Substrate vibrations, induced in web, leaf, ground or water surfaces by nearby disturbances (such as prey, mate or predator movement), cause slight movements in a waiting spider's limbs. This high sensitivity to air-borne vibrations can alert the spider to the wing beats of an approaching moth or fly, or the presence of a wasp predator. These hairs are easily deflected and their 'ball and socket' basal hinge allows them to respond to air movements coming from any direction. Vibrations transmitted through air, substrate surfaces and even water can be sensed by spiders.Īir vibrations and currents are detected by slender, vertical hairs called trichobothria, usually found on the upper surface of the three outermost limb segments. Chemically sensitive, hollow-tipped hairs found at the ends of the limbs and on the mouthparts are the spider's tasting organs - those on the pedipalps are used to sense the chemicals associated with mate recognition.Īnother stimulus to which spiders are incredibly sensitive is vibration. Hinged, touch-sensitive hairs on the legs help the spider to move freely about its terrain and are important in interactions ranging from mating to prey capture. Connected at their bases to sensory nerves, they provide spiders with the sensory experience and feedback needed to survive and function in their world. These hair and pit sensillae are especially associated with the spider's limbs and mouthparts. With a few notable exceptions, their sense of the world is obtained through specialised sensory hairs and pit-like sense organs in the cuticle. However, most spiders have very poor eyesight and many are active during the dark night hours. Unlike us, spiders use their hairs (which are often greatly modified) to perform an amazing variety of tasks - for sensing their world, in courtship displays, for moving around, and in defence and prey capture. Spider hairs are part of the hard outer cuticle (the spider's 'skin').

Rack 2 furry science screen shots