Meeting Abstract
Death adders (genus Acanthophis) are ambush predators that entice prey within striking range by moving their tail tip in hypnotic undulations (caudal luring). This ambush hunting strategy makes death adders unique among Australian venomous snakes (Elapidae) and ecologically convergent with vipers and rattlesnakes (Viperidae). However, unlike viperid snakes that tend to stop caudal luring in adulthood, both juvenile and adult death adders caudal lure despite showing ontogenetic shifts in diet: juveniles tend to eat small frogs and lizards; adults eat large lizards, birds and mammals. To test whether caudal luring is retained in adults to lure new prey types (i.e. endotherms), we examined the hue, texture and shape of caudal lures in captive juvenile and adult A. antarcticus from South Australia. We found that once a snake reaches a certain mass, the caudal lure undergoes changes in dermal pigment colouration and epidermal microstructure, resulting in a different caudal lure morphology in adults. These results suggest that caudal luring is under selection to attract specific prey types into adulthood, which has implications for our understanding of how morphology relates to luring behaviour and how predators exploit sensory biases in prey.
