Air Date: Week of December 28, 2001

Living on Earth’s Maggie Villiger reports on the discovery that male funnel-web spiders release a knockout pheromone so they can safely mate with females.

Transcript

CURWOOD: Coming up, a new bio-engineered rice might save millions from malnutrition. But first this page from the Animal Notebook with Maggie Villiger.

VILLIGER: If you think your love life is challenging, you might find some comfort by taking a close look at the courting rituals of the funnel web spider. Males in this aggressive species are sometimes eaten by their mates before, during, or soon after their eight to ten hour intercourse session. To ward off the sexual cannibalism, the guys have come up with a defense. They lull females into unconsciousness so they can mate without becoming dinner. Until recently, observers thought the males' elaborate courting dance somehow intoxicated females. But now, biologists have discovered proof that the spider Romeos are actually slipping a Mickey to their Juliets. When scientists ground up dead male funnel web spiders and wafted the extract near live spiders, almost three quarters of females were, literally, knocked out. Surprisingly, males also succumb to the potion. They must take very careful aim when releasing this chemical so they don't knock themselves out cold. Scientists are working on identifying this knock-out pheromone. It's unknown whether or not humans possess a similar reception pathway.
That's this week's Animal Note, I'm Maggie Villiger.

CURWOOD: And you're listening to Living On Earth.

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