Today Science Advances published a paper (Morphology of the Denisovan phalanx closer to modern humans than to Neanderthals, E. Andrew Bennett et al., Science Advances 04 Sep 2019: Vol. 5, no. 9, eaaw3950 DOI: 10.1126/sciadv.aaw3950), which looked into the morphology of a Denisovan finger bone and compared it to that of modern humans and neanderthals.
Surprisingly it is more similar to ours than to the Neanderthals' finger bones even though Denisovan and Neanderthal DNA is closer to each other than to us.
The authors state: "Our morphometric analysis shows that its dimensions and shape are within the variability of Homo sapiens and distinct from the Neanderthal fifth finger phalanges. Thus, unlike Denisovan molars, which display archaic characteristics not found in modern humans, the only morphologically informative Denisovan postcranial bone identified to date is suggested here to be plesiomorphic and shared between Denisovans and modern humans.".
Neanderthals had fingers with wider ends (or tufts), which were also longer -in proportion- than ours. The Denisovan finger bone falls within the dimensions and proportions of modern human fingers and is very different to that of their relatives, the Neanderthals.
The paper concludes:
"
The nuclear genomes of Neanderthals and Denisovans are closer to each other than to modern humans, and it has been estimated that the population split time between Denisovans and Neanderthals is about 410 ka ago, whereas the population split time between these archaic humans and the ancestors of AMHs is about 580 ka ago ... Despite being evolutionary sister groups, the Denisova 3 DP5 does not exhibit any of the features seen in Neanderthals. Its morphology is indistinguishable from that of modern humans and located within modern human variation, which likely represents the plesiomorphic morphology of nonpollical DPs within the genus Homo as seen in both the Olduvai Hominin OH 7 and the Dmanisi hominins. This suggests that the Neanderthal-specific characters of the phalanx evolved after the divergence of Denisovans and Neanderthals. The only Neanderthal DP5 that falls in the middle of the modern human variation is from Moula-Guercy, one of the earliest members of the Neanderthal lineage from our sample dating to around 100 ka ago. This observation raises the possibility that the derived properties of the Neanderthal phalanx occurred rather late during the evolution of the Neanderthals. The similarity between the Denisovan phalanx and those of AMHs contrasts with the morphology of the molars of the Denisova individuals that are morphologically closer to more archaic humans from the Middle Pleistocene to the Late Pleistocene... This finding calls for caution when identifying potential Denisovan postcranial skeletal remains beyond Denisova, as their morphology might be ambiguous or more similar to modern humans than to Neanderthals."
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