What causes the arctic fox's color change from summer to winter?

The color change of the arctic fox from summer to winter is primarily due to the expression of certain genes that are influenced by temperature variations. As the seasons change, the arctic fox's hormonal and metabolic processes respond to the environmental cues, leading to changes in the pigmentation of its fur. This seasonal adaptation is a survival mechanism; the white winter coat provides camouflage in the snowy environment, while the brown or gray summer coat helps the fox blend in with the tundra landscape during the warmer months.

This genetic expression is an example of phenotypic plasticity, wherein the phenotype (observable characteristics) changes in response to environmental stimuli. Factors like seasonal temperature variations play a crucial role in triggering the specific genes responsible for fur color changes, highlighting a fascinating interaction between genetics and the environment.