How the Girl Evolved Fear of Spiders

Today’s Evolutionary Just-So Story is brought to you by New Scientist: “Girls Are Primed to Fear Spiders.”  Once upon a time, while cavemen were out hunting and gathering, the women back home had to learn to avoid dangerous animals.  David Rakison of Carnegie Mellon University put this all into evolutionary terms for the rest of us:

He attributes the difference to behavioural differences between men and women among our hunter-gatherer ancestors.  An aversion to spiders may help women avoid dangerous animals, but in men evolution seems to have favoured more risk-taking behaviour for successful hunting.
    It makes evolutionary sense to acquire spider fear at a certain age, rather than to be born with it, he adds.  “There is little reason for an infant to fear an object unless it can respond to it, for example by crawling away,” he says.

Rakison did not explain how a genetic mutation became fixed in the female of the species but was not expressed in the male.  Nor did New Scientist object to the ostensibly Lamarckian explanation.  Or was there some reasoned conspiracy that early men for millions of years all decided to mate with only the females who showed fear of spiders?  That wouldn’t make “evolutionary sense.”  Nevertheless, the article continued, psychiatric help can assist those women who have trouble with their evolutionary arachnophobia.

Remember the T-shirts labeled “Stupid” and “I’m with Stupid”?  One wonders who is more stupid; the accused idiot, or the idiot who keeps hanging out with him.  Rakison just told an incredibly stupid story, but New Scientist played “I’m With Stupid” and didn’t say a word about it.  They even heard him mention “evolutionary sense” without pointing out the oxymoron.  By playing along as if Stupid said nothing stupid, New Scientist wins Stupider Evolution Quote of the Week.