During the warm temperatures of summer, the arctic fox produces enzymes that cause its fur to become reddish-brown. during the cold temperatures of winter, these enzymes do not function. as a result, the fox has a white coat that blends into the snowy background. what explains this change in color?
the genes of a fox are made of unstable dna
mutations can be caused by temperature extremes
random alteration of dna can occur on certain chromosomes
the expression of certain genes is affected by temperature

The return of the wolf to yellowstone national park will probably affect the bird population to some degree, not significantly. while wolves will hunt birds when necessary, they prefer to hunt larger prey. the bird population will most likely only be affected when hunting is scarce for the wolves. birds of prey will also probably not be affected as much as other birds who spend more time on the ground hunting for food as the tend to spend more time in the air or in trees since they do not need to stay on the ground for long due to the nature of the way they hunt.