain's regulatory circuits, a key element in discussions of mental health, are primarily formed during the first five years of life (Andersen et al., 2008; Perry, 2009).

In this process, children often internalize the neural circuits of their closest caregivers during their early childhood. While individuals are born with certain genetic predispositions, environmental experiences significantly influence which genetic predispositions are expressed or suppressed through a process called "epigenetics" (Garrett, 2011; Siegel, 2012).

Epigenetics is a mechanism that controls gene function (expression) without changing the DNA base sequence itself. Beginners in biology or those who still hold onto outdated biological ideas tend to think that "behavior is rigidly determined by genes, although there are environmental constraints." However, current biology has proven that, through the action of epigenetics, "individuals have the potential to be either way, and specific genes can be expressed depending on the environment, leading to certain behaviors."

In other words, not only are directly inherited genes involved, but also the environment during childhood, which can influence genetic expression and have both positive and negative effects later in life.

For example, Fallon (2013) examined individuals who engaged in violent psychopathological behavior using brain scans. They found that the participants shared similar neural activity profiles and patterns, specifically "decreased brain function in certain parts of the frontal and temporal lobes, areas generally associated with self-control and empathy."

Up to this point, it could be said that the person has lost their sense of community due to a brain abnormality. In a sense, this is normal.

However, further investigation suggests that some individuals, due to poor upbringing environments, may exhibit neurological activity profiles similar to those of individuals with psychopathic tendencies, even without showing high levels of aggression or low levels of empathy.

In other words, as Adler hypothesized, this suggests the possibility that early childhood experiences influence genetic predispositions.

This is very close to the reality when you consider cases where children born in slums commit crimes or join gangs without realizing it, influenced by their parents and those around them, or cases where children of toxic parents become toxic parents themselves.

Furthermore, Adler's ideas closely align with another psychological concept, "attachment theory," to the point that it's almost a rephrasing of it.

Attachment theory, proposed by psychologist John Bowlby in his research from the 1960s to the 1970s, is a theory that states that the emotional bonds (attachment) that people form with others have a significant impact on their mental health and interpersonal relationships.

Attachment theory was groundbreaking in that it demonstrated that the mother-child relationship, as explained by Freud, is not established through the child learning that "she is the one who breastfed me (satisfaction of need)," but rather through an instinctive and innate mechanism by which the child seeks out their parent, similar to other monkeys.

However, this theory was completed not by directly referencing Adler's earlier work, but by drawing on clinical observations, comparative studies, and references to animal behavior.

Although this attachment theory is old, it is still widely accepted today, and many neuroscientists have shown that attachment is internalized as tacit memory, and that secure attachment is associated with neural structures that promote emotion regulation, fear regulation, harmony, insight, self-understanding, empathy, and morality (Schore & Schore, 2008; Siegel, 2012), while insecure attachment is associated with decreased emotional and social intelligence, executive function, and stress regulation (Perry, 2009).

As described above, Adler's ideas, which emphasized childhood experiences, are still supported today, albeit with some changes in terminology.

Are "teleology" and "the lies of life" correct?

Teleology, in contrast to causalism which states that "human behavior is determined by past causes (such as childhood experiences, trauma, or physiological factors)," is the idea that "people choose their actions and emotions in the present in order to achieve some purpose, and the past causes cited are merely conveniently brought into play to suit that purpose."

This is a point that is often misunderstood because it is only written to this extent in textbooks, but even so, Adler did not deny that genes and the past are the cause of the current situation (Adler and Iwai, 2024).

However, I'm saying that the choice of the cause is ultimately up to the individual.

We often hear people say, "I can't get married because I don't have money and I'm not good-looking," but considering the counterexample of many people around the world who are married despite not having money or good looks, it's clear that even if there is a tendency for this to be the sole cause, it's wrong to attribute it to that. Nevertheless, this kind of expression is often seen.

While abuse can be a cause of delinquency, some people who experience it go on to achieve great success without resorting to crime.

Adler argues that we can choose whether to move in a constructive or unconstructive direction. Adler called the act of not taking action by making plausible excuses a "life lie."

I believe the validity of teleology and the concept of lies in life, that is, the error of causal theory itself, can be easily proven by simply providing exceptions.

So why does the brain make excuses and tell "lies about life" when it should actually be taking action?

In modern terms, this can be seen as "self-deception" (a psychological process in which one deceives oneself to justify or ignore one's own conscience or the truth, even though one knows it) in order to resolve "cognitive dissonance" (psychological discomfort arising from the simultaneous existence of contradictory thoughts or actions in one's mind) in response to "procrastination" behavior caused by "anxiety."

While humans can certainly achieve happiness and survival by maintaining the status quo and avoiding harm or potential threats, maintaining the status quo can also lead to negative consequences (Yamamori et al., 2023).

For example, when going through a job interview, you need to weigh the benefit of getting a new job against the risk of failing or experiencing embarrassment during the interview. While turning down one interview may have little impact on your life, habitually avoiding all job interviews will clearly lead to problems in the long run.

Consistently avoiding long-term benefits for the sake of short-term risks is called "procrastination" in psychology and "present bias" in behavioral economics. As the total of the lost rewards that could have been obtained through diligent effort accumulates, it has an increasingly negative impact, ultimately leading to missing out on important things in life.

Evolutionary biology and behavioral economics have pointed out that this is because humans tend to underestimate future benefits of survival, which are uncertain in the course of evolution (time discounting), and overestimate the risks they may face in the present (Rogers, 1994; Tomono, 2006).

Furthermore, neuroscientifically speaking, mouse experiments have shown that this anxiety process involves excessive strengthening of the connections between the hippocampus/amygdala and the prefrontal cortex (excessive theta wave synchronization), leading to overactivity of interneurons such as VIP ⁺ neurons, PV ⁺ neurons, and SST ⁺ neurons (Mack et al, 2023).

In other words, evolutionarily, the control system of the prefrontal cortex is overly active, making one more susceptible to anxiety. This leads to overestimating current failures and risks (punishments) over future rewards (things one wants to do), causing procrastination. However, because one also understands the downsides, cognitive dissonance occurs, and to resolve this, one resorts to self-deception by telling "lies about life."

In ancient times, when uncertainty was high and death was imminent, this could be considered a highly adaptive evolutionary trait, as it encouraged cautious behavior and promoted the maintenance of the status quo. However, in modern times, where technology has advanced and the risks of action have decreased, it can no longer be considered adaptive (Rogers, 1994; Rasmussen & Dover, 2006; Villmoare et al., 2024).

Early Buddhism and Stoic philosophy also warn against overestimating risks due to "delusions" and "attachments" (Ding et al., 2023). The same is true for early Christianity.

Is there a right way to have courage?

Adler states that "courage" is necessary to overcome "life's lies."

In Adlerian psychology, "courage" refers to the very "vitality" and "motivation" to overcome difficulties and challenges and to take positive action when faced with them.

Adler didn't actually list methods for summoning courage, but based on his intent, the following methods can be considered:

1. Start with small actions
2. Reducing unnecessary anxiety by separating issues
3. Using feelings of inferiority as motivation for growth
4. Be mindful of contributing to others
5. Strengthening self-determination

Of these, the idea of "starting with small actions" is now called "Small Wins" and was rediscovered by Weick (1984).

Small wins are small, achievable successes accumulated day by day towards achieving a larger goal. Weick argues that by breaking down large, complex problems into "small, attainable parts" and accumulating small wins, momentum and support can be gained, making change more likely.

For example, if you're studying, it could be something like memorizing vocabulary for just 10 minutes a day.

This leads to a sense of self-efficacy through achievement, creating a positive cycle of hope, belief, optimism, and confidence, as well as providing feedback for better strategies through learning through practice (Termeer & Dewulf, 2019).

The importance of "just trying something, even if it's small, rather than thinking about a big plan" is still strongly supported today. Agile development, a software development methodology, is one example of this.

