MEYERS, J.J.; HERREL, A.; Northern Arizona University; University of Antwerp: The thorny devil’s furious flick: prey capture strategies of ant specialized lizards

It has been suggested that lizards exhibit relatively little phenotypic specialization with regard to the feeding system. Although numerous lizard species appear to restrict their diet to specific prey, relative few studies have documented morphological or behavioural specialization to prey preferences. Here we describe the feeding strategies of two ant specialized lizards, the Australian thorny devil (Moloch horridus) and the desert horned lizard (Phrynosoma platyrhinos) in comparison to a dietary generalist, the bearded dragon (Pogona vitticeps). Animals were filmed feeding on ant prey and kinematic variables were calculated from digitized sequences. Statistical analysis of kinematic events revealed significant species differences. In general, M. horridus is quicker at capturing prey, with more rapid tongue protraction and an overall shorter gape cycle than both P. vitticeps or P. platyrhinos. However, with regards to prey processing M. horridus and P. platyrhinos are more similar to each other than to P. vitticeps. While the later species processes the prey extensively before swallowing the former species swallow the prey directly, significantly reducing the duration of the feeding event. Our results indicate that while the two ant species share some similarities (prey processing), M. horridus differs strongly from both species. These results are surprising considering M. horridus and P. vitticeps are more closely related to each other than they are to P. platyrhinos. While the lack of prey processing appears to be convergent behaviour of ant specialists the extremely rapid prey capture sequence is unique to M. horridus.