Question

What are similarities and differences between migration in robins and a thick fat layer in polar bears as means of enhancing their survival?

Answer 1

Both are used to make the species an increased change of surviving the winter.

Explanation:

The robins migrating is a example of the species not physically changing with the environment so they must move to a place with warmer weather.
When the polar bear gets a thick fat layer, it benefits them because it helps the species retain heat which physically changes the animal with the environment.