Instinct is the natural behavior of animals and humans, aimed at adaptation to specific conditions of life in the environment (life saving and preservation of the kind). Instincts emerged in the process of evolution of the species. When changing living conditions expediency of the instinct can be lost. Instincts always occur only when exposed to certain environmental factors on specific receptor education. The result is strictly fixed program behavior. Most clearly instincts are manifested in lower organized animals. The higher animals and human instincts acquire a large number of the conditioned reflex components that provide a more subtle adaptation of the body to the changing conditions of an environment (see Conditional reflexes). Cm. also Unconditioned reflexes.