Cockroaches on a blind date may trade life for the promise of sex

Could it be the scientific breakthrough of the century? After decades of trying, scientists have identified and isolated the chemical that gives female German cockroaches their sex appeal - offering humankind a chance of victory over perhaps its most indestructible foe.

Could it be the scientific breakthrough of the century? After decades of trying, scientists have identified and isolated the chemical that gives female German cockroaches their sex appeal - offering humankind a chance of victory over perhaps its most indestructible foe.

In varying sizes and colours, cockroaches are to be found in every corner of the planet, blamed for the spread of almost every pestilence known to man. The most widespread species is the German cockroach - half an inch long and light brown in colour, and famed for its speed.

Humans have tried to gas them and poison them with ingenious combinations of chemicals. Especially popular in the US are lethally baited sticky traps called "roach motels", sold under the slogan "They Check In but They Don't Check Out". But as anyone who has had a roach problem knows full well, nothing works for long. The creatures have been around for 200 million years, and are reputedly capable of emerging unscathed from nuclear armageddon.

But now they may be about to meet their match. According to the journal Science, US researchers have produced a synthetic version of the female cockroach's sex pheromone - the magic ingredient that makes male cockroaches drop everything in the interest of helping their ladies to produce some 350,000 offspring per breeding season. Coby Schal, professor of entomology at North Carolina State University and an author of the study, says the faintest whiff will have the most starving roach come running. "The male will choose the sex pheromone over food, even though he may die on the way." The study found that when a minuscule quantity of the artificial pheromone was placed in one branch of a forked plexiglass tube, 60 per cent of a sample of cockroaches chose that branch and made their way to the sample in less than 10 seconds.

For designers of coachroach traps, the substance is potentially the most most potent bait yet, capable of luring roaches by the millions to their doom. But there is one small problem. In the lab test, 40 per cent of male roaches failed to respond to the pheromones, for reasons unclear. It seems man's battle with the roach is not yet won.