Ancient eastward migration traced in genes

From "Eurasian Bookshelf" on Facebook -  

https://www.facebook.com/photo/?fbid=1202752154987561&set=a.527495192513264: A Story Written in DNA

The Development of the East Eurasian Phenotype

The East Eurasian phenotype — the set of physical traits common among many East Asian, Siberian, and some Southeast Asian populations — didn’t appear overnight. It developed over tens of thousands of years as ancient human populations adapted to diverse climates, diets, and environments across the vast lands east of the Eurasian Steppe.

Modern genetic studies suggest that many distinctive traits — including epicanthic folds, shovel-shaped incisors, thicker hair shafts, and skin tone variations — evolved as adaptive responses to cold climates, UV radiation, and dietary factors during the Upper Paleolithic (roughly 40,000–10,000 years ago).

These traits are believed to have crystallized among ancient hunter-gatherer populations in northern and eastern Asia, particularly in regions like Siberia, the Yellow River basin, and the Amur River valley. Later migrations spread this phenotype widely — into China, Korea, Japan, and Southeast Asia — blending with local groups over millennia.

Genetics also shows fascinating connections between East Eurasians and Native Americans, who migrated across Beringia during the Ice Age, carrying parts of this shared ancestry into the New World.

This story is still unfolding, thanks to ancient DNA research — revealing how migration, climate, and time have shaped the diversity of human appearance across continents.

TAIWAN, bridge to the Pacific islands; and the multiple impacts of climate change

Aside from archaeological finds, there are several other threads connecting prehistoric Taiwan with the spread of humans through the Pacific island chains.

One is the paper mulberry tree, native to Taiwan and Japan, which the Austronesian migrants took with them because they used its fibrous bark to make their cloth. A 2015 study of its genes supports the hypothesis that the species in Oceania are descended from those in Asia.
  https://raskisimani.files.wordpress.com/2013/01/broussonetia-paper-mulberry.pdf
  https://taiwantoday.tw/news.php?post=26541&unit=20%2C29%2C35&unitname=Taiwan-Review&postname=Austronesian-Roots&fbclid=IwAR0rEsePB0aR71MtPstwKguoqx-ZFsHNlw9r5JM0N0h1PbGW1kfIk849PF4

Another is linguistics. Professor Robert Blust https://en.wikipedia.org/wiki/Robert_Blust sorts the many languages of Taiwan into ten groups, only one of which (Malayo-Polynesian) developed into the Austronesian family of tongues.
  https://en.wikipedia.org/wiki/Austronesian_languages#Blust_(1999)
  https://en.wikipedia.org/wiki/Malayo-Polynesian_languages#Major_languages

A third is the study of human genes. A 2014 study of mitochondrial DNA from a c. 8,000-year-old skeleton unearthed on an island off the Chinese mainland links China to Taiwan and Austronesia.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3951936/

Figure 1: The Liangdao Man Skeleton (picture from here)

The same study suggests a prehistoric migration route as illustrated below, from an area where foxtail millet began to be cultivated (around what is now modern Beijing), to the region where rice was domesticated (surrounding modern Shanghai), to what is now Fuzhou on the mainland (1), on to Liangdao island (2), across to Taiwan (3) and then down to the Philippines (4) and beyond:

(Ibid., adapted from Figure 5)

How did these humans cross over from the mainland? At its narrowest, the Taiwan Strait is about 130 kilometres (80 miles) between Fujian and Taiwan.

Things were different in the last Ice Age. The Strait is now some 100 metres deep, but:
'Pleistocene glaciations lowered [the] sea level 140m in the East China Sea 15,000 years ago, forming a land bridge between Taiwan and the mainland, with Palaeolithic artifacts on both sides. In the initial Holocene 10,000 years ago, melting ice raised the East China Sea 100m, quickly forming the Taiwan Strait.' 
- from 'The Neolithic Taiwan Strait', by Kuang-chih Chang (1989)
https://web.archive.org/web/20120418153210/http://http-server.carleton.ca/~bgordon/Rice/papers/App.18ChangKC89.pdf

'Permafrost covered Asia as far south as Beijing,' says Wikipedia, so perhaps early humans were motivated to go further south, and some willing and able to walk over the exposed land between China and Taiwan.
https://en.wikipedia.org/wiki/Last_Glacial_Maximum#Asia

The end of the Ice Age saw rising sea levels: 'After the last ice age about 20,000 years ago, sea level initially rose due to the melting of the glaciers. That peaked around 4,000 to 5,000 years ago,' says geologist Chip Fletcher in this 2017 interview:
https://e360.yale.edu/features/as-seas-rise-tropical-pacific-islands-face-a-perfect-storm

