Journal of the Lepidopterists' Society 41(3). 1987. 141 - 144 PREDATION BY ANOLIS LIZARDS ON BATTUS PHILENOR RAISES QUESTIONS ABOUT BUTTERFLY MIMICRY SYSTEMS FRANCOIS J. ODENDAAL, MARK D. RAUSHER, BETTY BENREyl AND JUAN NUNEZ-FARFANl Zoology Department , Duke University, Durham, North Carolina 27703 ABSTRACT. Anolis lizards in Texas make supposedly distasteful and poisonous Battus philenor adults a component of their natural diet. The lizards appear to suffer no ill effects, and individual lizards will eat Battus more than once. We followed individual female butterflies searching for oviposition sites for 90 h and observed 4 instances of predation in the field. We supplemented these observations with field experiments and a laboratory study. Results raise questions about the general importance of lizard predation in the evolution of butterfly mimicry systems. Additional key words: Papilionidae, aristolochic acid, distasteful butterflies, pipevine swallowtail. Mimicry is widespread in nature, and studies of predation on but- terflies have been prominent in the development of ideas about apo- sematic coloration (Brower 1958, Brower et al. 1963, Rothschild et al. 1972). Most of these studies have involved examining the behavior of captive predators when offered palatable and distasteful butterflies. There is remarkably little information on predation of adult butterflies in nature, and published field observations deal almost exclusively with attacks of birds on butterflies (Fryer 1913, Rutowski 1978, Wourms & Wasserman 1985). Observations of natural predation by lizards are rare (Ehrlich & Ehrlich, 1982), yet "birds and lizards have long been con- sidered to be the major selective agents responsible for the extreme diversity of unpalatable and mimetic forms of butterflies in nature" (Boyden 1976). When wild Ameiva lizards in their natural habitat were fed live butterflies, they quickly became conditioned to avoid unpal- atable species (Boyden 1976). Ehrlich and Ehrlich (1982) observed iguanid lizards preying on tropical butterflies, and because different butterfly species seemed to be attacked differently, concluded that their observations supported the assumption that lizards are often strong selective agents in the evolution of butterfly color patterns and behavior. One classic study of mimicry in butterflies focused on the pipevine swallowtail and its mimics. The larvae feed on plants in the genus Aristolochia (Aristolochiaceae). The adults are distasteful to birds (Brower 1958), presumably because they sequester distasteful aristolochic acids and related alkaloids, as do other Aristolochia-feeding papilionids (Euwe et al. 1968, Rothschild et al. 1972). These substances are poisonous to , instituto de Biologia, Universidad Nacional Autonoma de Mexico. Apartado Postal 70-233. Mexi co 20, D.F.