Of tongues and noses: chemoreception in lizards and snakes.

Lizards and snakes inhabit a world so richly textured in chemical information that, as primates, we can only imagine it. Subtle nuances of chemical shading underline nearly every fundamental activity of their lives, from finding foot to finding mates. Recent work examines the nature of these chemical messages, mechanisms for their perception, the interplay of the chemical senses in the sociobiology of the group, and patterns of chemosensory evolution. Emerging is a new sense of lizard and snake behavioral complexity that belies the common notion of these animals as simple automata and points to a surprising capacity for plasticity and learning.