 Ethology. Ethology is the scientific and objective study of animal behavior, usually with a focus on behavior under natural conditions, and viewing behavior as an evolutionarily adaptive trait. Behaviorism is a term that also describes the scientific and objective study of animal behavior, usually referring to measured responses to stimuli or trained behavioral responses in a laboratory context, without a particular emphasis on evolutionary adaptivity. Many naturalists have studied aspects of animal behavior throughout history. Ethology has its scientific roots in the work of Charles Darwin and of American and German ornithologists of the late 19th and early 20th century, including Charles O. Whitman, Oscar Heinrichs, and Willis Craig. The modern discipline of ethology is generally considered to have begun during the 1930s with the work of Dutch biologist Nicolaud Timbergen and by Austrian biologists Conrad Lorenz and Carl von Frisch, joint awardees of the 1973 Nobel Prize in Physiology or Medicine. Ethology is a combination of laboratory and field science, with a strong relation to some other disciplines such as neuroanatomy, ecology, and evolutionary biology. Ethologists are typically interested in a behavioral process rather than in a particular animal group for, and often study one type of behavior, such as aggression, in a number of unrelated animals. Ethology is a rapidly growing field. Since the dawn of the 21st century, many aspects of animal communication, emotions, culture, learning and sexuality that the scientific community long thought it understood have been reexamined, and new conclusions reached. New fields, such as neurophology, have developed. Understanding ethology or animal behavior can be important in animal training. Considering the natural behaviors of different species or breeds enables the trainer to select the individual's best suited to perform the required task. It also enables the trainer to encourage the performance of naturally occurring behaviors and also the discontinuance of undesirable behaviors.