Differential detectability of polymorphic warning signals under varying light environments.

Area of Science:

• Ecology
• Evolutionary Biology
• Animal Behavior

Background:

• Aposematic species exhibit striking color-pattern variation, which is paradoxical given predator selection favors signal uniformity.
• Mechanisms maintaining this variation are poorly understood, with hypotheses including drift, gene flow, and adaptive processes like differential detectability.

Purpose of the Study:

• To investigate if differential detectability among warning signal morphs maintains polymorphisms in aposematic species.
• To test the role of light environment and predator experience in the detectability of different aposematic morphs.

Main Methods:

• Field experiments using wax models (aposematic vs. cryptic) to assess predator attack rates.
• Testing detectability of different aposematic morphs by human observers under varying light conditions.

Main Results:

• Cryptic models were attacked more than aposematic models.
• No significant difference in bird attack rates among different aposematic morphs was observed.
• Detectability of aposematic morphs varied based on predator experience and light environment.

Conclusions:

• Differential detectability, influenced by light conditions and predator experience, may maintain warning signal polymorphisms.
• The light environment is crucial for initial predator encounters and should be considered in future predation studies.