On the other hand, there is insufficient research to determine whether separating issues truly leads to anxiety reduction, but it intuitively seems correct.

The idea of separating tasks is almost identical to the concept expressed in Stoic philosophy (Delaney, 2023).

Are there any flaws in Adlerian psychology?

I think there are two main differences between Adlerian psychology and modern thinking.

Is it true that there is no conflict?

First, let's consider the concept of conflict. Adlerian psychology does not recognize conflict between consciousness and the unconscious. This is called holism.

This rejects the idea of "fighting against one's inner self," instead positing that internal conflict exists to achieve one's goals.

This interpretation is not very common in modern times; for example, in evolutionary psychology, the mind is often explained not as a unified entity but as being composed of separate parts (modules) divided according to their purpose. This is also recently referred to as domain specificity (Oda & Otsubo, 2023).

Another example is the "elephant and mahout" metaphor, proposed by Jonathan Haidt, a social psychologist famous for positive psychology (Haidt, 2006). The "elephant and mahout" metaphor is also used in the early Buddhist scripture , the Dhammapada.

"Elephant" refers to the part of the mind that is separate from consciousness and is involved in reactions to stimuli and the formation of motivations through pleasure and displeasure, while "elephant handler" refers to the part that deals with consciousness, language, and rational long-term judgment.

The idea is that the elephant's behavior is a result of the evolutionarily more primitive development of the medulla oblongata, cerebellum, midbrain, and diencephalon, and that these are the main players, while the elephant handler, represented by the cerebral cortex, plays a supporting role, only able to slightly control the direction. In reality, conflicts between different parts of the cerebral cortex are also possible.

However, this is a matter of interpretation. There is no doubt that the elephant and the mahout work together towards some direction (purpose), and I believe that taking a holistic view of life is beneficial in that it prevents unconstructive thinking such as "I suffered again today because of the elephant," and even if the mahout's role is small, it allows us to positively receive messages from different parts of the brain.

Does free will exist?

Next, Adlerian psychology is based on the premise that free will exists. Therefore, it believes that individuals can choose better, more constructive actions for themselves.

On the other hand, in modern times, the prevailing view is the absence of free will (determinism), which holds that all human psychology and behavior are determined by a combination of environmental and genetic factors.

While it might be possible to have a deep philosophical discussion about this, it seems that Adler wasn't interested in such philosophical debates, but rather in assuming the existence of free will and encouraging efforts to change the future.

In psychology, several studies have shown that experimentally giving participants anti-free will messages leads to increased cheating, increased aggression, decreased willingness to help, decreased readiness for exercise, and decreased self-control. While recent meta-analyses have suggested that this has a low impact (Genschow et al., 2023), it may be possible in limited situations.

Fundamentally, accurate prediction of the future is impossible because its initial conditions are unknown, and since it is undetermined, the fact that the future can be changed through learning remains unchanged even if free will does not exist.

Finally, it's important to note that Adler's arguments are about 100 years old, and therefore lack a comprehensive model of early childhood development, meaning they cannot fully explain all aspects of life by modern standards (Miller & Dillman, 2016).

References

Alfred Adler, translated by Toshinori Iwai. 2024. Adler's Words in a Superb Translation: Essential Edition. Discover Twenty-One, Tokyo. 229pp. ISBN: 9784799330104

Bazzano, M. 2005. To feel with the heart of another: Notes on Adler and Zen Buddhism. In P. Prina, A. Miller, C. Shelley, & K. John (Eds.), UK Adlerian Year Book 2005 (pp.42-54). The Adlerian Society UK Institute for Individual Psychology. https://manubazzano.com/wp-content/uploads/2020/11/adler-and-buddhism.pdf

Cantero-Sánchez, FJ, León-Rubio, JM, Vázquez-Morejón, R., & León-Pérez, JM 2021. Evaluation of an assertiveness training based on the social learning theory for occupational health, safety and environment occupational. Sustainability 13(20): 11504. https://doi.org/10.3390/su132011504

Case, B. 2024. Love's Limits in Paul of Tarsus and Seneca the Younger. Religions 15(10): 1169. https://doi.org/10.3390/rel15101169

Delaney, B. 2023. Reasons not to worry: how to be Stoic in chaotic times. Harper, 304pp. ISBN: 9780063314825 [=2024. Philosophy for living peacefully: A way of thinking for living in stressful times, learned from Stoicism. Discover Twenty-One, Tokyo. 421pp. ISBN: 9784799330784]

Ding, X., Ma, Y., Yu, F., & Abadal, LM 2023. The therapy of desire in times of crisis: lessons learned from Buddhism and Stoicism. Religions 14(2): 237. https://doi.org/10.3390/rel14020237

Dunbar, RI 2024. The social brain hypothesis–thirty years on. Annals of Human Biology 51(1): 2359920. https://doi.org/10.1080/03014460.2024.2359920

ElBarazi, AS, Mohamed, F., Mabrok, M., Adel, A., Abouelkheir, A., Ayman, R., … & Mohamed, F. 2024. Efficiency of assertiveness training on the stress, anxiety, and depression levels of college students (Randomized control trial). Journal of Education and Health Promotion 13(1): 203. https://doi.org/10.4103/jehp.jehp_264_23

Genschow, O., Cracco, E., Schneider, J., Protzko, J., Wisniewski, D., Brass, M., & Schooler, JW 2023. Manipulating belief in free will and its downstream consequences: A meta-analysis. Personality and Social Psychology Review 27(1): 52-82. https://doi.org/10.1177/10888683221087527

Goerger, M. 2017. Moral Practice in Late Stoicism and Buddhist Meditation. Comparative Philosophy 8(1): 7. https://doi.org/10.31979/2151-6014(2017).080107

Haidt, J. 2006. The happiness hypothesis: finding modern truth in ancient wisdom. Basic books, New York. 320pp. ISBN: 9780465028023 [=2011. The happiness hypothesis: ancient wisdom and modern scientific wisdom. Shin'yosha, Tokyo. 355pp. ISBN: 9784788512320]

Lavon, I., & Shifron, R. 2020. The use of early recollections in Adlerian psychotherapy: Evidence in neuroscience research. Psychology and Behavioral Science International Journal 15(2): 55590. http://dx.doi.org/10.19080/PBSIJ.2019.10.555908

Mack, NR, Deng, S., Yang, SS, Shu, Y., & Gao, WJ 2023. Prefrontal cortical control of anxiety: Recent advances. The Neuroscientist 29(4): 488-505. https://doi.org/10.1177/10738584211069071

Miller, R., & Dillman Taylor, D. 2016. Does Adlerian theory stand the test of time?: Examining individual psychology from a neuroscience perspective. The Journal of Humanistic Counseling 55(2): 111-128. https://doi.org/10.1002/johc.12028, https://scholarworks.boisestate.edu/cgi/viewcontent.cgi?article=1173&context=cifs_facpubs

Oda, Ryo & Otsubo, Yosuke. 2023. Expanding! Evolutionary Psychology. Asakura Shoten, Tokyo. 183pp. ISBN: 9784254523065

Pedersen, CA, Chang, SW, & Williams, CL 2014. Evolutionary perspectives on the role of oxytocin in human social behavior, social cognition and psychopathology. Brain Research 1580: 1-7. https://doi.org/10.1016/j.brainres.2014.07.033

Rasmussen, PR, & Dover, GJ 2006. The purposefulness of anxiety and depression: Adlerian and evolutionary views. The Journal of Individual Psychology 62(4): 366-396. ISSN: 1522-2527, https://psycnet.apa.org/record/2007-03417-003

Rogers, AR 1994. Evolution of time preference by natural selection. The American Economic Review 84(3): 460-481. https://www.jstor.org/stable/2118062

Termeer, CJ, & Dewulf, A. 2019. A small wins framework to overcome the evaluation paradox of governing wicked problems. Policy and Society 38(2): 298-314. https://doi.org/10.1080/14494035.2018.1497933

Tomono, Norio. 2006. Behavioral Economics: The Economy is Driven by "Emotions". Kobunsha, Tokyo. 397pp. ISBN: 9784334033545

Weick, KE 1984. Small wins: Redefining the scale of social problems. American Psychologist 39(1): 40-49. https://doi.org/10.1037/0003-066X.39.1.40

Villmoare, B., Klein, D., Liénard, P., & McHale, TS 2024. Evolutionary origins of temporal discounting: Modeling how time and uncertainty constrain optimal decision-making strategies across taxa. PloS One 19(11): e0310658. https://doi.org/10.1371/journal.pone.0310658

Yamamori, Y., Robinson, OJ, & Roiser, JP 2023. Approach-avoidance reinforcement learning as a translational and computational model of anxiety-related avoidance. Elife 12: RP87720. https://doi.org/10.7554/eLife.87720.4

When you take up listening to music, singing, or dancing as hobbies, you naturally become interested in rhythm and time signatures.