One might think that this flooding was a spur to the development of boats, but although the earliest found by archaeological excavation date back 7,000 - 10,000 years, other evidence suggests that they existed tens of thousands of years earlier.
https://en.wikipedia.org/wiki/Boat#History
Indeed, recent finds in Central America suggest that homo sapiens may have arrived by sea 20,000 - 30,000 years ago and spread north and south from there, rather than coming though the Alaskan/Canadian ice corridor as previously thought:
http://polynesiantimes.blogspot.com/2020/07/origins-americas-first-colonised-in.html

Contrary to what one might assume, the post-glacial flooding was not uniform in all times and places. As the vast weight of ice was lifted from the land the continental plates started to shift about and rise up further from the Earth's mantle, like a ship being emptied of cargo. 'At the same time that Polynesians were undergoing their journeys of exploration and discovery, 1,000 to 3,000 years ago, sea level was falling and exposing coastal plains that then became habitable, where previously the sea was up against clay banks or cliffs,' says Fletcher. 'In the Pacific region [after c. 4,000-5,000 years ago], sea level started to fall until a few centuries ago. And now global warming is causing sea levels to rise again.'
https://e360.yale.edu/features/as-seas-rise-tropical-pacific-islands-face-a-perfect-storm

Although falling sea levels may have made it easier to land boats, 'around AD 1300 there was rapid global cooling, which was followed shortly by rapid sea-level fall – perhaps as much as 50-70 cm within 100 years in the Pacific [...]
   'In almost every island group in the Pacific - from Solomon Islands and Fiji in the west to Rapa and Easter Island in the east – the first signs of collapse appear around AD 1300 with almost all hill forts beginning to be occupied around AD 1400. [...] 
   'Rapid sea-level fall along Pacific island coasts would have lowered coastal water tables, slowed water circulation within lagoons and killed (through exposure) the most productive parts of coral reefs. A food crisis would have resulted for coastal dwellers. Conflict followed. So people fled inland where they stayed, more or less, for several hundred years.'
https://theconversation.com/rise-and-fall-social-collapse-linked-to-sea-level-in-the-pacific-56268

So the interaction between geography, climate and human history is unexpectedly complex.

TAIWAN: Pacific migration and the paperbark tree

'New evidence gleaned from the study of a common plant species lends further credence to the theory that Taiwan is the ancestral homeland of the Austronesian-speaking peoples,' says this 2015 article in Taiwan Today reporting on research that links Taiwan to a tree now found across the Pacific, the paper mulberry, used to make tapa cloth.



So on their skilled and dangerous voyages across the ocean, the Austronesian migrants must have taken not just food, tools and domestic animals but seeds and cuttings of the precious tree.

Photo taken from https://raskisimani.files.wordpress.com/2013/01/broussonetia-paper-mulberry.pdf

An interesting article on the tree, its history and uses can be found here:
https://raskisimani.files.wordpress.com/2013/01/broussonetia-paper-mulberry.pdf

TAIWAN: Headhunters display their latest victim

Found here

This photograph appeared on the Facebook page 'Philippine and world's indigenous tribes news and history' (20 March 2016) and at first glance the hunters celebrating behind the surprised and disappointed head might seem to be fist-bumping; instead it looks as though they are sharing something, or disguising their faces.

The accompanying text reads:

"HEADHUNTERS OF TAIWAN

Between 1903 and 1908 there were seventy advancements made to the guard lines by the Japanese, but indigenous men in search of heads often came over or under the barrier at nightfall to lay waiting in ambush for unsuspecting victims. Headhunting, the primary ritual component of the Atayal, Paiwan, Saiset, and other groups, not only served to maintain the prosperity of society by ensuring agricultural and community fertility through the propitiation of the deities and ancestors, it also ensured that a man would meet with success in finding a wife while at the same time guaranteeing his safe passage to the afterlife. Thus, the custom was considered indispensable to life and existence itself.

Among the Atayal, success met on the headhunt was deliberately marked upon the chins of warriors with tattoos. And those headhunters who acquired more than five heads using old weapons, like a curved machete-like knife, might also have their chests tattooed or the backs of their hands. Among the Paiwan, it was believed that the spirits of ancestors dwelled in these beheading knives, which were held in the possession of the tribe for several generations. However, the Paiwan were not necessarily tattooed after having taken a head; instead, the successful warrior was also denoted by the wearing of a certain kind of cap which was made by women of the tribe.

More generally, tattooing could also be administered to the foreheads of unmarried Atayal boys and girls in their teens. Apart from the tattooed foreheads of women, only those who were skillful in weaving could tattoo their cheeks and other parts of their bodies.

Besides the beautiful cloths they wove on the loom, Atayal women also manufactured net bags that headhunting husbands used to carry severed human heads. Next to his beheading knife, these bags were his most treasured possession.

It is not surprising, then, that the Atayal believed that only those women who were proficient in weaving (hence tattooed), and those men who were successful headhunters (also tattooed) could pass safely into the afterlife."

- but is taken from a longer - and interesting - post here that does not include the image above:

https://www.larskrutak.com/loosing-your-head-among-the-tattooed-headhunters-of-taiwan/