The recent progress of acoustical techniques have made it possible for biologists to study the sounds produced by animals. These are of special interest since they can be correlated with specific forms of behavior. But parallel with these studies of what one might term “pseudo‐language” and the establishment of the “animal vocabulary,” an equally interesting aspect of the question is the study of the reactions of animals to sounds produced by man. My studies and those of my collaborators have led me to propose the terms “phonokinesis” and “phonotaxis” in order to classify, at least provisionally, the reactions of animals. These reactions which of course can appear with natural signals from the same animal species, are at times called forth by signals of another species. By an analytic procedure and for certain zoological groups such as the invertebrates and the lower vertebrates, we have succeeded in defining certain of the physical properties of sounds which provoke these reactions, permitting for example to attract or to drive away animals at a distance. The detailed study of different noises, used at times empirically for millenia by peoples close to nature, is extremely interesting and shows that certain types of hunting or fishing gear are actually generátors of acoustical signals to which certain species react. The forms of behavior in response to sound have more than theoretical interest; their deeper understanding may, a few years hence, lead to important applications in the protection of cultures.