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Coat Color Changes in Arctic Foxes

APBIO-4LYYPT

Arctic foxes observed in their natural wild habitats develop white coats in the winter months. In the summer months, when they shed their winter coats the white fur is replaced by dark fur.

Captive arctic foxes kept in zoos located at more southerly latitudes tend not to develop white "winter" coats unless their zoo habitats are cooled to mimic arctic temperatures.

Which of the following is the MOST likely cause for the change in coat color observed in the wild fox populations?

A

Structural changes in the pigment molecules of the fur caused by cooler temperatures that cause the fur to look white.

B

A reduction of pigment deposition as the foxes change their eating habits from being mainly berry eaters in the summer to being mainly meat eating in the winter.

C

Repression of the transcription of genes for pigment production brought on by colder environmental temperatures.

D

The expression of genes for pigment production stimulated by exposure to sex pheromones produced by the opposite gender during the spring mating season.