This episode is focused on discussion of the recent paper “Ancient genomics reveals tripartite origins of Japanese populations” by Cooke, et al, which many people are claiming is “re-writing” ancient Japanese history. But what history is it re-writing and what do their findings mean for us, going forward?

Geography

So first off, there is a lot of talk about various locations on the mainland that we don’t normally cover, so we’ll have some maps here to help out.

So one of the places we will be discussing is the West Liao River Basin. The Liao river runs into the Yellow sea on the western side of the Liaodong peninsula (in fact, Liaodong can be translated as basically “east of Liao”). The River Basin includes the various rivers and tributaries that flow into the Liao River and then on into the ocean. Three of the individuals from the continent that the researches compared DNA to were from the Longtoushan site, a bronze age site in the West Liao River Basin, hence the nomenclature of WLR_BA and WLR_BA_o. The first referring to the two individuals with significant DNA matches to populations in the Yellow River Basin while the second referred to the one individual with DNA that indicated ancestry in the Amur River Basin. This was the individual who most closely matched with the Yayoi samples on the archipelago.

This next map is extremely general, and shows what seems to be the general gene flow into the archipelago, based on the latest research. There is a flow that comes from Southeast Asia up north and into Japan from the earliest period of migration, which likely happened from ~38,000 to ~16,000 years ago. Then there is gene flow detected from what seems to be the Amur River Basin, possibly passing through Western Liao River Basin before making its way to the islands around the time of the Yayoi, about ~3,000 years ago—around 900 BCE, when rice first starts to show up as a crop on the archipelago. Finally, we have gene flow from the Yellow River Basin sometime between the Yayoi and the late Kofun period, between roughly the 3rd and 7th centuries CE. By the end of the Kofun the genetic makeup of the Japanese population appears to be fairly stable up through the modern day, with only slight variation as compared with earlier populations.

Previous Episodes

If you want to go back and listen to some of the episodes that may be relevant to the discussion, here’s a brief, non-exhaustive list:

• Episode 1 - Pre-historic Japan

  • Perhaps a bit of a misnomer since we stayed in pre- or proto-history for quite some time—many even still count proto-history up until the actual publication of the Chronicles themselves. Anyway, in this first episode we talked about Minatogawa Man and the earliest traces of homo sapiens on the archipelago, including how they may have got there.

• Episode 5 - Goggle Eyes and Wet Earwax

  • Episodes 2 through 5 were all about the Jōmon, and in our fifth episode we talked about what we learned from the DNA sequencing of the woman from Rebun island, off the coast of Hokkaidō. She is one of the previously sequenced genomes that this study used in their research and analysis.

• Episode 7 - Rice comes to Japan

  • Though we touched on some of the continental movements in Episode 6 and the birth of rice agriculture in the Korean peninsula, Episode 7 is where we really see rice coming over to Japan and the start of the Yayoi period. This is presumably when the Amur River ancestry makes its way into Japan.

• Episode 8 - Bronze and Iron

  • Here is where we discussed the establishment of Lelang and the various Han commanderies on the Korean Peninsula, though it is at the very end of the episode. The fact that the commanderies were established in 108 BCE, though, means that while they could have brought Yellow River DNA with them, it was much too late for the first wave to cross over to the archipelago about 800 years prior.

• Episode 9 - The Langauge of Wa

  • This is one area where I think we definitely have some questions to ask ourselves. If the early Yayoi were people with Amur River ancestry, then did they bring the language of “Wa”—that is to say, Japonic—with them or did the origins of Japanese in the archipelago come later? It is still possible that there is a link to the Shandong peninsula, but if so, perhaps the Japonic language families didn’t come in until some time after people with Yellow River Basin ancestry arrived. We certainly see traces of what looks to be Japonic in the names used for the countries of Japan in the mainland accounts, so it would seem to have been established by that time, but who brought it to the islands, and when?

• Episode 30 - Yamato and the Continent

  • For about 21 episodes we covered the Age of the Gods and various legendary—possibly mythic—sovereigns, finally coming back to the connections with the continent—something that we touched on throughout, but here we talked about some of the evidence in the Chronicles pointing to emigration from the peninsula from a very early period.

• Episode 39 - Birth of the Three Kingdoms

  • This was the episode we concentrated on what was going on over on the mainland, including the destruction and collapse of the commanderies, leading to an apparent diaspora of the ethnic Han citizens across the peninsula and over into the archipelago.

References

• Cooke, N. P., Mattiangeli, V., Cassidy, L. M., Okazaki, K., Stokes, C. A., Onbe, S., ... & Nakagome, S. (2021). Ancient genomics reveals tripartite origins of Japanese populations. Science Advances, 7(38), eabh2419. DOI: 10.1126/sciadv.abh2419

• Ning, C., Li, T., Wang, K., Zhang, F., Li, T., Wu, X., ... & Cui, Y. (2020). Ancient genomes from northern China suggest links between subsistence changes and human migration. Nature communications, 11(1), 1-9. DOI: 10.1038/s41467-020-16557-2

• HANIHARA, K. (1991). Dual Structure Model for the Population History of the Japanese. Japan Review, 2, 1–33. http://www.jstor.org/stable/25790895

• -, -. (2020). A History of Crainiology in Race Science and Physical Anthropology. The Penn Museum Website. Last viewed on 9/28/2021. https://www.penn.museum/sites/morton/craniology.php