Homology in the behavior of animals is sometimes used to indicate the degree of relatedness between groups. Suggest how behavior could be used in this way:

In other words, similarities in animals behaviors can sometimes show how closely related these two animals are. Why?

For the answer to the question above, If animals are related they share genes in common. The more genes they share on their DNA, the more alike they may be, like the rodents.

However, the behavior is caused not only by genes but by the environment plays an important part as well.