Genetics
The Mothers of Mankind
Evolutionary genetics suggests ancestral mothers domesticated us as a species.
Updated July 12, 2024
In the two previous posts I reported some remarkable recent research into domestication in general and into the seeming self-domestication of our own species in particular. But unlike our domestication of other species, our domestication of ourselves raises the issue of who was responsible. Surely, if there is domestication, there must be someone to carry it out? And including an entire species in the answer seems somewhat vague, to say the least!
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Dogs were probably the very first species to be domesticated, and the Freudian anthropologist Géza Róheim (1891-1953) claimed to have witnessed domestication in its original, nascent state. Róheim lived for many years among the Australian Aborigines and described how women who had just lost newborn babies (a distressingly common occurrence) would adopt dingo pups as pets and have them suck at their breasts to relieve painful persistent lactation. Perhaps not surprisingly, the resulting animals often became attached to their adoptive mothers for life and so were domesticated to that extent.
Again, another anthropological anecdote nicely illustrates the fact that in primal societies women are better than men at successfully raising domestic animals. Administrators in highland Papua New Guinea, intent on weaning warrior tribes away from war with the incentive of becoming cash crop pig farmers, found that piglets given to men to raise tended to get eaten, but that women (particularly older ones without young children) successfully tended them, and indeed kept them as household pets.
Of course, such anecdotes are hardly proof of anything; but they do provide a plausible precedent for a parallel picture of human females as the domesticators of their own species: which of course means males in the first instance. In the case of primates (monkeys, apes, and humans) generally:
Females provide social stability and group cohesion, are more affiliative and sustain the continuity of the group over successive generations. Females are the primary care givers with social rank of daughters, but not sons, being related to the matriline. Males, on the other hand, show greater mobility from the natal group, are more exploratory and their hierarchies are more overt, with high levels of sexual promiscuity and aggression.
Inducing docility is the major factor in domestication, and here it is worth pointing out that the contrary—impulsiveness—is a key feature which distinguishes male from female behaviour, particularly where violence, risk-taking, and anti-social behaviour are concerned, as I pointed out in a previous post.
In any event, development in domesticated animals is demonstrably much more in the female than male direction. Females are generally more neotenous (i.e., in retaining immature traits in adulthood): having smaller brains and jaws; flatter faces; less robust skeletons and musculature; and less or none of the sexual dimorphism that often characterizes adult males (such as horns, canine teeth, coxcombs, or coloration). Females are also generally more docile and domesticated than the majority of males, which are often castrated in captivity for precisely this reason.
But being female was only part of it. A second qualification of the domesticators of our own species was that they should be mothers—but not necessarily wives, as the following first-hand account suggests (at least if we take Australian Aborigines as representative of primal hunter-gatherers).
In 1947, King Alfred, an Australian Aborigine with six wives who was himself a five-time killer, was murdered by a bachelor in his mid-twenties:
"King Alfred led a big raid on my small mob. They came at night to steal women. They speared my brother Buddi and grabbed my young sister... All we could do was to run away in the dark… Buddi had been speared in the stomach and he died the next day. About three days later I … went to kill King Alfred and take his sister for payback… I sneaked up by the head of King Alfred and shifted the grass a bit so I could see him properly.Then I drove the spear hard into his stomach just below the chest. He gave one great shout and died. Percy was speared in the leg and again through the side as he ... ran away. I took King Alfred’s sister for my wife–today she is called Sally. We raped some of the women and went back to our own country." (p. 45)
To continue the forensic theme, and whatever their role as wives, ancestral mothers not only had "form" where dogs may have been concerned and their own children certainly were, they also had motive, means, and opportunity.
Hominin mothers had the motive by way of their equal relatedness to all their offspring thanks to the Mother's Baby—Father's? Maybe! principle. Such certainty of maternity gave mothers a genetic self-interest in domesticating their children to be docile, co-operative, and conforming members of their family—something which did not necessarily apply to fathers.
This was not only because fathers were male, but also because there is no necessary biological reason why children of the same mother should share the same father, and therefore no incentive for paternal genes of a woman's children to co-operate in the same way as shared maternal ones. On the contrary, we know that paternal genes are strongly expressed in the lower, limbic, or emotional brain in mice and that this is the part of the brain which undergoes reduction in domestication. Perhaps this explains why mothers have been found to be the chief moral socializers, with fathers tending to secondarily socialize children to be more self-orientated and independent.
But ancestral mothers also had the means by way of the maternally-active imprinted, X-chromosome, and perhaps mitochondrial genes which had evolved in mammals to be biased in favour of females. According to the imprinted brain theory, these are likely to be the genes implicated in mentalism (aka people/social/theory-of-mind skills), which you could argue was the prime psychological adaptation for human domestication because it is the key to being accepted by your fellow human beings. And according to the diametric model of mental illness, the fundamental pathology in psychosis is hyper-mentalism.
Indeed, in the previous post we saw that schizophrenia could be seen as a hyper-domesticated condition, and triplication of the X chromosome in so-called super females is associated with psychosis, with XXX subjects having brain imaging similar to that of schizophrenics. In Klinefelter’s syndrome, which features an extra X added to the normal male sex chromosomes (XXY), there is a 4 to 10 times heightened risk of psychosis, with more positive female-typical symptoms (auditory hallucinations and paranoia) and a female-typical age of onset along with neuro-anatomy similar to that seen in schizophrenia.
Mothers also had opportunity because, unlike the father in primal societies (and still predominantly today) mothers (and their kin) were the prime nurturers who could exploit the widened window of opportunity for socialization which domestication typically gives domesticators: weeks or months in domestic animals, but years in humans.
Furthermore, the same might perhaps have been even more true if primal mothers were prime non-nurturers of non-docile, defiant, or difficult-to-socialize offspring. Abortion, after all, whether natural or induced, is much more in the mother’s genetic self-interest than the father’s: her genes will predictably be present in all her offspring, including future ones; the father’s need not be, so his genetic interest coincides more closely with that of the foetus in being in a this-or-nothing situation (something which perhaps explains why abortion is a feminist demand, and resistance to it is associated with patriarchy).
Finally, the fact that (save for the hundred-odd genes on the Y chromosome) both sexes share their DNA means that ancestral mothers' domestication of their offspring would indeed have made them the mothers of mankind—in all senses of the term.
(With thanks to my friend and colleague, the late and much lamented David McKnight, who, had I been able to discuss this with him may well have told me as he so often did in relation to similar insights in the past, that the Aborigines knew this in their own way all along!)
References
McKnight, D., Of Marriage, Violence and Sorcery: The Quest for Power in Northern Queensland. Anthropology and Cultural History in Asia and the Indo-Pacific. 2005, Aldershot: Ashgate. 259.