Animals may be losing their ability to display adaptive camouflage because of changing environmental conditions. Snowshoe hares, ermines, caribou and arctic foxes all change colour from darker to lighter colours during winter, in order to blend into snow-covered landscapes.

How do arctic hares turn white in winter?

Several species of hares—including the Arctic hare (Lepus arcticus), the mountain hare (L. timidus), and the snowshoe hare (L. americanus)—turn from brown or grayish to white in the winter. The color change is thought to be at least partially linked to photoperiod—that is, the amount of light received during the day.

What causes hares to change colour?

“Like other seasonal traits, the autumn molt in snowshoe hares is triggered by changes in day length,” Good said. “But the color of their winter coat is determined by genetic variation that has been shaped by evolution to match the local presence or absence of snow.” … The genetic discovery came with a surprising twist.