New DNA evidence suggests that infectious diseases have been around a lot longer than we previously thought at it is also suggesting that humans coming out of Africa may have infected Neanderthals who likely did not have a natural immunity to the diseases. Although this did not cause Neanderthals to go extinct it certainly would have contributed to it.
When Cortez and his Spaniards invaded Mexico the Mexica (Aztecs) had no natural immunity to the diseases like smallpox that they carried with them. Thousands of Mexica died of smallpox and other diseases that Europeans had natural immunity to. The same scenario played out in the US and South America when Europeans arrived and native populations became infected causing thousands of deaths. So it is no stretch of the imagination to see how Homo sapiens coming out of Africa could have brought infectious diseases with them to which the Neanderthals had no natural immunity and resulted in their demise.
This new information comes from Dr Charlotte Houldcroft published in the American Journal of Physical Anthropology. She suggests that H. sapiens coming out of Africa would have been a “significant reservoir of tropical diseases.” She goes on to suggest that such disease infecting the Eurasian Neanderthals would have been catastrophic. This would have tipped the balance of their survival. She further suggests the scenario may not have played out like it did when Cortez or Columbus came to the Americas but I think she is likely wrong about that assumption. I think that it is HIGHLY likely that it did play out in the SAME pattern as that of Cortez and Columbus when they came to the Americas.
Finally some evidence and theory that makes sense as to what the fate of the Neanderthals was instead of the mythical theory that they just sort of disappeared into thin air!!!
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