Monday, May 12, 2008

Love in the afternoon

Oh, if only it were that simple. We human males must woo and coo and wash dishes and vacuum and buy roses and provide candlelight and wine and whisper "God, you look beautiful tonight" and who knows what else to entice our partners into bed. The male fruitfly need only sing. Well, not sing exactly. He vibrates one wing, just one, to make what one assumes is a pleading sort of noise. If the song is satisfactory, the female fly allows copulation.

Female fruitflies don't sing, which has long suggested that they lack the neural circuitry to produce the wing vibrations.

Now, in a clever series of experiments reported in the journal Cell -- involving photoactivation of neurons and the chopping off of heads -- researchers have shown that females have the same song circuitry as males, located in the thorax. They can sing too. But their brains tell them not to.

The difference in behavior has been traced to a dimorphic command center in the brain. Female fruitfly brains are different than male fruitfly brains.

As if that's telling us something we didn't already know.

Inhibition, the biologists call it. A cluster of neurons in the female's brain inhibits the wing-fluttering behavior. Male insect brains inhibit certain behaviors too. Some biologists believe the female praying mantis bites off her partner's head to improve his sexual performance. This seems a rather drastic way to overcome his inhibitions. Humans are more inclined to rely -- counterproductively, perhaps -- on alcohol.

Anyway, it's all rather complicated. The sexes will never understand each other, regardless of species. We have these packets of neurons all over our bodies urging us to do certain things, and other packets telling us not to. Someday biologists may figure it out, using brains scans, genomes, photoexcitation of neurons, and other techniques yet to come.

For myself, I'd just as soon not know what's going on at all those synaptic centers of excitation and inhibition. Everything I know about sex, I learned at the movies.