Orb weavers may spin poisonous webs

摘要

Orb weaver spiders are known for their big, beautiful wheel-shaped webs. These webs do more than just glue a spider's meal in place, a new study suggests - they may also swiftly paralyze their catch. Biochemical ecologist Mario Palma of Sao Paulo State University's Institute of Biosciences in Rio Claro, Brazil, has long suspected that these webs contain neurotoxins. The idea first came to him about 25 years ago, when he lived near a rice plantation. He often saw fresh prey, like bees or flies, in orb weaver webs. The hapless animals weren't just trapped - they convulsed and stuck out their tongues, as if they'd been poisoned. If he pulled the insects free, they struggled to walk or hold up their bodies. These odd behaviors struck Palma as the effects of neurotoxins.