Another recent publication that caught my eye refers to Denisovans (Philippine Ayta possess the highest level of Denisovan ancestry in the world, by Maximilian Larena et al, August 12, 2021. Cuurent Biology. DOI:https://doi.org/10.1016/j.cub.2021.07.022).
The paper tells us:
"Highlights:... Ayta Magbukon display ∼30%–40% greater Denisovan ancestry than Australopapuans. The model is explained by a distinct admixture event into Negritos from Denisovans. Prior to modern humans, Islander Denisovans may have been present in the Philippines
Summary
... We show that Ayta Magbukon possess the highest level of Denisovan ancestry in the world—∼30%–40% greater than that of Australians and Papuans—consistent with an independent admixture event into Negritos from Denisovans. Together with the recently described Homo luzonensis, we suggest that there were multiple archaic species that inhabited the Philippines prior to the arrival of modern humans and that these archaic groups may have been genetically related. Altogether, our findings unveil a complex intertwined history of modern and archaic humans in the Asia-Pacific region, where distinct Islander Denisovan populations differentially admixed with incoming Australasians across multiple locations and at various points in time."
The paper argues that "The significantly higher level of Denisovan ancestry in Ayta Magbukon relative to Papuans highlights the possibility of an independent Denisovan introgression event in the Philippines among Negritos that is different from the Denisovan introgression event into the ancestors of Australopapuans. This observation is consistent with recent studies suggesting multiple pulses of Denisovan introgression into humans, that Denisovans were probably widespread throughout ISEA, and that Ayta Negritos were likely to have experienced a second Denisovan introgression event."
Furthermore, the Denisovans had split into different groups in the region and admixed separately with Papuans and Aytas: "our simulations provide support for the presence of two separate Denisovan lineages that independently introgressed into the ancestors of Ayta Negritos and Papuans, likely occurring around the same time after the Negrito-Papuan divergence 53 kya (95% CI: 41–64 kya). Upon entry of the first modern human migrants into Sunda and Sahul (ancestors of Negritos and Australopapuans), these ancestral Australasian groups likely experienced admixture with deeply divergent Denisovan-related populations scattered all throughout the ISEA and the Oceania region."
It also has an interesting suggestion regarding the different archaic hominins in the region (but it does not mention H. erectus): "Additionally, the physical evidence for a previously undescribed hominin in Luzon 67 kya, where present-day Negritos reside, combined with the genetic evidence presented here, raises the possibility that the suggested Homo luzonensis and Denisovans were likely genetically related, either as distinct forms or possibly belonging to the same group residing on the islands. Furthermore, it is not entirely impossible that the recently identified new species of archaic hominins in the Indonesian island of Flores, the Homo floresiensis,38 may also be related to Denisovans. Hence, the presence of multiple archaic human remains in the region, together with the genomic evidence presented here and elsewhere, raises the possibility that the Denisovans comprised deeply structured populations with considerable genetic and phenotypic diversity,"
Let's hope that we can soon identify the links between Denisovans and these other hominins.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2021 by Austin Whittall ©
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