Rapid evolution of mimicry following local model extinction

Area of Science:

• Evolutionary Biology
• Ecology
• Behavioral Ecology

Background:

• Batesian mimicry provides palatable species protection by resembling toxic species.
• Predators avoid toxic species, thus avoiding their mimics.

Purpose of the Study:

• To investigate the evolution of Batesian mimicry in kingsnakes after the local extinction of their coral snake model.
• To determine the direction and precision of mimicry evolution in the absence of the model.

Main Methods:

• Comparative analysis of mimicry precision in kingsnake populations.
• Examining kingsnakes from a region with recent coral snake extirpation versus a region where coral snakes remain.
• Assessing mimicry changes in a sympatric non-mimetic species for control.

Main Results:

• Kingsnakes in the region of coral snake extinction evolved more precise mimicry.
• No change in mimicry precision was observed in a non-mimetic species or in kingsnakes from areas with abundant coral snakes.
• The findings suggest continued evolution of mimicry even after model disappearance.

Conclusions:

• The historical fitness cost to predators of mistaking a toxic model drove the evolution of precise mimicry.
• This 'evolutionary momentum' can maintain or increase mimicry precision after model extinction, especially when few predator generations have passed.