Denisovans were an archaic hominin species that was a sister to Neanderthals and admixed with modern humans in Southeast Asia. Previously, Denisovan remains were found in Siberia and Tibet.
Now, the tooth of a Denisovan female which is at least 131,000 years old, was found in Cobra Cave in Laos. The species identification and gender were based upon morphology and tooth enamel proteins, rather than ancient DNA per se. The presence of Denisovan's in the region was expected based upon Denisovan DNA in Asians and Australians and Papuans. The New York Times discusses the find further.
The paper and its abstract are as follows:
The Pleistocene presence of the genus Homo in continental Southeast Asia is primarily evidenced by a sparse stone tool record and rare human remains. Here we report a Middle Pleistocene hominin specimen from Laos, with the discovery of a molar from the Tam Ngu Hao 2 (Cobra Cave) limestone cave in the Annamite Mountains. The age of the fossil-bearing breccia ranges between 164–131 kyr, based on the Bayesian modelling of luminescence dating of the sedimentary matrix from which it was recovered, U-series dating of an overlying flowstone, and U-series–ESR dating of associated faunal teeth. Analyses of the internal structure of the molar in tandem with palaeoproteomic analyses of the enamel indicate that the tooth derives from a young, likely female, Homo individual. The close morphological affinities with the Xiahe specimen from China indicate that they belong to the same taxon and that Tam Ngu Hao 2 most likely represents a Denisovan.
Fabrice Demeter, et al.,"A Middle Pleistocene Denisovan molar from the Annamite Chain of northern Laos" 13 Nature Communications volume 13, Article number: 2557 (May 17, 2022) (open access).
14 comments:
Not far from Tam pa ling cave with early pygmoid Hs skull ~ 60ka, maybe woth Denisovan mixture.
Perhaps.
https://sciendo.com/de/article/10.2478/anre-2021-0029
A weird study. Apparently, H. erectus brains were just as big as the lower half of modern human population's brains. Big overlap. Since intelligence in modern humans is only slightly correlated with brain size, it hints that H. erectus may have been about as smart as we are. Thought it might amuse you.
are humans a type of H. erectus
On what basis do you make that claim? Do you think H erectus had ape chromosomes rather than Hs?
H. erectus and H. sapiens could probably not have produced offspring.
doesn't human neanderthal and Denisovan dna have archaic dna as in erectus
"H. erectus and H. sapiens could probably not have produced offspring."
Denisovans seem to have produced offspring with H. erectus and they were essentially just as distant to H. erectus as we are.
humans descended from H. erectus
On what basis do you make that claim?
Time depth to H. erectus-H. sapiens split is about four times what it was with H. sapiens-H. neanderthal and H. sapiens-Denisovan, and the H. neanderthal admixture show signs of classic hybrid incompatibility (e.g. probably only female offspring were fertile) so much more distant would have been likely incompatible, when neanderthal admixture was on the margins.
Also, no direct admixture from H. erectus, despite a decent possibility of them existing briefly at the same time given increasingly earlier evidence of Out of Africa (H. erectus existed through about 100 kya and the earliest Out of Africa dates are in that range), and given the lack of admixture likely co-existence of H. erectus and H. sapiens at the same time in Africa given earlier (the earliest H. sapiens in Africa are ca. 300 kya to 250 kya).
As neo notes, H. sapiens are probably descendants of H. erectus, but at incredible time depth with intermediate species between them.
The time depth of the Denisovan-H. erectus split is considerably less by on the order of 500kya than the modern human -H. Erectus split of ca. 2000 kya.
Admittedly, the evidence is thin, but there is pretty good circumstantial evidence to make the conclusion.
https://www.smithsonianmag.com/science-nature/fossils-some-last-homo-erectus-hint-end-long-lived-species-180973816/ Java Herectus 108ka Java Hsapiens 73ka Africa Hsapiens 300ka To me your claim is a little premature.
Also, no direct admixture from H. erectus, despite a decent possibility of them existing briefly at the same time given increasingly earlier evidence of Out of Africa (H. erectus existed through about 100 kya and the earliest Out of Africa dates are in that range), and given the lack of admixture likely co-existence of H. erectus and H. sapiens at the same time in Africa given earlier (the earliest H. sapiens in Africa are ca. 300 kya to 250 kya).
there is this
According to a study published in 2020, there are indications that 2% to 19% (or about ≃6.6 and ≃7.0%) of the DNA of four West African populations may have come from an unknown archaic hominin which split from the ancestor of humans and Neanderthals between 360 kya to 1.02 mya. However, the study also finds that at least part of this proposed archaic admixture is also present in Eurasians/non-Africans, and that the admixture event or events range from 0 to 124 ka B.P, which includes the period before the Out-of-Africa migration and prior to the African/Eurasian split (thus affecting in part the common ancestors of both Africans and Eurasians/non-Africans).
Arun Durvasula; Sriram Sankararaman (2020). "Recovering signals of ghost archaic introgression in African populations". Science Advances. 6 (7): eaax5097. Bibcode:2020SciA....6.5097D. doi:10.1126/sciadv.aax5097. PMC 7015685. PMID 32095519.
[1] Supplementary Materials for Recovering signals of ghost archaic introgression in African populations", section "S8.2" "We simulated data using the same priors in Section S5.2, but computed the spectrum for both YRI [West African Yoruba] and CEU [a population of European origin] . We found that the best fitting parameters were an archaic split time of 27,000 generations ago (95% HPD: 26,000-28,000), admixture fraction of 0.09 (95% HPD: 0.04-0.17), admixture time of 3,000 generations ago (95% HPD: 2,800-3,400), and an effective population size of 19,700 individuals (95% HPD: 19,300-20,200). We find that the lower bound of the admixture time is further back than the simulated split between CEU and YRI (2155 generations ago), providing some evidence in favor of a pre-Out-of-Africa event.
Durvasula, Arun; Sankararaman, Sriram (2020). "Recovering signals of ghost archaic introgression in African populations" (PDF). Science Advances. 6 (7): eaax5097. Bibcode:2020SciA....6.5097D. doi:10.1126/sciadv.aax5097. PMC 7015685. PMID 32095519.
an unknown archaic hominin which split from the ancestor of humans and Neanderthals between 360 kya to 1.02 mya.
= H. erectus
@neo
I recently saw a paper casting doubt on the African ghost population hypothesis, maybe at Razib's blog, although I'm not fully convinced of that view.
I have a backlog of anthro papers to blog.
@Andrew - "On what basis do you make that claim?"
http://dispatchesfromturtleisland.blogspot.com/2019/07/dilute-super-archaic-hominin-ancestry.html
newest theory
African multiregionalism
https://www.theatlantic.com/science/archive/2018/07/the-new-story-of-humanitys-origins/564779/
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