However, if we consider its origins, there are many aspects that we cannot answer. We often find ourselves moving to rhythms so naturally that we don't even question it, but this ability is actually very limited among living organisms, and it's fair to say that the ability to predict rhythm is unique to humans.

While there's no definitive answer as to the root cause of why that rhythm feels pleasant, one theory suggests that "walking" is deeply involved, and that it's also the origin of 2/4 and 4/4 time signatures. However, the concept of time signatures based on proper music theory itself only emerged in late medieval Europe with the birth of Baroque music.

The triple meter is considered unique and became widely used in 16th-century Austrian waltzes, supposedly because it matched movements that involved rotation.

This article will explain the origins of rhythm and time signatures (2/4, 4/4, and 3/4) from an evolutionary biological and historical perspective.

What is the origin of our sense of rhythm? Humans aren't the only ones who keep the beat!?

Rhythm is defined as "a phenomenon that repeats in a certain pattern that living beings can perceive."

The act of keeping rhythm is a phenomenon that is widely observed in organisms ranging from insects to monkeys, and there are examples such as the following (Iversen, 2016).

It's still unclear whether this sense of rhythm, from insects to humans, is due to genes that were common to all of them in evolutionary biology, but it seems that a certain degree of rhythmic sense is inherited.

What is the origin of the innate human sense of rhythm and the 2/4 time signature? Was the birth of walking the most important factor?

However, humans (and some birds) are thought to have developed a special sense of rhythm called "Rich BPS (Rich Beat Perception and Synchronization)" (Iversen, 2016).

Rich BPS consists of the following elements:

In short, it could be described as the ability to actively and predictively understand rhythm. It is currently believed that animals other than humans either lack this ability or possess it to a very limited extent.

So, what is considered to be the origin of Rich BPS and the 2/4 time signature?

Although there are various theories, walking is considered a very important factor (Iversen, 2016; Fitch, 2016).

For bipedal animals, the most energy-efficient form of walking is thought to be isochronic walking (walking with a constant period). Therefore, they move their left and right legs in a rhythmic manner.

It is believed that all humans, to varying degrees, instinctively acquire a sense of rhythm in order to grasp this sense of tempo.

There is a theory that the feeling of "pleasant rhythm" is an evolutionary by-product of "the motivation for infants to start walking."

Even adults sometimes feel a sense of comfort while taking a walk, which can be rephrased as finding the periodic vestibular and auditory inputs pleasant.

This theory suggests that the enjoyment of walking, stemming from periodic vestibular and auditory input, led to a preference for singing and dancing, which involve movements that stimulate the auditory and vestibular senses.

From another perspective, when bipedal animals walk in groups, if they can synchronize their walking rhythms, they may be able to quickly detect enemy groups, predators, or prey whose footsteps are not in sync. Furthermore, the size of the group can be concealed by layering sounds. This can also be considered a significant advantage of the evolution of Rich BPS.

In music theory, 2/4 time is monotonous because it consists only of strong and weak beats, and nowadays it is only used in marches, popular songs, and a few other genres, having largely given way to 4/4 time.

What is the origin of the 4/4 time signature?

4/4 time is a time signature with four beats per measure. It is similar to 2/4 time, but is generally distinguished by the fact that the strength of the beats progresses from strong to weak to medium-strong to weak. However, since the strength of the beats is not the sole definition of 4/4 time, it seems that the distinction is largely based on convention.

4/4 time, where a quarter note constitutes one beat, is the most widely used time signature in modern music and is used extensively in all genres, including rock, pop, dance music, classical, and jazz.

So, what do you think is the original origin of 4/4 time?

This is indeed considered to be walking (Fitch, 2016). However, the interpretation of walking changes slightly in this case.

When you're walking, you think of it as "sound of kicking with the right foot → sound of lifting the right foot → sound of kicking with the left foot → sound of lifting the left foot."

If we think about it this way, we get a time signature that follows the pattern of "strong beat → weak beat → strong beat → weak beat".

However, to the best of the author's knowledge, there are no papers that offer a clear explanation for the emergence of "mid-strong beats." While it's intuitively clear that the presence of "mid-strong beats" adds complexity and makes the music more enjoyable, it may remain a scientific mystery.

The "4/4 time signature" of "strong beat → weak beat → medium-strong beat → weak beat," based on modern music theory, is believed to have originated in the dance music of the early 17th century Baroque period, but its formation process is not well understood.

Even now, with the advent of DTM (Desktop Music) and the ability to reproduce any kind of music, the fact that even time signatures, along with the aforementioned 2/4 time signature, are still among the most widely used in pop music suggests that we instinctively prefer even time signatures, which resemble walking rhythms.

However, this approach alone cannot explain complex music that is not mainstream, such as music with irregular time signatures, groove, laid-back, push, offbeat, syncopation, and swing. While not mainstream, this music cannot be ignored and has achieved commercial success. While there's a strong sense that "being offbeat is more fun and comfortable," its biological origins remain a great mystery.

However, I also feel that these techniques are valuable when used in a partial manner.

What is the origin of the triple meter?

Triple time is a time signature with three beats per measure, consisting of a strong beat, a weak beat, and another weak beat. It is a time signature commonly used in Western dance music such as waltzes and minuets.

Typical time signatures include 3/4 time, where one beat is a quarter note, and 3/8 time, where two beats are eighth notes.

How did the triple meter come about?

While it may have originated even earlier, in Europe, mensural notation, which emerged in the late Middle Ages and early Renaissance, made it possible to accurately write the length of notes. It was then that, theoretically, triple time became possible.

In fact, the widespread use of triple time is believed to have originated in the waltz, at least in Europe (Fitch, 2016). There are various theories, but it is thought to have become popular in Europe around 1580 and developed from German and Austrian folk dances (Buurman, 2021). As a side note, the Japanese Wikipedia states that it was established in the 13th century, but there is no source for this, and there is no such statement in the English version.

In the Viennese waltz, a series of steps (step → turn → bring feet together) are interspersed between turns, with each "bringing feet together" action serving as a short break to prepare for the next step with the opposite foot. This creates a cycle of six steps, with both the right and left feet taking steps.

The unique aspect of this movement is that it involves rotation, and it is believed that a 3/4 time signature naturally becomes optimal when this action is involved.

Triple time can be considered a relatively new time signature, having emerged after the development of more relaxed dances.

What are some other theories about the evolution of rhythm?

There are several other theories regarding the evolution of rhythm, which I will introduce for reference (Iversen, 2016; Seki & Tachibana, 2023).

The Vocal Learning Hypothesis posits that a sense of rhythm evolved as a byproduct of the ability to imitate voices. This is supported by the fact that parrots and humans possess both the ability to imitate voices and a rich BPS (Beatman-Fetal Positioning System). However, this contradicts the fact that non-vocal mimicry animals (such as sea lions) also possess a sense of rhythm. This might simply be a pre-adaptation for acquiring neural circuits that convert auditory input into motor output.

