Genetic and anthropometric studies on Japanese people


In population genetics, research has been made to study the genetic origins of the modern Japanese people in Japan.
From the point of view of genetic studies, Japanese people:
From the point of view of anthropometric studies, Japanese people have:
A common origin of Japanese has been proposed by a number of scholars since Arai Hakuseki first brought up the theory and Fujii Sadamoto, a pioneer of modern archeology in Japan, also treated the issue in 1781. But after the end of World War II, Kotondo Hasebe and Hisashi Suzuki claimed that the origin of Japanese people was not the newcomers in the Yayoi period but the people in the Jōmon period. However, Kazuro Hanihara announced a new racial admixture theory in 1984. Hanihara also announced the theory "dual structure model" in English in 1991. According to Hanihara, modern Japanese lineages began with Jōmon people, who moved into the Japanese archipelago during Paleolithic times from their homeland in southeast Asia. Hanihara believed that there was a second wave of immigrants, from northeast Asia to Japan from the Yayoi period. Following a population expansion in Neolithic times, these newcomers then found their way to the Japanese archipelago sometime during the Yayoi period. As a result, miscegenation was common in the island regions of Kyūshū, Shikoku, and Honshū, but did not prevail in the outlying islands of Okinawa and Hokkaidō, and the Ryukyuan and Ainu people continued to dominate there. Mark J. Hudson claimed that the main ethnic image of Japanese people was biologically and linguistically formed from 400 BCE to 1,200 CE. Currently, the most well-regarded theory is that present-day Japanese are descendants of both the indigenous Jōmon people and the immigrant Yayoi people.
On the other hand, a research in October 2009 by the National Museum of Nature and Science et al. concluded that the Minatogawa Man, who was found in Okinawa and was regarded as evidence that the Jōmon people were not a homogenous group and that these southern Jōmon came to Japan via a southern route and had a slender and more neo-Mongoloid face unlike the northern Jōmon. Hiroto Takamiya of the Sapporo University suggested that the people of Kyushu immigrated to Okinawa between the 10th and 12th centuries CE.
A genetic autosomal study on the Jomon people showed that they are a unique group of the East Asian Mongoloid cluster and that they had genetic relations to modern Siberian and Native American samples.
A 2011 study by Sean Lee and Toshikazu Hasegawa reported that a common origin of Japonic languages had originated around 2,182 years before present.
A study conducted in 2017 by Ulsan University in Korea presented evidence that the genetic origin of Koreans is closer to that of southeast Asians. This was additionally supported by Japanese research conducted in 1999 that supported the theory that the origin of the Yayoi people was in southern China near the Yangtze river. This study further supports the already accepted admixture theory between the Jōmon and Yayoi populations.
The origins of the Jōmon and Yayoi people have often been a subject of dispute, and a recent Japanese publisher has divided the potential routes of the people living on the Japanese archipelago as follows:
However, a clear consensus has not been reached.
A recent genome study shows that modern Japanese do not have much Jōmon ancestry at all. Nuclear genome analysis of Jōmon samples and modern Japanese samples show strong differences.
Another study suggests that Yamato people have 14-20% Jōmon ancestry assuming that modern Ainu people descend from the Jōmon. The existence of two generations of Yayoi immigration were suggested. Earlier one is the immigrants of sea people from the area on the coast of the Yellow Sea possibly related to Siberian people or Southeast Asian people. Latter one is the immigrants via Korean peninsula and from the surrounding area of Shanghai.

Genetics

Anthropometry

Stephen Pheasant, who taught anatomy, biomechanics and ergonomics at the Royal Free Hospital and the University College, London, said that Far Eastern people have proportionately shorter lower limbs than European and black African people. Pheasant said that the proportionately short lower limbs of Far Eastern people is a difference that is most characterized in Japanese people, less characterized in Korean and Chinese people, and least characterized in Vietnamese and Thai people.
Rajvir Yadav et al. stated the sitting height to stature ratios of different populations: South Indian, female Indian, Eastern Indian, Southeastern African, Central Indian, US, Western Indian, German and Japanese.
Hirofumi Matsumura et al. and Hideo Matsumoto et al. said that the Japanese and Vietnamese people are regarded to be a mix of Northeast Asians and Southeast Asians who are related to today Austronesian peoples. But the amount of northern genetics is higher in Japanese people compared to Vietnamese who are closer to other Southeast Asians.
Neville Moray said that, for Korean and Japanese pilots, sitting height is more than 54% of their stature, with about 46% of their stature from leg length. Moray said that, for Americans and most Europeans, sitting height is about 52% of their stature, with about 48% of their stature from leg length. Moray indicated that modifications in basic cockpit geometry are required to accommodate Japanese and Vietnamese pilots. Moray said that the Japanese have longer torsos and a higher shoulder point than the Vietnamese, but the Japanese have about similar arm lengths to the Vietnamese, so the control stick would have to be moved 8 cm closer to the pilot for the Japanese and 7 cm closer to the pilot for the Vietnamese. Moray said that, due to having shorter legs than Americans, rudder pedals must be moved closer to the pilot by 10 cm for the Japanese and 12 cm for the Vietnamese.
Onuoha, Idike & Oduma stated the sitting height to stature ratios for the following ethnic populations: Southeastern Nigeria, Indian, German, British, Chinese and Japanese.

Craniometry

said that the "Mongoloid skull generally, whether Chinese or Japanese, has been rather more neotenized than the Caucasoid or European..."
Ann Kumar said that Michael Pietrusewsky said that, in a craniometric study, Borneo, Vietnam, Sulu, Java, and Sulawesi are closer to Japan, in that order, than Mongolian and Chinese populations are close to Japan. In the craniometric study, Michael Pietrusewsky said that, even though Japanese people cluster with Mongolians, Chinese and Southeast Asians in a larger Asian cluster, Japanese people are more closely aligned with several mainland and island Southeast Asian samples than with Mongolians and Chinese.
In a craniometric study, Pietrusewsky found that the Japanese series, which was a series that spanned from the Yayoi period to modern times, formed a single branch with Korea. Later, Pietrusewsky found, however, that Korean and Yayoi people were very highly separated in the East Asian cluster, indicating that the connection that Japanese have with Korea would not have derived from Yayoi people.
Park Dae-kyoon et al. said that distance analysis based on thirty-nine non-metric cranial traits showed that Koreans are closer craniometrically to Kazakhs and Mongols than to the populations in China and Japan.