Zoopsychologist, Dutch ethologist and ornithologist, one of the founders of ethology, the science of animal behavior. Scientific activity:
1) The main area of research is the behavior of animals in natural conditions.
2) Together with Konrad Lorenz and Karl von Frisch, he created the doctrine of the instinctive behavior of animals and its development in onto- and phylogeny.
3) He studied the role of stimuli in the group behavior of animals (bees, fish, seagulls), selective response to environmental factors, the relationship between acquired and innate behavioral components, the evolution of behavior and adaptive functions.
4) He laid the foundations of an experimental program of ethology and, on the basis of the Lorentz model of the behavioral act, created a hierarchical model of behavior.