A Philippine group of people have the highest level of Denisovan ancestry

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.

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2021 by Austin Whittall © 

Human footsteps 21-23,000 years old in New Mexico

It has been some time since my last post, work and health issues have kept me busy with other less interesting matters, but hopefully I will find more time to keep on posting.

The paper published in Science magazine yesterday is really surprising (not for me, but for the orthodox viewpoint that is against an early date for the peopling of America).

The paper (Evidence of humans in North America during the Last Glacial Maximum by Matthew Bennet et al., 24 Sep 2021, Science Vol 373, Issue 6562 pp. 1528-1531 DOI: 10.1126/science.abg7586) reports dating ancient footprints from a New Mexico lake in White Sands National Park (WHSA).

The introduction and abstract tell us the following:

"Early footsteps in the Americas
Despite a plethora of archaeological research over the past century, the timing of human migration into the Americas is still far from resolved. In a study of exposed outcrops of Lake Otero in White Sands National Park in New Mexico, Bennett et al. reveal numerous human footprints dating to about 23,000 to 21,000 years ago. These finds indicate the presence of humans in North America for approximately two millennia during the Last Glacial Maximum south of the migratory barrier created by the ice sheets to the north. This timing coincided with a Northern Hemispheric abrupt warming event, Dansgaard-Oeschger event 2, which drew down lake levels and allowed humans and megafauna to walk on newly exposed surfaces, creating tracks that became preserved in the geologic record. —AMS
Abstract
Archaeologists and researchers in allied fields have long sought to understand human colonization of North America. Questions remain about when and how people migrated, where they originated, and how their arrival affected the established fauna and landscape. Here, we present evidence from excavated surfaces in White Sands National Park (New Mexico, United States), where multiple in situ human footprints are stratigraphically constrained and bracketed by seed layers that yield calibrated radiocarbon ages between ~23 and 21 thousand years ago. These findings confirm the presence of humans in North America during the Last Glacial Maximum, adding evidence to the antiquity of human colonization of the Americas and providing a temporal range extension for the coexistence of early inhabitants and Pleistocene megafauna."

The prints were dated using seeds of an aquatic plant found in the lake's sediment. This can't be argued away easily. These are human prints (and the paper adds that "The WHSA tracks, similar to the fossil tracks from Namibia, are flatter-footed than the modern samples, similar to what is commonly reported for habitually unshod individuals ... The WHSA footprints also have longer toe pads that we suggest are associated with slippage of the foot during locomotion."

It also explains why megafauna was becoming extinct even before humans arrived (humans arrived earlier than thought, and provoked these extinctions): "The overlap of humans and megafauna for at least two millennia during this time suggests that if people were hunting megafauna the practices were sustainable, at least initially. This also raises the possibility of a human role in poorly understood megafauna extinctions previously thought to predate their arrival and makes “early” sites in the Americas appear more plausible".

Photo of the prints, from the paper:

Tracks in the sand 21-23,000 years old.

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Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2021 by Austin Whittall ©