The theory of sexual selection, proposed by the renowned evolutionary psychologist George Miller, suggests that musical ability was advantageous in mate selection. However, the fact that both sexes possess musical ability contradicts the typical theory of sexual selection. Nevertheless, since there are differences in musical preferences between men and women, it is possible that sexual selection occurred incidentally after the evolution of rhythmic sense.

The social bonding and group cooperation theory posits that rhythm evolved to promote group bonding and cooperative behavior. This seems natural when we consider the sense of unity we feel and the mosh pit we form at live concerts today. However, natural selection usually occurs among individuals or closely related groups, and this type of evolution falls under the category of "multilevel group selection," which is different from the usual pattern. This idea is not very popular in evolutionary biology because there is debate about its interpretation (although I think there is some truth to it). Moreover, it seems that rhythm is not the only thing that could promote bonding, so perhaps the sense of unity is a consequence of the evolution of rhythm.

The maladaptation theory (music being a byproduct) was proposed by the famous psychologist Steven Pinker, who argued that music is an "auditory cheesecake," a pleasure-seeking technique, and not an evolutionary adaptation. While it's true that modern, pleasant music might be like a cheesecake, the very sense of rhythm itself seems to be an evolutionary product.

Currently, the prevailing view seems to me that the fundamental sense of rhythm evolved in conjunction with walking, but this may change depending on future research.

References

Buurman, E. 2021. Early Viennese Waltz Dances. In: E. Buurman (Ed.), The Viennese Ballroom in the Age of Beethoven (pp. 32-54). Cambridge University Press. ISBN: 9781108797856, https://doi.org/10.1017/9781108863278.003

Fitch, WT 2016. Dance, music, meter and groove: a forgotten partnership. Frontiers in Human Neuroscience 10: 64. https://doi.org/10.3389/fnhum.2016.00064

Iversen, JR 2016. 21 In the beginning was the beat: evolutionary origins of musical rhythm in humans. In: R. Hartenberger (Ed.), The Cambridge Companion to Percussion (pp. 281-295). Cambridge University Press. ISBN: 9781107472433, https://doi.org/10.1017/CBO9781316145074.022

Seki, Yoshimasa & Tachibana, Ryosuke. 2023. Animal rhythm synchronization ability and its origins. Journal of the Acoustical Society of Japan 80(1): 33-40. https://doi.org/10.20697/jasj.80.1_33

Both Japanese broom (Cytisus scoparius) and dwarf broom (Cytisus erythrosora) belong to the legume family and are classified under the genus Cytisus in Japan. They are characterized by their small, trifoliate compound leaves and yellow, butterfly-shaped flowers that bloom in spring. In horticulture, they are cultivated for ornamental purposes, but dwarf broom is increasingly being sold under the name "Japanese broom," leading to more confusion. However, there is a crucial difference in the leaves, and checking this will prevent any mistakes. Japanese broom flowers are known to "burst" to release pollen onto bees. This article will explain the classification, morphology, and ecology of the genus Cytisus.

What are Broom and Cryptomeria japonica?

Cytisus scoparius, also known as broom or scoparius, is a deciduous shrub native to Europe that is cultivated worldwide for ornamental purposes and sometimes escapes cultivation. In Japan, it is commonly cultivated in gardens as an ornamental plant and sometimes escapes cultivation and becomes naturalized (Hayashi, 2019).

Genista x spachiana, also known as dwarf broom (Genista canariesis), is an evergreen shrub that is a horticultural hybrid of Genista canariesis and Genista stenopetala, native to the Canary Islands (off the northwest coast of Africa, a Spanish territory) (Sheppard et al., 2006). While the Ylist uses the scientific name Cytisus x spachianus, it is generally classified under the genus Genista. It is grown in warmer climates as a potted plant or garden tree.

Both belong to the legume family and are classified under the genus *Cytisus* in Japanese classification. They are characterized by having small, trifoliate compound leaves and producing yellow, butterfly-shaped flowers in the spring.

The Japanese name, originally genst or ginst in Dutch (derived from the Latin genista), was introduced to Japan during the Kyoho era of the Edo period. In Dutch studies books, it began to be written as enista, which later became enisuda with a voiced consonant, and the form genisuda appeared later, but ultimately it became enishida (Maeda, 2005).

Both are cultivated as ornamental plants in gardens, but many people may not be able to distinguish between the two species. The dwarf broom (Cytisus scoparius) is increasingly being sold under the name "Broom," leading to more confusion. They originate from different regions and are completely different species, so we want to reduce such misunderstandings.

What is the difference between Broom (Cytisus scoparius) and Dwarf Broom (Cytisus scoparius)?

The main difference between broom (Cytisus scoparius) and dwarf broom (Cytisus scoparius) lies primarily in their leaves (Hayashi, 2019).

Specifically, in broom (Cytisus scoparius), many leaves lack petioles, and there is a mixture of trifoliate and undivided leaves. The leaf tips are pointed, there are few hairs, and the leaves are dark green. In contrast, dwarf broom (Cytisus scoparius) has distinct petioles, only trifoliate leaves, the leaf tips are rounded, there are many hairs, and the leaves are light green.

Overall, broom (Cytisus scoparius) has a stiff appearance, and its leaves often grow straight upwards at an angle, but dwarf broom (Cytisus scoparius) has a softer appearance, and its leaves tend to droop.

Among the broom species, there is also the red-cheeked broom, Cytisus scoparius 'Andreanus', which has red keel petals on its flowers.

Currently, perhaps because of the abundance of flowers, the number of dwarf broom plants has increased considerably.

The "Ginette" in Plantagenet's name refers to the broom plant!?

Broom (Cytisus scoparius) has strong ties to European culture, and its yellow flowers are known as "golden flowers," highly valued for their beauty and hardiness.

The Plantagenet dynasty, which ruled England from 1154 to 1399, began when Henry II, Count of Anjou, of France, ascended to the English throne. The name Plantagenet comes from the French word "plante genêt," meaning "broom plant," and the word "genêt" comes from the Latin word "genista," meaning "broom."

As mentioned above, the Japanese word "enishida" can also be traced back to "genista," so they actually share the same etymology.

There are several theories as to why the name of the royal family was used for the broom plant. The most famous is that it was the nickname of Geoffrey V, Count of Anjou, the father of Henry II, Count of Anjou, and that he wore a broom plant in his hat.

While it is confirmed that it was a nickname for Geoffrey V, Count of Anjou, the story of him "wearing a broom in his hat" only became popular in the 16th and 17th centuries, and its etymological basis is weak. It has been suggested that it may have spread as a symbolic interpretation in later times (Plant, 2007).

One paper that points this out argues that while the possibility of using broom as a stab cannot be ruled out, it may have been used as a symbol of strong vitality, growth, and reproductive power, given its hairy buds and sturdy branches.

How is it pollinated? Do broom flowers "burst"?!

The pollination method of broom is typical of legumes, with butterfly-shaped flowers, and it is an insect-pollinated flower like other legumes (Tanaka and Hirano, 2000; Tanaka, 2001).

However, the pollination method is slightly different.

Butterfly-shaped flowers are divided into the standard petal (upper petal) and the wing petals (outer petals) and keel petals (inner petals) of the lower petals, and it is known that the wing petals reflect ultraviolet light.

In other words, while it appears as a uniformly yellow flower to humans, insects see the underside of the flower as having color.

Bees such as bumblebees, honeybees, and long-horned bees recognize these as nectar guides and are attracted to them, attempting to drink the nectar. However, broom flowers actually do not contain nectar.

The bee uses its middle and hind legs to brace itself on the keel petal of the broom flower, and this stimulation causes the keel petal to suddenly burst open, slamming the stamens and pistil that were contained within in a spring-like structure.

In this way, the broom plant successfully pollinates bees by sprinkling pollen from the tips of its stamens onto them, and by allowing pollen from other bees on their backs to adhere to the brooms.

