The selective advantage of crypsis in mice

Area of Science:

• Evolutionary Biology
• Ecology
• Animal Behavior

Background:

• The light coloration of Florida's coastal dune mice is a classic example of adaptation.
• The selective advantage of crypsis (camouflage) in these mice has not been empirically tested in natural settings.

Purpose of the Study:

• To directly test and quantify the selective advantage of crypsis in Peromyscus mice.
• To investigate the role of visual predators in shaping rodent coat coloration.

Main Methods:

• Utilized plasticine models of light and dark colored mice.
• Deployed models on sandy dune habitats to simulate natural predation scenarios.
• Quantified predation rates based on model coloration and background matching.

Main Results:

• Demonstrated a significant selective advantage for mouse models that matched their local background substrate.
• Found evidence of stabilizing selection maintaining optimal coloration within a habitat.
• Models deviating in color (lighter or darker) from the local environment experienced higher predation.

Conclusions:

• Visual hunting predators strongly influence the coat color patterns of Peromyscus mice.
• Selection for camouflage provides a mechanism for the observed color variation across mouse populations.
• This study provides empirical support for long-standing hypotheses on adaptive coloration.