Polarization sensitivity in reptiles

Abstract

Somewhat questionable evidence in support of reptilian polarization sensitivity (PS) has come from field and laboratory observations on the behaviour of a few species of marine and freshwater turtles. More convincing are conclusions based on PS-aided orientation in the lizards Uma notata, Tiliqua rugosa and Podarcis sicula. It is suggested that submersed hunters like, for instance, sea snakes ought to be included in examinations for PS since contrast enhancement by PS under water could bestow some benefits to them during food procurement. Courtship displays in certain species of lizards could also contain signals for which the presence of PS would be advantageous, but as yet polarization signals have not been demonstrated in any species. Results based on electrophysiological recordings to demonstrate PS in photoreceptors of the lateral eyes or pineal organs are scant and a connection between PS and magnetoreception is regarded as likely.