It might seem that the lack of nectar is a disadvantage for the bees, but pollen is an important source of protein, so it's likely that the bees come specifically for this purpose.

References

Hayashi, Masayuki. (2019). Tree Leaves: Expanded and Revised Edition - Identifying 1300 Species Through Real-Life Scans. Yama-kei Publishers. ISBN: 9784635070447

Maeda, Tomoki. 2005. The Complete Dictionary of Japanese Etymology. Shogakukan. ISBN: 9784095011813

Plant, JS (2007). The tardy adoption of the Plantagenet surname. Nomina, 30, 57-84. ISSN: 0141-6340, https://www.snsbi.org.uk/Nomina_articles/Nomina_30_Plant.pdf

Sheppard, A., Haines, M., & Thomann, T. (2006). Native-range research assists risk analysis for non-targets in weed biological control: the cautionary tale of the broom seed beetle. Australian Journal of Entomology, 45 (4), 292-297. https://doi.org/10.1111/j.1440-6055.2006.00553.x

Tanaka, Hajime. (2001). Flowers and Insects: A Collection of Discoveries of Mysterious Deception. Kodansha. ISBN: 9784062691437

Tanaka, Hajime & Hirano, Takahisa. (2000). The Face of Flowers: Wisdom for Bearing Fruit. Yama-kei Publishers. ISBN: 9784635063043

Japanese walnut (Juglans mandshurica), Japanese walnut (Juglans regia), Japanese walnut (Juglans ventricosus), and Japanese walnut (Juglans rhoifolia) all belong to the Juglandaceae family and are deciduous trees characterized by odd-pinnately compound leaves with serrated edges. In addition to growing in Japanese forests, Japanese walnut, Japanese walnut, and Japanese walnut produce seeds called "walnuts" inside false fruits and hard fruits, making them indispensable in sweets and other dishes, although many people may not know the differences between them. The four species can be distinguished mainly by significant differences in their leaves and fruits. Japanese walnut is the one that is commonly sold today, but Japanese walnut and Japanese walnut have been used in Japan since ancient times and are part of local cuisine. This article will explain the classification, morphology, and ecology of the Juglans and Japanese walnut genera.

What are Japanese walnut, black walnut, small walnut, and Japanese walnut?

The Japanese walnut (Juglans regia), also known as the hand-beaten walnut, Persian walnut, Korean walnut, bear walnut, or Shinano walnut, is a deciduous tree native to Eastern Europe and Western Asia. In Japan, it is cultivated for food in Nagano Prefecture and the Tohoku region. It is cultivated worldwide for its edible seeds.

Japanese walnut (Juglans mandshurica var. sachalinensis) is a deciduous tree distributed in Hokkaido, Honshu, Shikoku, and Kyushu in Japan, as well as Sakhalin, and mainly grows in humid areas along rivers in the oak and chestnut zones.

Juglans mandshurica var. cordiformis, also known as the Japanese walnut (Juglans mandshurica var. cordiformis), is a deciduous tree found only in Japan, and is widely cultivated for its edible fruit.

Pterocarya rhoifolia, also known as Japanese walnut (Pterocarya rhoifolia), is a deciduous tree that grows in sandy and gravelly areas along rivers in mountainous regions, distributed in Hokkaido, Honshu, Shikoku, and Kyushu in Japan, as well as in Shandong Province in China.

Both belong to the walnut family and are deciduous trees characterized by odd-pinnately compound leaves with serrated edges.

The most distinctive feature is that in walnuts (Juglans mandshurica), Japanese walnuts (Juglans regia), and Japanese walnuts (Juglans spp.), a green outer layer derived from a fleshy receptacle covers the fruit, resulting in the formation of a false fruit (Shimizu, 2001).

This false fruit contains a true fruit (nut), which is a seed (also called a kernel, or what is commonly known as a "walnut") covered by a pericarp (the so-called "walnut shell").

When we think of cracking a nut, we picture a hard shell, but in reality, it's not the whole thing; you need to let the green outer skin of the false fruit rot in order to get it out.

The seeds have a rich flavor and are an essential part of mixed nuts for humans, but in nature, it is known that they are dispersed by caching food by small mammals such as squirrels and mice that can crack open the shells and eat the seeds.

However, there are many similar names, and many people may not know the differences between the species found in the forest, or which species is commonly sold as "walnut" in stores.

What are the differences between Japanese walnut, black walnut, Japanese walnut, and Japanese walnut?

First, although they all belong to the walnut family, they belong to different genera. Japanese walnut, black walnut, and dwarf walnut belong to the genus Juglans, while Japanese walnut belongs to the genus Pterocarya.

Therefore, there are differences in their basic structure (Hirono, 2008; Kanagawa Prefectural Flora Survey Association, 2018; Hayashi, 2019).

One difference between Japanese walnut (Juglans mandshurica), Japanese walnut (Juglans regia), and Japanese walnut (Juglans serrata) is that Japanese walnut (Juglans rhoifolia) produces drupes within pseudocarps, while Japanese walnut (Juglans mongolica) has samaras as its fruit.

Therefore, Japanese walnut trees are not used for food, and their seeds are dispersed by wind.

Of the remaining three species, the oak walnut (Juglans mandshurica) has large nuts and seeds that are brain-shaped with wrinkled surfaces, while the Japanese walnut (Juglans mandshurica) and Japanese walnut (Juglans regia) have smaller nuts and seeds that are not wrinkled and have a thick C-shape in cross-section.

Of the remaining two species, Japanese walnut (Onigurumi) has many wrinkles on the surface of its nuts and is round and acorn-shaped overall, while Japanese walnut (Himegurumi) has fewer wrinkles on the surface of its nuts and is flattened overall, with a pointed top, resembling a chestnut.

It is also possible to distinguish some species by their leaves.

All of these species have odd-pinnately compound leaves, but the difference lies in the leaflets: in Japanese walnut (Juglans mandshurica), the leaflets are entire, while in Japanese walnut (Juglans mandshurica), Japanese walnut (Juglans regia), and Japanese walnut (Juglans serrata), the leaflets have serrated edges.

Of the remaining three species, Japanese walnut and Japanese walnut have thick leaflets, are hairy, and have sparse, blunt serrations, while Japanese walnut has thin leaflets, is hairier, and has fine, blunt serrations.

No leaf-based distinctions have been found between Japanese walnut (Juglans mandshurica) and Japanese walnut (Juglans mandshurica). Therefore, they are considered to be varieties within the same species in terms of classification.

What are the differences in uses between Japanese walnut (Juglans mandshurica), Japanese walnut (Juglans regia), Japanese walnut (Juglans mandshurica), and Japanese walnut (Juglans rhoifolia)?

Walnut seeds are the most commonly eaten nuts worldwide, and mixed nuts usually contain walnuts. They are also eaten in dishes like walnut salad and as a garnish for sweets. As their distribution suggests, they have strong ties to Western culture.

On the other hand, in Japan, where the Japanese walnut (Juglans mandshurica) was not naturally distributed, the seeds of the Japanese walnut (Juglans mandshurica) were used, and large quantities of Japanese walnut shells have been unearthed from Jomon period archaeological sites (Watanabe, 1984). Although its use has decreased now, there are sweets and mochi (rice cakes) made with Japanese walnuts in the Chubu and Tohoku regions. They are sold under the name "Wagurumi" (Japanese walnut). Unlike Japanese walnuts, the seeds cannot be neatly extracted and must be poked out with a stick like an awl. The taste is described on websites as being more flavorful and richer than Japanese walnuts (Yatsugatake Chuo Kogen Shiki no Mori Sales Management Center, 2020).

Japanese walnut (Juglans mandshurica) is found only in Japan, and its seeds have been used as food in Japan. Some say that the seeds are easier to extract than those of the Japanese walnut (Juglans mandshurica), and that the taste is slightly milder compared to the Japanese walnut.

