Venom Marinade

Certain spiders evolved a bizarre alternative to biting

- Gennaro Tomma

YOU DON'T ALWAYS NEED a book or movie for a good horror story. Sometimes, if you dare look closely enough, you can find one in your own backyard.

Researchers have just confirmed the inner workings of a brutal food-prep technique some spiders use, wrapping their web-snagged prey tightly in silk strands, then puking up toxic digestive fluids to soak the entire package to marinate their meal alive.

Spiders from the Uloboridae family, usually just a few millimeters long, have puzzled scientists because they seemed to lack venom-a substance that is widespread among spiders and "really linked to their evolutionary success," says Alex Winsor, a neuroethologist at the University of Massachusetts Amherst who wasn't involved in the new research.