Zoology comes from the Greek zoon, which means animal, and logos, which means study. Zoology is the science that study the animals as well as the relationships between them and the environment in which they live. Zoology also studies the structure of animals, which constitute their tissues, properties and cellular functions.
Approximately 2,000,000 species of animals are known, but some experts believe that in certain groups, only a small fraction of existing species is known.
Animal physiology is studied from anatomy and embryology. The genetics and evolutionary mechanisms of animals are studied through molecular biology, molecular genetics and evolutionary biology. Animal ecology studies its ecological behavior. In evolutionary biology, population genetics, heredity, variance, Mendelism and reproduction are considered. Other sciences study characteristics that are common to each species or group of animals.
Included in the study of animal morphology is the recognition of all types of extinct and current animals, and their distribution in time and space.
Zoology is subdivided into several branches, such as Mastozoology that studies mammals, Ichthyology which studies fish, Ornithology studies birds, and Ethology which studies the behavior of animals.
