Dangerous food: lacking venom and constriction, how do snake-like lizards (Lialis burtonis, Pygopodidae) subdue their lizard prey?
Version of Record online: 6 AUG 2007
Biological Journal of the Linnean Society
Volume 91, Issue 4, pages 719–727, August 2007
How to Cite
WALL, M. and SHINE, R. (2007), Dangerous food: lacking venom and constriction, how do snake-like lizards (Lialis burtonis, Pygopodidae) subdue their lizard prey?. Biological Journal of the Linnean Society, 91: 719–727. doi: 10.1111/j.1095-8312.2007.00835.x
- Issue online: 6 AUG 2007
- Version of Record online: 6 AUG 2007
- Received 22 November 2005; accepted for 20 November 2006
- foraging ecology;
- predator–prey interactions;
- squamate reptiles
Snakes are renowned for their ability to subdue and swallow large, often dangerous prey animals. Numerous adaptations, including constriction, venom, and a strike-and-release feeding strategy, help them avoid injury during predatory encounters. Burton’s legless lizard (Lialis burtonis Gray, Pygopodidae) has converged strongly on snakes. It is functionally limbless and feeds at infrequent intervals on relatively large prey items (other lizards) capable of inflicting a damaging bite. However, L. burtonis possesses neither venom glands, nor the ability to constrict prey. We investigated how L. burtonis subdues its prey without suffering serious retaliatory bites. Experiments showed that lizards modified their strike precision according to prey size; very large prey were always struck on the head or neck, preventing them from biting. In addition, L. burtonis delayed swallowing large lizards until they were incapacitated, whereas smaller prey were usually swallowed while still struggling. Lialis burtonis also displays morphological adaptations protecting it from prey retaliation. Its long snout prevents prey from biting, and it can retract its lidless eyes out of harm’s way while holding onto a food item. The present study further clarifies the remarkable convergence between snakes and L. burtonis, and highlights the importance of prey retaliatory potential in predator evolution. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 91, 719–727.