Special Prey, Special Webs: Fascinating Physics of Moth-Catching Spiders

Besides being scary, spiders are best known for their webs. Most spiders are not picky and attempt to catch any insect that happens to wander by. Yet surprisingly, moths present a unique challenge for spiders. When moths encounter a web, a powdery dust from their wings and bodies comes off, freeing the moth, and allowing it to escape. But there’s an exception to this rule: the Cyrtarachninae, a subfamily of spiders, which specialize in moth hunting using uniquely shaped webs. The most extreme of these are the bolas spiders. In this discussion, we will explore why moths are difficult to catch for normal spiders, show the variety of amazing adaptations made by Cyrtarachninae spiders, and view high-speed videos of predator-prey events. Enjoy small eats and non-alcoholic beverages provided courtesy of The Friends of Lyonia Environmental Center. This presentation is recommended for all ages.