Japanese walnuts have winged fruits and are not typically eaten.

Are there any other similar types?

Pterocarya stenoptera resembles Pterocarya rhoifolia, but it is native to China, has even-pinnately compound leaves, and differs in that it has wings (green protrusions) on the leaf axis.

How do they disperse their seeds? They were the food source for 40% of Japanese squirrels!?

It is known that walnut seeds are dispersed by caching, carried out by small mammals such as squirrels and mice that can break the shells and eat the seeds (Tamura, 1997).

Squirrels and mice bury seeds in multiple locations underground as a way to preserve food for the winter. Some of these seeds are edible, but others are forgotten and germinate.

This is thought to be a result of co-evolution, as walnuts are intentionally targeted by the animals, and they also serve as an important winter food source for squirrels and mice.

In Japan, Japanese walnut trees are known to be dispersed by Japanese squirrels and field mice, and these two species are the only ones responsible for seed dispersal.

Some studies suggest that Japanese squirrels consume 40% of their annual diet of Japanese walnuts.

References

Hayashi, Masayuki. (2019). Tree Leaves: Expanded and Revised Edition - Identifying 1300 Species Through Real-Life Scans. Yama-kei Publishers. ISBN: 9784635070447

Hirono, Ikuo. (2008). Various types of walnuts. The names are rather confusing. Tree Walking Path 48. Wooden Notebook. https://kinomemocho.com/sanpo_kurumi.html

Kanagawa Prefecture Flora Survey Association. (2018). Kanagawa Prefecture Flora 2018 Electronic Edition. Kanagawa Prefecture Flora Survey Association. ISBN: 9784991053726

Shimizu, Takemi. (2001). Illustrated Dictionary of Botanical Terms. Yasaka Shobo. ISBN: 9784896944792

Tamura, Noriko. (1997). Storing and dispersal of Japanese walnut seeds by Japanese squirrels. Primate Research, 13 (2), 129-135. https://doi.org/10.2354/psj.13.129

Watanabe, Makoto. (1984). Herbivore in the Jomon Period (3rd enlarged edition). Yuzankaku Publishing. ISBN: 9784639003533, https://doi.org/10.11501/12205491

Yatsugatake Central Highlands Shikinomori Sales Management Center. (October 6, 2020). Japanese Walnut and Oak Walnut. Shikinomori News. https://www.alpico.co.jp/shikinomori/news/2020/10/post-322.php

Deutzia, Deutzia gracilis, and Deutzia crenata all belong to the genus Deutzia in the family Hydrangeaceae. It is believed that they were named "hollow trees" because their branches are hollow except for the young ones. In Japan, they have a history of being planted as a guide for rice planting and are said to be the origin of hedges. However, due to the increasing planting of Deutzia gracilis and the complexity of their classification, the three species are currently very often confused. The surest way to distinguish them is to check their leaves and flowers. You should be able to distinguish them relatively clearly. This article will explain the classification and morphology of the genus Deutzia.

What are Deutzia, Deutzia gracilis, and Deutzia crenata?

Deutzia crenata var. crenata, also known as Unohana, is a deciduous shrub distributed in Hokkaido, Honshu, Shikoku, and Kyushu in Japan, as well as in China. It grows in grasslands, forest edges, gravelly areas, and riverbanks, and is often planted as a hedge or along the edges of fields.

Deutzia gracilis var. gracilis, also known as Himeutsugi, is a deciduous shrub distributed in Honshu (west of the Kanto region), Shikoku, and Kyushu in Japan. It grows in relatively bright locations such as rocky areas along rivers and limestone areas, and is also planted as an ornamental plant in urban areas.

Deutzia scabra var. scabra, also known as round-leaved deutzia, is a deciduous shrub distributed in Honshu (west of the Kanto region), Shikoku, and Kyushu in Japan. It grows on sunny, somewhat dry slopes, such as cliffs on hillsides.

Both belong to the genus Deutzia in the family Hydrangeaceae, and it is believed that they were named "empty trees" because, except for the young branches, the inside of the branches is hollow.

Other common features include stellate hairs covering the entire body, opposite leaves, flowers that bloom from spring to early summer, five white petals, and capsule fruits.

As its alternative name "U-no-hana" suggests, the flowers bloom in Uzuki (the fourth month of the lunar calendar), and in Japan, the flowers of the deutzia have long been valued as a guide for rice planting. It is believed that they not only grew wild in the mountains and fields but were also planted around settlements and cultivated land (Miyauchi, 2010). Records in the Manyoshu indicate that it was used as a hedge during the Nara period, and current research suggests that it is the oldest plant species used as a hedge in Japan.

Although they are relatively uncommon plants these days, you can still see Deutzia gracilis planted in green spaces even in urban areas, and both species can be observed in forests.

However, due to this history and morphological similarities, Deutzia and Deutzia crenata are often confused, and it seems that few people understand how to correctly distinguish between them, including Deutzia gracilis. Incorrectly identified photos can be found on the internet.

Furthermore, there are many intraspecific varieties, and the classification is divided into very fine categories.

What are the differences between Deutzia, Deutzia crenata, and Deutzia gracilis?

Deutzia, Deutzia gracilis, and Deutzia crenata can be accurately distinguished by the shape of their leaves and flowers (Kanagawa Prefecture Flora Survey Association, 2018; Hayashi, 2019).

First, let's consider the leaves.

In Deutzia and Deutzia crenata, all the leaves are the same shape, petiolate, and elongated with a tail-like tip, whereas in Deutzia crenata, the leaves are somewhat dimorphic, with the leaves below the inflorescence being sessile and having a rounded base, and the overall shape being round.

As its name "Marubautsugi" suggests, this is easily recognizable and shouldn't pose much of a problem. While the leaves other than those below the inflorescence may have petioles, there isn't much difference in leaf shape, so it shouldn't be an issue.

The most confusing thing is distinguishing between Deutzia and Deutzia crenata.

However, there is a difference between Deutzia and Deutzia gracilis: Deutzia gracilis has thick, rough leaves that are grayish-green only on the upper surface, while Deutzia gracilis has thin leaves that are basically hairless with only a few stellate hairs, and the upper surface is bright green.

Touching it is probably the easiest way to tell. In the case of Deutzia gracilis cultivated in gardens, the leaf veins, especially the lateral veins, seem to be even more prominently white.

There are also differences in the flowers themselves. In particular, the filaments (the long, slender parts that support the anthers, which are the pollen-containing parts of the stamen) are important.

One difference between Deutzia and Deutzia gracilis is that Deutzia crenata has teeth on its filaments, while Deutzia gracilis does not.

The term "filament teeth" may be unfamiliar, but it's a special structure found only in certain members of the Deutzia genus. It involves rounded teeth located along the filament on the anther side, which contains the pollen.

Furthermore, in Deutzia, the teeth of the filaments grow almost perpendicular to the filament, whereas in Deutzia gracilis, the teeth of the filaments grow at an angle to the filament.

In addition, there is a difference in that the petals of Deutzia and Deutzia gracilis open horizontally to downwards, while those of Deutzia crenata open horizontally.

If you can observe the flowers and take pictures, that should be enough to distinguish them in this way.

What are the varieties of Deutzia?

Deutzia, Deutzia gracilis, and Deutzia crenata include numerous varieties and cultivars, but a complete list will be omitted here.

Deutzia crenata f. candidissima is a variety of Deutzia with white, double-flowered blossoms.

Deutzia crenata f. plena is a variety of Deutzia with white, double flowers and pinkish calyxes.

