Question

1) Describe the experiment that tests the adaptive advantage of light vs. dark fur color in Peromyscus polionotus. State the hypothesis correctly, describe the experiment, explain the results, and state the conclusion.

Answer 1

a type of deer mouse, Peromyscus polionotus shows many variation in coat colours over a short geographic variation. One type is 'oldfield mice' which lives in abandoned agricultural fields with dark soils. they have dark brown dorsal coats, a light grey belly, and a sharply bi-colored tail. Another type is beach mice, these live in coastal sand, and have light coloured fur. The hypothesis about their coat color is, for the survival, they need to blend in their habitat environment so that they can save them from predators. That is why their fur color is according to their environment. One experiment was done to prove this hypothesis.

scientists produced one single type of mice. and they spray-painted them. half population dark and half population light color. Therefore, any differences in survival would be due only to color differences. Then they we set out the light and dark models (same no. of dark and light mice) at beach and at mainland also. On the next day, they recorded which models showed evidence of predation. Some body part was missing, some mice were missing. All the data were collected.

After the data collection, the main fact observed is : camouflaging color decreases predation. light colored mice had higher predation rate at mainland, and dark colored mice had high predation rate at beach. Light colored mice in beach and dark colored mice in mainland have a higher survival rate.

so from this we can conclude that camouflaging color has a large effect on survival in these mice.