Defense Spider

threat display sydney funnel-web spider (atrax robustus).

there strong evidence spiders coloration camouflage helps them evade major predators, birds , parasitic wasps, both of have color vision. many spider species colored merge common backgrounds, , have disruptive coloration, stripes , blotches break outlines. in few species, such hawaiian happy-face spider, theridion grallator, several coloration schemes present in ratio appears remain constant, , may make more difficult predators recognize species. spiders insufficiently dangerous or unpleasant-tasting warning coloration offer benefit. however, few species powerful venoms, large jaws or irritant hairs have patches of warning colors, , actively display these colors when threatened.

many of family theraphosidae, includes tarantulas , baboon spiders, have urticating hairs on abdomens , use legs flick them @ attackers. these hairs fine setae (bristles) fragile bases , row of barbs on tip. barbs cause intense irritation there no evidence carry kind of venom. few defend against wasps including networks of robust threads in webs, giving spider time flee while wasps struggling obstacles. golden wheeling spider, carparachne aureoflava, of namibian desert escapes parasitic wasps flipping onto side , cartwheeling down sand dunes.