現存する最古の文明

Hannah Devlin “Indigenous Australians most ancient civilisation on Earth, DNA study confirms” https://www.theguardian.com/australia-news/2016/sep/21/indigenous-australians-most-ancient-civilisation-on-earth-dna-study-confirms


コペンハーゲン大学のEske Willerslev 氏(進化遺伝学)*1らの研究は、現在の濠太剌利アボリジニ*2やパプア・ニューギニアの先住民*3が最初にアフリカ大陸を離れ・この地に到達した人類(ホモ・サピエンス)の子孫であることを証明した*4

Willerslev’s findings, based on a new population analysis of 83 Indigenous Australians and 25 Papuans, shows that these groups can trace their origins back to the very first arrivals on the continent about 50,000 years ago and that they remained almost entirely isolated until around 4,000 years ago. “They are probably the oldest group in the world that you can link to one particular place,” said Willerslev.

En route to Australia, early humans would have encountered a motley assortment of other roving hominin species, including an unknown human relative who has now been shown to have contributed around 4% to the Indigenous Australian genome. Previously, scientists have discovered that prehistoric couplings have left all non-Africans today carrying 1-6% of Neanderthal DNA*5.

Willerslev said the latest findings added to the view that Neanderthals and other now extinct hominins, traditionally portrayed as low-browed prehistoric thugs, were “in reality not particularly different” from our own ancestors.

また、

Willerslev’s study also resolves the apparent discrepancy between genetic findings implying that Indigenous populations have been in Australia for tens of thousands of years and the fact that the languages spoken by these populations are only around 4,000 years old. “You see a movement of people spreading across the continent and leaving signatures across the continent,” said Willerslev. “That is the time that this new language has spread. It’s a tiny genetic signature. It’s almost like two guys entering a village and saying ‘guys, now we have to speak another language and use another stone tool and they have a little bit of sex in that village and then they disappear again.”
当事者(のひとり)のコメント;

Aubrey Lynch, an Indigenous elder from the Goldfields area, said: “This study confirms our beliefs that we have ancient connections to our lands and have been here far longer than anyone else.”

Nature に同時に掲載されたハーヴァードのSwapan Mallick 氏らの研究*6


Adding to this picture, a second study found that the advent of modern human behaviours around 100,000 years ago, indicated by cave art and more sophisticated tools, does not appear to have been accompanied by any notable genetic mutations.

“Your genome contains the history of every ancestor you ever had,” said Swapan Mallick, a geneticist at Havard Medical School who led the analysis of the genomes of people from 142 distinct populations.

The study also suggests that the KhoeSan (bushmen) and Mbuti (central African pygmies) populations appear to have split of from other early humans sooner than this, again suggesting that there was no intrinsic biological change that suddenly triggered human culture.

“There is no evidence for a magic mutation that made us human,” said Willerslev.

Chris Stringer, head of human origins at the Natural History Museum in London*7, said the findings would be controversial in the field, adding: “It either means that the behaviours were developed earlier, they developed these behaviours independently, they acquired them through exchanges of ideas with other groups, or the estimated split times are too old.”

*1:See eg. http://geogenetics.ku.dk/staff/?pure=en/persons/26558 https://en.wikipedia.org/wiki/Eske_Willerslev

*2:Mentioned in http://d.hatena.ne.jp/sumita-m/20070922/1190483487 http://d.hatena.ne.jp/sumita-m/20091101/1257084108 http://d.hatena.ne.jp/sumita-m/20091129/1259486683 http://d.hatena.ne.jp/sumita-m/20120223/1330012587 http://d.hatena.ne.jp/sumita-m/20160328/1459185673

*3:Mentioned in http://d.hatena.ne.jp/sumita-m/20070604/1180988103 http://d.hatena.ne.jp/sumita-m/20091127/1259322730 http://d.hatena.ne.jp/sumita-m/20100629/1277839222

*4:Anna-Sapfo Malaspinas, Michael C. Westaway, Craig Muller, Vitor C. Sousa, Oscar Lao, Isabel Alves, Anders Bergström, Georgios Athanasiadis, Jade Y. Cheng, Jacob E. Crawford, Tim H. Heupink, Enrico Macholdt, Stephan Peischl, Simon Rasmussen, Stephan Schiffels, Sankar Subramanian, Joanne L. Wright, Anders Albrechtsen, Chiara Barbieri, Isabelle Dupanloup, Anders Eriksson, Ashot Margaryan, Ida Moltke, Irina Pugach, Thorfinn S. Korneliussen et al. “A genomic history of Aboriginal Australia” http://www.nature.com/nature/journal/vaop/ncurrent/full/nature18299.html

*5:See Ian Sample “Ancient human bone helps date our first sex with Neanderthals” http://www.theguardian.com/science/2014/oct/22/ancient-human-bone-sex-neanderthals-oldest-genome-dna Mentioned in http://d.hatena.ne.jp/sumita-m/20141025/1414203059

*6:Swapan Mallick, Heng Li, Mark Lipson, Iain Mathieson, Melissa Gymrek, Fernando Racimo, Mengyao Zhao, Niru Chennagiri, Susanne Nordenfelt, Arti Tandon, Pontus Skoglund, Iosif Lazaridis, Sriram Sankararaman, Qiaomei Fu, Nadin Rohland, Gabriel Renaud, Yaniv Erlich, Thomas Willems, Carla Gallo, Jeffrey P. Spence, Yun S. Song, Giovanni Poletti, Francois Balloux, George van Driem, Peter de Knijff et al. “The Simons Genome Diversity Project: 300 genomes from 142 diverse populations” http://www.nature.com/nature/journal/vaop/ncurrent/full/nature18964.html

*7:http://www.nhm.ac.uk/our-science/departments-and-staff/staff-directory/chris-stringer.html See also http://d.hatena.ne.jp/sumita-m/20110901/1314903862 http://d.hatena.ne.jp/sumita-m/20151216/1450238834