The NP [Neanderthal predation] theory is based on the three Darwinian mechanisms of evolution: natural selection, sexual selection, and artificial selection. Speaking of sexual selection, in one of the first chapters of Them and Us, Vendramini tells us:
Among the higher mammals—and this is particularly true of primates— it is usually the female that is proactive in selecting a mate. While males will mate with any female in oestrus, females are more discriminating. This would suggest that Skhul-Qafzeh females [our ancient hominid ancestors, represented above in the figure on the right (on the left, a Neanderthal)] used sexual selection as an evolutionary tool more than the males did. But, as we are about to see, the final mechanism of selecting anti-Neanderthal traits was wielded almost exclusively by males.
A little further on, he adds about artificial selection:
When Darwin coined the term natural selection, he meant that nature was doing ‘the selecting’—that the natural environment the organism lived in was a major determinant of which members lived and which died. In addition, Darwin described artificial selection: the way farmers and breeders intentionally select certain traits in domestic animals, which is a relatively benign form of artificial selection. However, the term also applies to the lethal form of selection—almost always applied by human males—as to who lives and who dies.
So the third way that anti-Neanderthal adaptations spread was by artificial selection—where coercion, ostracism, banishment and lethal violence by Skhul-Qafzehs gradually removed from the gene pool any individual who (for whatever reason) they considered too Neanderthaloid. NP theory holds that, throughout the Late Pleistocene, coalitionary groups of human males increasingly resorted to infanticide and homicide to eradicate Neanderthal-human hybrids, excessively hairy individuals, deviant neonates, or anyone who looked like a Neanderthal.
One of the most salient features of artificial selection is its speed. Unlike natural selection, which tends to create gradual change over thousands of generations, even benign forms of artificial selection can occur very quickly. A good example is the selective breeding experiments carried out in the 50s by the Russian geneticist Dmitri Belyaev to produce tame foxes. By selecting only the tamest foxes to breed, Belyaev and his team turned a colony of wild silver foxes into domestic pets within ten generations. The new animals were not only unafraid of humans, they often wagged their tails and licked their human caretakers in shows of affection. Even their physiology changed—the tame foxes had floppy ears, curled tails and spotted coats.
In eastern Spain, scrawled on a cave wall in red ochre, is one of the earliest known depictions of intergroup violence.
However, this rapid transformation of Belyaev’s foxes pales into insignificance compared to lethal and pernicious forms of human artificial selection—including genocide, ethnic cleansing, racial vilification [emphasis added], religious persecution and pogroms—that can exert a significant evolutionary impact almost overnight. The long history of such affronts and their ubiquitous application by disparate cultures separated by thousands of years supports the hypothesis that aggressive Skhul-Qafzeh males would have no compunction in eradicating anyone they felt was more them than us.
Historically, lethal violence and genocide have not been the business of women. Throughout human history, they have mostly been the preserve of males, and there is no reason to believe it was any different in the Late Pleistocene. Males claimed lethal violence as their own instrument of artificial selection. Groups of men decided what constituted a Neanderthaloid trait, and who felt like a Neanderthal. Men became the ultimate arbiters of who and what was acceptable. It was they who decided who lived and who died.
Given this, the use of artificial (or lethal) selection to remove anti-Neanderthaloid traits would be more prevalent on females, children and infants than on adult males. Sociological and anthropological evidence appears to support this more nuanced view.
Evolutionary biologist Ronald Fisher observes that when a trait conferring a survival advantage also becomes subject to sexual selection, it creates a positive feedback loop that leads to very rapid uptake of the trait. But we can now see that in the Levant it was not only natural selection and sexual selection that were working together to rid the population of hybridised individuals and Neanderthaloid characteristics. The process was also being logarithmically boosted by artificial selection—as coalitions of aggressive males banished or murdered their way towards the same common objective—towards a new kind of human that looked, sounded, smelt and behaved less like a Neanderthal. This blind, inexorable process would have made a substantial contribution to human evolution by identifying and quickly culling vestigial Neanderthal genes from the nascent human genome.
When the original Levantine population of Skhul-Qafzeh early humans was decimated by Neanderthal predation, the survivors became the nucleus of a new founding population of modern humans.
Although it may seem like a joke, this entry and others about how, through sexual and artificial selection, our ancestors eliminated all simian traits to produce the physiognomy of modern humans could be titled “How prehistoric men designed women” (see article here).
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N.B. You can read the first 35 pages of Vendramini’s book here.