References

Hayashi, Masayuki. 2019. Tree Leaves: Expanded and Revised Edition - Identifying 1300 Species Through Real-Life Scans. Yama-kei Publishers, Tokyo. 824pp. ISBN: 9784635070447

Kanagawa Prefecture Flora Survey Association. 2018. Kanagawa Prefecture Flora 2018 (Electronic Edition). Kanagawa Prefecture Flora Survey Association, Odawara. 1803pp. ISBN: 9784991053726

Miyauchi, Yasuyuki. 2010. Cultural History of Keisen Trees (6): Deutzia. Horticultural Culture 7: 56-61. ISSN: 1882-5044, https://keisen.repo.nii.ac.jp/records/936

Poppies, including the common poppy, the thick-leaved poppy, the common poppy, and the long-headed poppy, all belong to the genus Papaver in the family Papaveraceae and are collectively known as poppies. They are very popular as ornamental plants because they produce beautiful, large single flowers and are widely cultivated. However, they are a difficult group to identify, despite being poisonous and prone to becoming naturalized. If you limit yourself to the four species, you can distinguish them relatively easily by focusing on the condition of the stems and leaves, the presence or absence of hairs, and the shape of the fruit. The Icelandic poppy is also often confused with them, but the Icelandic poppy has no stems or leaves. Poppies are a highly addictive type of narcotic and the raw material for opium, a useful painkiller, but it is known that the very existence of poppies has spurred human evolution. They have had a significant impact on history. This article will explain the classification, morphology, evolution, and history of the genus Papaver.

What are poppies, common poppies, field poppies, and long-headed poppies?

Poppy (Papaver somniferum subsp. somniferum) is also known as the somniferum species. Native to the western Mediterranean coast of Europe and North Africa, it does not exist in the wild and is an annual plant cultivated only by humans for food and medicinal purposes (Narita et al., 1998; Kanagawa Prefectural Flora Survey Association, 2018; Samorini, 2019; RBG Kew, 2025).

Papaver somniferum subsp. setigerum, also known as the Atsumi poppy, is native to the western Mediterranean coast of Europe and North Africa. It is known as a naturalized plant and has naturalized in various parts of the world. In Japan, it was reported in 1964 on the coast of the Atsumi Peninsula in Aichi Prefecture, and it is an annual plant that sporadically occurs in urban areas and wastelands from Honshu to Kyushu (Shimizu et al., 2001). It occasionally grows in urban areas, and photos of it being taken unknowingly and posted on Instagram have made headlines, as well as seedlings being sold under the mistaken impression of the Icelandic poppy.

Poppy (Papaver rhoeas), also known as the common poppy (Papaver rhoeas), is native to Europe, North Africa, and West Asia. In Japan, it was introduced as an ornamental plant during the Edo period and has since become naturalized as an annual or biennial plant.

Papaver dubium, also known as long-fruited poppy, is native to Europe, North Africa, and West Asia. In Japan, it was first recorded in Tokyo in 1961 (Yoshikawa, 2010). Seeds have been detected in imported grains, and its distribution has rapidly expanded since the 1990s due to unintentional introduction. It is now an annual plant found in a wide area from Hokkaido to Kyushu.

All of these belong to the genus Papaver in the family Papaveraceae, and are collectively known as poppies. They are very popular as ornamental plants because they produce beautiful, large single flowers, and are widely cultivated. The fact that their stigmas have 4 to 20 radiating lobes is also an interesting feature to look at.

[Seed Plant Encyclopedia #119] What are the species of the poppy family? Photo list

The Papaveraceae family consists of herbaceous plants whose stems and leaves are often covered in a powdery white substance. Breaking the stem releases a milky white or orange-yellow sap. The leaves are alternate, pinnately lobed or pinnately compound, sometimes simple, and lack stipules. The flowers are bisexual, radially symmetrical, or bilaterally symmetrical. The sepals are 2-4 in number and separate...

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Poricidal capsules, especially those of poppies called "poppy pods," are spherical fruits that, when ripe, develop a hole at the top edge, scattering their seeds. As the metaphorical expression "like poppy seeds" suggests, the seeds are extremely small and easily dispersed by wind (wind dispersal), sometimes leading to the introduction of invasive species.

All species contain multiple alkaloids that can cause skin irritation, and it is thought that they originally evolved to produce these alkaloids for defense against predators. Among these, opioids such as morphine, codeine, and thebaine act as psychotropic drugs when ingested by humans, but are also known to be addictive. The seeds also contain papaverine, an alkaloid different from opioids.

In Japan, poppies and Papaver dubium contain morphine, codeine, and thebaine, and are therefore designated as prohibited plants under the "Opium Law." Although not mentioned here, Papaver bracteatum, a related species, also contains thebaine and is therefore designated as a prohibited plant under the "Narcotics and Psychotropic Substances Control Law."

Poppies, in particular, have been cultivated by humans in the Mediterranean since the Neolithic period and have evolved to contain high levels of morphine and codeine. One could argue that they have proliferated by "turning humans into drug addicts," or in a negative sense, "plunging them into a swamp," as exemplified by the Sino-Japanese Wars and the subsequent Qing Dynasty and the Sino-Japanese War in Manchukuo.

However, it's not all bad. Morphine is used as an analgesic in surgical anesthesia and in end-of-life care involving severe pain, and codeine is used as a cough suppressant. Furthermore, papaverine is used to treat erectile dysfunction, smooth muscle spasms, and spasms associated with gastrointestinal disorders (Ashrafi et al., 2023).

The shichimi spice blend used to udon and soba noodles contains poppy seeds (actually seeds), and it's also sometimes found sprinkled on bread (Carlin et al., 2020). It would be difficult to completely dismiss such conveniences.

This group has both significant merits and demerits, and because there are many species, each with different characteristics, and they easily become feral, accurate identification is more important than with other species.

What are the differences between poppies, common poppies, field poppies, and long-headed poppies?

The methods for distinguishing these four species are explained in detail by the Ministry of Health, Labour and Welfare and the Tokyo Metropolitan Institute of Public Health (Ministry of Health, Labour and Welfare, 2019; Tokyo Metropolitan Institute of Public Health, 2008), so here we will present a concise method of distinction based on a key (Kanagawa Prefecture Flora Survey Association, 2018).

First, there is a difference in that the base of the stem leaves of poppies and Papaver dubium clasps the stem, whereas the base of the stem leaves of common poppies and long-headed poppies do not. Also, as will be discussed later, in poppies, the immature fruit enlarges, increasing the opiate content.

The difference between poppies and Papaver dubium is that poppies have hairless stems and leaves, while Papaver dubium has stiff hairs on its stems and leaves.

Regarding the common poppy (Papaver dubium) and the long-headed poppy (Papaver rhoeas), the fruit of the common poppy is nearly spherical, while that of the long-headed poppy is oblong. This is reflected in its Japanese name, "long-fruited poppy." Also, the petals of the common poppy are larger.

Regarding flower color, poppies come in various colors such as red, white, light pink, and purple; Papaver dubium comes in red; common poppies come in white, light pink, and red; and long-headed poppies come in orange-red.

The long-headed poppy, in particular, is an extremely common species in urban areas and is dominant over other species. However, it is only ever orange-red in color and usually does not come in other colors, so it is important to be able to distinguish it properly to avoid mistaking it for another species and damaging it.

The poppy that is most often mentioned as a plant that grows wild but is prohibited from cultivation is the American poppy (Papaver dubium). This most dangerous poppy was selectively bred by humans in ancient times and has evolved to be completely specialized for opium production. Without human intervention, it only rarely escapes into the wild and cannot normally reproduce in the wild. Keep this point in mind.

What's the difference between this and the Icelandic poppy?

The Icelandic poppy is generally considered the horticultural trade name for the Siberian poppy (Oreomecon nudicaulis). It is distributed in Turkestan, China, Korea, Mongolia, and Russia (including Siberia), and in Japan, it is a perennial plant cultivated only for ornamental purposes. However, it is not heat-tolerant and is treated as an annual plant sown in autumn in Japan.

The Siberian poppy was long known by the scientific name Papaver nudicaule, but a 2022 study, based on molecular phylogenetic analysis, renamed it to the above scientific name (Banfi et al., 2022).

