|
Argiope aurantia : Living, Lusting, Loving, Wed, Dead
|
By rickyjames, Section News
Posted on Wed Jun 25, 2003 at 03:40:43 AM PST
|
|
And I thought mayflies had it rough. Now it's been reported that the male orb-weaving spider is genetically programmed to self-destruct during mating. Male spiders have two sex organs, called palps, which they insert into the female one after another. When the spider Argiope aurantia uses his second palp, he suffers an irreversible seizure, say Matthias Foellmer and Daphne Fairbairn of the University of California, Riverside. By dying while still joined to a female, his corpse forms a kind of chastity belt, according to the ecologists.
Update [2003-6-27 6:11:29 by rickyjames]:: Follow-up coverage in New Scientist: In 11 cases where competing males attempted to dislodge the dead mate, they only succeeded three times. And it was not for lack of trying, Foellmer told New Scientist: "The other males go beserk, bite into the legs and try to pull him off."
|
| John Whitfield of Nature reports this sad, sad tale of male spider destiny. "Immediately after [mating], [they] become motionless," says Foellmer. "Males show the typical dead posture, with legs folded under the body. Their hearts stop within 15 minutes."
The dead male's inflated palp remains wedged inside the female.. This prevents her from mating again and gives his sperm crucial minutes to fertilize her eggs. "The female cannot pull the male out for at least 15-25 minutes," says Foellmer. "Other males try hard to pull the dead male out, but often fail."
Like many spiders, the female eventually eats her deceased ex, but she is a bystander to his demise. Males probably put their whole selves into mating because finding a female is so onerous. Such extreme investment is common in spiders - others are so exhausted by sex that they stagger away and die; still more encourage the female to eat them, as it allows them to mate for longer.
But Argiope is, so far, the only animal found to be programmed to die during mating, says Foellmer. The report he co-authored is "Spontaneous male death during copulation in an orb-weaving spider," published by Proceedings of the Royal Society B.
If you've read this far, be sure to check out these other great Nature stories on spider follies:
Spider and fly swap roles
Silky doodles may confuse spiders' enemies
Spider scents attract prey
Eight-legged antics
Smaller spiders are better lovers
And to continue your research on wacky sex antics of animals, may I recommend...
|
 Bookmark this story with del.icio.us
 Digg this story
 Furl this item
 Have you Reddit?
|
