Neuroethology is the evolutionary and comparative approach to the study of animal behavior and its underlying mechanistic control by the nervous system. This interdisciplinary branch of neuroscience endeavors to understand how the central nervous system translates biologically relevant information into natural behavior. Neuroethology is a multidisciplinary field composed of neurobiology (the study of sensory systems and the nervous system) and ethology (the study of behavior in natural conditions). A central theme of the field of neuroethology, delineating it from other branches of neuroscience, is the focus on natural behaviour, i.e. those behaviours generated through means of natural selection.