A recent simulation study took into account three factors:
While the historical impact of that long-ago conflict was discounted, the researchers included in their simulation three elements known to have a big effect on small populations.
These included the impacts of inbreeding, Allee effects (a biological phenomenon where a small population reduces the average fitness of individuals in the group), and stochasticity: random demographic fluctuations in births, deaths, and sex ratio, which end up putting smaller groups at a disadvantage in terms of overall survival.
According to the researchers, these factors alone – totally aside from any hypothetical clashes with other ancient humans for resources – were enough to result in Neanderthal extinction over the simulation timeframes of up to 10,000 years.
Peter Dockrill, “New Study Claims We Probably Didn’t Wipe Out The Neanderthals After All” at ScienceAlert
ScienceDaily puts it like this: “The population models show that inbreeding alone was unlikely to have led to extinction (this only occurred in the smallest model population). However, reproduction-related Allee effects where 25 percent or fewer Neanderthal females gave birth within a given year (as is common in extant hunter-gatherers) could have caused extinction in populations of up to 1,000 individuals. In conjunction with demographic fluctuations, Allee effects plus inbreeding could have caused extinction across all population sizes modelled within the 10,000 years allotted.”
But surely there’s also another factor. If current humans invaded Neanderthal territories, chances are, most of the advance group were young men. What happens when there are 100 guys (50 Neanderthal guys and fifty non-Neanderthal guys) and fifty Neanderthal girls? No matter what else happens, a great many of the children will only be part Neanderthal. And if more newcomers continue to arrive, the trend will probably continue until only a small percentage of the Western European genome is Neanderthal—no mass slaughter is required to make that happen.
The paper is open access.
See also: Claim: Many types of human were kayoed in the Sixth Great Extinction The trouble with these kinds of stories is, they write themselves. We don’t need data. If we like our history without much data, we should read epics instead of this stuff.
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Those Neanderthals were always too dumb to know how dumb we needed them to be By the way, seriously. was YOUR boss a Neanderthal too? 😉