Content deleted Content added
→Environmental adaptations: Fixed grammar; rewrote awkward sentence(s) Tags: Mobile edit Mobile app edit Android app edit |
m Dating maintenance tags: {{Cn}} |
||
| (One intermediate revision by one other user not shown) | |||
Line 112:
The [[dingo]] reached Australia about 4,000 years ago. Near that time, there were changes in language (with the [[Pama-Nyungan languages|Pama-Nyungan language family]] spreading over most of the mainland), and in [[stone tool]] technology. Smaller tools were used. Human contact has thus been inferred, and genetic data of two kinds have been proposed to support a gene flow from India to Australia: firstly, signs of South Asian components in Aboriginal Australian genomes, reported on the basis of genome-wide [[Single-nucleotide polymorphism|SNP]] data; and secondly, the existence of a [[Y chromosome]] (male) lineage, designated [[haplogroup]] C∗, with the most recent common ancestor about 5,000 years ago.<ref name=bergstrom2016/>
The first type of evidence comes from a 2013 study by the [[Max Planck Institute for Evolutionary Anthropology]] using large-scale [[genotyping]] data from a pool of Aboriginal Australians, New Guineans, island Southeast Asians, and Indians. It found that the New Guinea and [[Mamanwa]] (Philippines area) groups diverged from the Aboriginal about 36,000 years ago (there is supporting evidence that these populations are descended from migrants taking an early "southern route" out of Africa, before other groups in the area).{{cn|date=July 2024}} Also the Indian and Australian populations mixed long before European contact, with this gene flow occurring during the Holocene ({{c.}} 4,200 years ago).<ref name=maxplanck2013>{{cite journal |last1=Pugach |first1=Irina |last2=Delfin |first2=Frederick |last3=Gunnarsdóttir |first3=Ellen |last4=Kayser |first4=Manfred |last5=Stoneking |first5=Mark |title=Genome-wide data substantiate Holocene gene flow from India to Australia |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=110 |issue=5 |date=29 January 2013 |pages=1803–1808 |pmid=23319617 |doi=10.1073/pnas.1211927110 |pmc=3562786 |bibcode=2013PNAS..110.1803P |doi-access=free }}</ref> The researchers had two theories for this: either some Indians had contact with people in Indonesia who eventually transferred those Indian genes to Aboriginal Australians, or a group of Indians migrated from India to Australia and intermingled with the locals directly.<ref>{{Cite book|title=The ocean of churn : how the Indian Ocean shaped human history| last=Sanyal| first=Sanjeev |date=2016 |isbn=9789386057617|location=Gurgaon, Haryana, India|pages=59|oclc=990782127 | publisher=Penguin UK}}</ref><ref name="MacDonald"/>
However, a 2016 study in ''[[Current Biology]]'' by Anders Bergström et al. excluded the Y chromosome as providing evidence for recent gene flow from India into Australia. The study authors sequenced 13 Aboriginal Australian Y chromosomes using recent advances in [[Whole genome sequencing|gene sequencing]] technology. They investigated their divergence times from Y chromosomes in other continents, including comparing the haplogroup C chromosomes. They found a divergence time of about 54,100 years between the Sahul C chromosome and its closest relative C5, as well as about 54,300 years between haplogroups K*/M and their closest haplogroups R and Q. The deep divergence time of 50,000-plus years with the South Asian chromosome and "the fact that the Aboriginal Australian Cs share a more recent common ancestor with Papuan Cs" excludes any recent genetic contact.<ref name=bergstrom2016/>
| |||