Zoology (also known as animal science) is the branch of biology devoted to the study of animal life. It covers areas ranging from the structure of organisms to the subcellular unit of life. Some zoologists are interested in the biology of particular groups of animals. Others are concerned with the structure and function of animal bodies. Still others study how new animals are formed and how their characteristics are passed on from one generation to another. Zoologists study the interactions of animals with one another and their environments, as well as the significance of the behavior of animals.