Symposium: Insect Behavioral Ecology--'89: The Evolution of Multi Anti-Predator Characteristics as Illustrated by Tiger Beetles (Coleoptera: Cicindelidae)

Abstract

Tiger beetles as a family show a broad spectrum of morphological, behavioral and physiological mechanisms by which their enemies are deterred. This phenomenon of multiple anti-predator mechanisms is also evident within species and individuals. Although multiple anti-predator mechanisms have been widely recognized among most if not all insects groups, general models and broad theoretical studies of predator-prey interactions have largely ignored this confounding pattern. Based on experiments and observations of tiger beetles, six theories are presented that explain the evolution of multiple anti-predator characters: 1) several characters must operate in concert to minimize predation, 2) each anti-predator character is largely or uniquely targeted against one of several distinct foraging phases used by the predator, 3) increasingly potent lines of defense may be used as a predator overcomes the primary ones, 4) separate anti-predator characters are directed at each of several different types of predator, 5) an individual prey is the result of a phylogenetic or ontogenetic accumulation of anti-predator characters, and 6) competing or counterselective forces may override or supplement the effectiveness of some anti-predator characters.