I dislike stuff like that, because to me behaviour is something one controls using one’s will power. Saying something unfavourable is “caused” by one’s genes is a great way to excuse bad impulse control, and my inner Calvinist wants to tear her hair out in frustration. Not everything is as scientific as some people believe.
The fact that children raised in homes without a dad have sex earlier is down to their genes, say US researchers.
The study tested for genetic influences as well as factors such as poverty, educational opportunities and religion.
The more genes the children shared, the more similar their ages of first intercourse regardless of whether they had an absent father or not.
Rebecca adds: I think there’s something to this (and I also think that having a genetic predisposition to something – drinking, anger, unacceptable paraphilias – doesn’t give you a blank cheque to indulge, although it does mean you deserve extra credit for being disciplined.) J. Philippe Rushton, not by any means uncontroversial but not automatically wrong on that account, points out that animals and their reproductive strategies fall along a continuum, with frequency of reproduction increasing as the amount of effort put into parenting decreases. Humans, horses and elephants are at one end of the extreme; the vast majority of their pregnancies are singletons, gestational periods are long, and offspring require sustained and expensive care before they are autonomous. Rabbits and mice are at the other end for mammals, having large litters few of whom need to make it to adulthood for the genes to be passed on, and shorter gestational periods. Non-mammals trend even more strongly towards frequent reproduction and low investment parenting; think of the number of tadpoles produced by one pair of frogs.
Rushton suggests that humans show variation on this continuum by group. We would expect that a high frequency, low involvement approach would manifest biologically in greater frequencies of multiple births, slightly shorter gestation, and earlier sexual maturity. He gets people smoking out their ears by grouping different races along this continuum. But we can dispense with that dimension entirely and still consider a genetic connection here. It’s notable, though, that minorities with conservative social values and largely intact families seem to suffer vastly less from “racism” than other groups with particularly high out of wedlock births and their accompanying ills; if racism were indeed the causal factor, it’s puzzling that it harms some “non-whites” so much more than others.
Another, less inflammatory, approach is the “cads vs dads” theory. This holds that men in particular can ensure that their genes are passed on in one of two ways: by having relatively few children and focusing extensively on their nurturing to adulthood (dad), or by fathering multiple children and relying on the odds that some of them will make it to adulthood even with his dissipated involvement and resources (cad). What I would find really fascinating would be a look at whether sexual maturity comes earlier to children raised without fathers, since this is more a result of nature than first sexual activity which, being largely behavioural in a way that physical puberty isn’t, is a product of nurture.by