A paper (Using hominin introgression to trace modern human dispersals, Joao C. Teixeira and Alan Cooper, PNAS first published July 12, 2019 https://doi.org/10.1073/pnas.1904824116 - behind a pay wall), reports admixture with several groups of hominins other than Denisovans and Neanderthals during the dispersal of modern humans around the globe.
The abstract says the following:
"bstract The dispersal of anatomically modern human populations out of Africa and across much of the rest of the world around 55 to 50 thousand years before present (ka) is recorded genetically by the multiple hominin groups they met and interbred with along the way, including the Neandertals and Denisovans. The signatures of these introgression events remain preserved in the genomes of modern-day populations, and provide a powerful record of the sequence and timing of these early migrations, with Asia proving a particularly complex area. At least 3 different hominin groups appear to have been involved in Asia, of which only the Denisovans are currently known. Several interbreeding events are inferred to have taken place east of Wallace’s Line, consistent with archaeological evidence of widespread and early hominin presence in the area. However, archaeological and fossil evidence indicates archaic hominins had not spread as far as the Sahul continent (New Guinea, Australia, and Tasmania), where recent genetic evidence remains enigmatic."
Apparently the following admixture events took place between our unchaste ancestors and the other humans they met during their travels:
- Neanderthals: in the Middle East (?) 50 - 55 kya
- Unknown human similar to Neanderthals and Denisovans. More recent than 50 kya. In Northern India. Modern Punjabi and Bengal populations have some DNA from this admixture event.
- Humans that headed into Central and Eastern Asia: Admixture with Denisovans.
- Humans heading south into the Malaysian Peninsula: mixed with a relative of the Denisovans which had split from those living in Central Asia some 280 kya. This introgression took place in Malaysia or Borneo.
- This group split: those heading into the Philippines mixed with yet another group of Denisovans and the hunter-gatherers living there nowadays carry this genetic imprint.
- The group heading south towards Australia met some humans which were not Homo erectus, or Neaderthal or Denisovan, they were not the Flores "Hobbit" either. The genetic signals of this archaic group has been found int he short-statured people living on Flores nowadays.
Nobody seems to have admixed with the other known species of that region: the Homo luzonensis (from the Philippines) and the Flores Island hobbits.
The following images are from this paper:
These unknown hominins are indeed a very interesting find! We will have to await for further studies to learn more about them.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2019 by Austin Whittall ©
Dear Austin, I've been thinking, deeply about when humans left Africa. Or indeed whether there was more than one centre of evolution for early hominids.
ReplyDeleteThe I remembered this paper about 2.6 million year old stone tools from Pakistan. Ref: Dambricourt Malassé, A., et al., Anthropic activities in the fossiliferous Quranwala Zone, 2.6 Ma, Siwaliks of Northwest India, historical context of the discovery and scientific investigations. C. R. Palevol (2016), http://dx.doi.org/10.1016/j.crpv.2015.06.004.
Have you read it? NeilB
Thank you NeilB, the information sounds interesting! No I haven't read the paper, but I will. Judging by the age -2.6 Million years this can only mean Homo habilis or perhaps an even earlier (australopithecine?) OOA event. Very interesting
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