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Angela
12-04-16, 18:17
These papers on Neanderthals are just pouring out.

This is from Cambridge, and like a lot of their papers they're behind a pay wall.
http://onlinelibrary.wiley.com/doi/10.1002/ajpa.22985/abstract

However, here is the abstract:

"High quality Altai Neanderthal and Denisovan genomes are revealing which regions of archaic hominin DNA have persisted in the modern human genome. A number of these regions are associated with response to infection and immunity, with a suggestion that derived Neanderthal alleles found in modern Europeans and East Asians may be associated with autoimmunity. As such Neanderthal genomes are an independent line of evidence of which infectious diseases Neanderthals were genetically adapted to. Sympathetically, human genome adaptive introgression is an independent line of evidence of which infectious diseases were important for AMH coming in to Eurasia and interacting with Neanderthals. The Neanderthals and Denisovans present interesting cases of hominin hunter-gatherers adapted to a Eurasian rather than African infectious disease package. Independent sources of DNA-based evidence allow a re-evaluation of the first epidemiologic transition and how infectious disease affected Pleistocene hominins. By combining skeletal, archaeological and genetic evidence from modern humans and extinct Eurasian hominins, we question whether the first epidemiologic transition in Eurasia featured a new package of infectious diseases or a change in the impact of existing pathogens. Coupled with pathogen genomics, this approach supports the view that many infectious diseases are pre-Neolithic, and the list continues to expand. The transfer of pathogens between hominin populations, including the expansion of pathogens from Africa, may also have played a role in the extinction of the Neanderthals and offers an important mechanism to understand hominin–hominin interactions well back beyond the current limits for aDNA extraction from fossils alone. Am J Phys Anthropol, 2016. © 2016 Wiley Periodicals, Inc.

These are some comments made by the lead author:

"Dr Charlotte Houldcroft, from Cambridge's Division of Biological Anthropology, says that many of the infections likely to have passed from humans to Neanderthals -- such as tapeworm, tuberculosis, stomach ulcers and types of herpes -- are chronic diseases that would have weakened the hunter-gathering Neanderthals, making them less fit and able to find food, which could have catalysed extinction of the species."

"However, it is unlikely to have been similar to Columbus bringing disease into America and decimating native populations. It's more likely that small bands of Neanderthals each had their own infection disasters, weakening the group and tipping the balance against survival," says Houldcroft."

It's difficult to say anything definitive since I can't find a copy of the actual paper, but this seems like a lot of conjecture.

The following is interesting, however.

"The longstanding view of infectious disease is that it exploded with the dawning of agriculture some 8,000 years ago, as increasingly dense and sedentary human populations coexisted with livestock, creating a perfect storm for disease to spread. The researchers say the latest evidence suggests disease had a much longer "burn in period" that pre-dates agriculture.In fact, they say that many diseases traditionally thought to be 'zoonoses', transferred from herd animals into humans, such as tuberculosis, were actually transmitted into the livestock by humans in the first place.
"We are beginning to see evidence that environmental bacteria were the likely ancestors of many pathogens that caused disease during the advent of agriculture, and that they initially passed from humans into their animals," says Houldcroft."

https://www.sciencedaily.com/releases/2016/04/160411082330.htm

Maleth
12-04-16, 19:06
Considering how seriously sparsely populated Neanderthals were (and in breeding was very common) and the rapid (in comparison) expansion of modern humans, the notion is not far fetched. Disease could have been easily a major cause but maybe not the only one.

laetoli
14-04-16, 14:09
Just so story