Zoology is the study of animals. It can be sub-divided into many disciplines, such as ornithology, the study of birds; primatology, the study of primates; ichthyology, the study of fish and entomology, the study of insects, etc. It gives us an in-depth knowledge to understand wildlife, animals, the environment and ourselves. It studies the way animals interact with surrounding organisms and environment. Aristotle was the first scientist to have described living things in-depth and studied about animals systematically.