Variation in predator response to short-wavelength warning coloration

Area of Science:

• * Ecology and Evolutionary Biology
• * Animal Behavior
• * Sensory Ecology

Background:

• * Warning coloration, often red or orange, deters predators from attacking unpalatable prey.
• * Blue, a short-wavelength color, is less common but functions as a primary defense in some species.
• * The diversity of warning colors may be maintained by differing predator responses to visual signals.

Purpose of the Study:

• * To test the hypothesis that interspecific variation in predator responses maintains warning color diversity.
• * To investigate innate avoidance and learning responses of different galliform birds to blue and orange prey.

Main Methods:

• * Tested Gambel's quail and two domestic chicken breeds (Plymouth Rocks, Cochin Bantams).
• * Measured responses to artificial prey colored blue (iridescent), orange, and orange-and-blue.
• * Assessed innate avoidance (first encounter) and associative learning speed.

Main Results:

• * Cochin Bantams showed innate avoidance of blue prey; Gambel's quail attacked blue prey readily.
• * Plymouth Rocks exhibited no innate aversion and attacked most prey items quickly.
• * Cochin Bantams and Gambel's quail learned to associate orange and orange-and-blue prey faster than blue prey.

Conclusions:

• * Interspecific variation in predator responses to warning colors was observed.
• * Predator perception differences, particularly to blue coloration, can contribute to the evolution and maintenance of warning signal diversity.
• * The findings support the hypothesis linking predator response variation to the spectrum of warning colors in nature.