Furthermore, contrary to its name, it is not naturally distributed in Iceland (although it is cultivated and has become naturalized). This is a common misconception, so caution is advised.

Icelandic poppies are also difficult to identify, and there have been incidents where seedlings of Papaver dubium (a type of poppy) were mixed in with Icelandic poppies.

How can we distinguish between them? There is actually a crucial difference (Wu et al., 2008).

In Icelandic poppies, all the leaves are basal leaves, whereas in the four species of poppy (Papaver dubium, Papaver rhoeas, Papaver cornii, and Papaver dubium), there are both stem leaves and basal leaves.

In other words, Icelandic poppies do not have leaves growing from their stems.

In addition, while the Icelandic poppy is originally a perennial, the common poppy, the thick-leaved poppy, the common poppy, and the long-headed poppy are all annuals. However, in Japan, both are considered annuals.

It should be noted that the cultivated "Icelandic poppy" is not the naturally occurring Siberian poppy, but rather has a complex origin, being a hybrid of species including the Arctic poppy (Papaver radicatum).

What is the history of the poppy? Were "Devil Fruits" actually evolved by humans themselves?!

The history of poppy use is ancient. Archaeological records based on the examination of seeds found at archaeological sites suggest that Neanderthals (Homo neanderthalensis), who are considered archaic humans and who partially interbred with modern humans (Homo sapiens), may have already been using them during the Late Paleolithic period (Jesus et al., 2023). However, this "poppy" is the wild form , Papaver somniferum subsp. setigerum.

It appears that Homo sapiens were still using the poppy seed during the Early Neolithic period.

Recent research indicates that domesticated poppies (Papaver somniferum subsp. somniferum), which have undergone a level of selective breeding that can be described as an evolutionary evolutionary change, increased in number during the Late Neolithic period (3300 BC to 2300 BC), and by the Late Bronze Age (around 1050 BC to 800 BC), most of the seeds remaining in archaeological sites had been replaced by poppies.

While its seeds may have been used for food, it is believed that its primary purpose from the beginning was as a narcotic. This is because, compared to the wild type of Papaver rhoeas, its fruits are larger and contain a higher amount of opiates, which are narcotic compounds.

After a single vibrant flower blooms, the poppy produces a fruit called a perforated capsule. In cultivated poppies, this immature perforated capsule becomes remarkably enlarged, and is called a "poppy bud" (Narita et al., 1998).

When a poppy seed pod is damaged, it secretes a white milky sap (latex), which turns brown and solidifies after about 20 minutes. This solidified sap is then scraped up with a bamboo spatula or similar tool and dried to produce what is called "raw opium."

Furthermore, if water is added or the mixture is heated, it becomes "opium."

Opium contains alkaloids called opiates, the most common being morphine, codeine, and thebaine.

Opioids are chemical substances synthesized from opiates using chemical methods (sometimes the term includes opiates themselves), and include diacetylmorphine (heroin), oxycodone, fentanyl, methadone, pethidine, tramadol, buprenorphine, and pentazocine.

Opioids exert their analgesic effect by binding to opioid receptors present throughout the nervous system. They act particularly strongly in the superficial layer of the spinal cord's dorsal horn, where opioid receptors are most densely concentrated, and in the brain, they have a psychotropic effect that induces euphoria through the descending pain inhibitory system.

Opioid receptors normally bind to endogenous opioids (such as endorphins, enkephalins, dynorphins, and endomorphin synthesized by the human body), and their role is to temporarily suppress pain in emergencies. Opioids cause a malfunction in this mechanism.

However, opioids are highly addictive, and inhaling high-purity opioids can lead to opioid use disorder (opioid addiction), essentially becoming a wreck. The horrific scenes of opium dens are well-known. Synthetic and semi-synthetic opioids, thanks to their chemical structure, can easily cross the blood-brain barrier and act directly on the brain, making them even more addictive (Le Couteur & Burreson, 2003).

During the cultivation of poppies, they developed poppy flower heads and increased their opiate content. However, this meant that nutrients were diverted to the production of these substances, making it difficult for them to survive in the wild without human intervention.

In this sense, ecologically speaking, the poppy has ultimately adopted a survival strategy of "parasitizing" the human nervous system. This interpretation is quite interesting.

From a human perspective, using it as a drug seems to offer no benefits, but just as some people in Japan today use alcohol and tobacco to stabilize their mental state, in ancient times it may have been one of the things that provided a sense of liberation or creativity (Prentis, 2022). Furthermore, raw opium is of lower purity than regular opium, so it may not have had the effect of turning people into addicts.

It was used in ancient Egypt and ancient Greece even after the dawn of recorded history, and cultivation continues to this day.

Its impact on history is significant, and it was abused during the Crimean War, the American Revolutionary War, and the Franco-Prussian War, giving rise to "soldier's disease" (Funayama, 2013).

Of all the major events, the Opium Wars are undoubtedly a must-mention. This war began in 1840 when Britain forced Qing China (present-day China) to trade in opium to prevent the outflow of silver from tea purchases.

Why is black tea preferred over green tea in the UK? Are flies the only ones that visit tea plant flowers?

Tea plants contain essential nutrients like catechins and caffeine, making them an indispensable beverage in Japan, enjoyed both at home and on the go. As you may know, its origin lies in China, and it's a species not native to Japan. However, even in China, wild varieties haven't been confirmed, which is puzzling...

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Furthermore, during the period leading up to and following the Sino-Japanese War, when the Japanese Empire expanded into China, the Manchukuo Asia Development Board implemented the "Great Opium Policy," officially promoting opium use, and the situation throughout China took on the appearance of what is sometimes called the "Sino-Japanese Opium War" (Eguchi, 1988; Kumano, 2019). The manga "Manchurian Opium Squad," which is based on this incident, is very thrilling and is one of my favorite manga.

Even today, opium is used as an analgesic and cough suppressant, and is cultivated under strict control. In Afghanistan, the largest producer, 6,000 tons of opium are produced annually on 250 hectares of land (Jesus et al., 2023). The Czech Republic, France, and Russia are also known as important producing regions.

References

Ashrafi, S., Alam, S., Sultana, A., Raj, A., Emon, NU, Richi, FT, … & Kim, B. 2023. Papaverine: a miraculous alkaloid from opium and its multimedicinal application. Molecules 28(7): 3149. https://doi.org/10.3390/molecules28073149

Banfi, E., Bartolucci, F., Tison, JM, & Galasso, G. 2022. A new genus for Papaver sect. Meconella and new combinations in Roemeria (Papaveraceae) in Europe and the Mediterranean area. Natural History Sciences 9(1): 67-72. https://doi.org/10.4081/nhs.2022.556

Carlin, MG, Dean, JR, & Ames, JM 2020. Opium alkaloids in harvested and thermally processed poppy seeds. Frontiers in Chemistry 8: 737. https://doi.org/10.3389/fchem.2020.00737

Eguchi, Keiichi. 1988. The Sino-Japanese Opium War. Iwanami Shoten, Tokyo. 209pp. ISBN: 9784004300298

Funayama, Shinji. 2013. The Science of Poison: The Relationship Between Poison and Humans - A Cultural and Historical Approach to How Poisons Have Been Used and Understood. Natsume Publishing, Tokyo. 239pp. ISBN: 9784816354090

Jesus, A., Bonhomme, V., Evin, A., Soteras, R., Jacomet, S., Bouby, L., & Antolín, F. 2023. Morphometrics of waterlogged archaeological seeds give new insights into the domestication and spread of Papaver somniferum L. in Western Europe. PloS One 18(5): e0286190. https://doi.org/10.1371/journal.pone.0286190

Kanagawa Prefecture Flora Survey Association. 2018. Kanagawa Prefecture Flora 2018 (Electronic Edition). Kanagawa Prefecture Flora Survey Association, Odawara. 1803pp. ISBN: 9784991053726

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