Question

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?

Answer 1

Similarities in behavior can demonstrate the closeness between two species. They could have shared a common ancestor or faced the same evolutionary pressures which resulted in development of similar traits. For ex: human and chimpanzees share 99% of their DNA and they also share a lot of behavioral traits. Like humans, chimpanzees can also show various personality types like extrovert, introvert etc. Chimpanzee babies also use hand gestures to communicate like human babies. These shared behavior characteristics show that humans and chimpanzees are closely related to each other.

Answer 2

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.