Arachnophobia

It's going to rain.

I knew it before the weatherman told me.

Because I trod on a spider.  I killed it.  Deliberately.

Though not a huge example -- like the 25mm Australian mouse-spider pictured above, which would have had me screaming for the trees -- I did not fancy the thought of it scuttling over my face while I slept.  Or running up my arm when I reached for something in a cupboard.  It is not that I am scared of spiders.  Not really.  After all, I like Alsatian dogs, and they are hairy fellows with long legs, too.

This morning while reading the DomPost I found that I did not have to feel ashamed of having killed the spider.  Apparently, arachnophobia is embedded in my genes.

Joshua New, a researcher at Columbia University in New York, has found that fear of spiders is a survival instinct. "A number of spider species with potent, vertebrate-specific venoms populated Africa long before hominids," he says.  And, for tens of millions of years, the two groups co-existed.  Sort of. Because one kept well out of the way of the other.

Our human ancestors in Africa were dead scared of spiders -- not because their venom was fatal, which it usually isn't, but because it incapacitated them for days, which meant they were easy fodder for any predator in the neighborhood.  And we still bear the vestiges of that very reasonable fear.  To test this, New and his colleague, Tamsin German, asked 252 people to study computer screens carrying abstract shapes, and to tell them what they spied lurking in the patterns. Of the shapes intended to produce disgust or fear, spiders were picked out the most quickly.

Vanessa LoBue, a researcher at Rutgers in New Jersey, has found with a similar test that even three-year-olds would spot spiders first among pictures of other threatening things, such as fungi and cockroaches.  

The human psyche is funny, though.  The story reminded me of an exhibit in the Australian Museum in Sydney, New South Wales, which is a big table where the top is a moving image of rippling water.  It is so well done that the viewer is drawn to touching at -- at which an Aussie nasty like a crocodile or snake comes rearing out of the "water," or a "spider" (uncannily like the one above) darts at your arm.  You can locate the exhibit by the sounds of delighted screaming.  People -- especially kids -- love being scared.  They approach that table time after time .. after time.