Lizard polymorphic throat colors are distinguishable by conspecifics and predators across variable light...

Area of Science:

• Evolutionary Biology
• Animal Behavior
• Sensory Ecology

Background:

• Color polymorphisms offer insights into phenotypic diversity.
• Understanding morph variation requires considering predator and conspecific visual perception.
• The Aegean wall lizard (Podarcis erhardii) displays distinct throat color morphs (orange, white, yellow).

Purpose of the Study:

• To investigate visual discrimination of P. erhardii throat color morphs by lizards and their predators (birds, snakes).
• To assess how different lighting conditions (daylight, forest shade) affect color perception.
• To explore the role of visual perception in maintaining color polymorphism.

Main Methods:

• Measured reflectance of P. erhardii throat color patches.
• Employed visual modeling to simulate perception by lizards, birds, and snakes.
• Analyzed chromatic and achromatic discrimination across varying illuminance contexts.

Main Results:

• Lizards and their predators can distinguish morphs chromatically in both daylight and shade.
• Lizards, but not predators, can distinguish morphs achromatically, except for white and yellow in shade.
• Predator discrimination is reduced in low lighting conditions.

Conclusions:

• P. erhardii morphs are least distinguishable by predators in low light.
• Reduced visual contrast may explain microhabitat partitioning among morphs.
• Visual ecology plays a crucial role in the evolution and maintenance of color polymorphisms.