Bioacoustics: the science of listening to animals — Animal vocalizations

Bioacoustics is a branch of science derived from ethology*. Although people have always been interested in the sounds produced by animals, it was a Slovenian biologist, Ivan Regen, who in the 1920s gave birth to bioacoustics as a genuine scientific discipline. This biologist became interested in the stridulations produced by different species of Orthoptera* (locusts and grasshoppers), which he recorded and then played back to individuals to observe their responses. It was the development of tools and methods for recording, analyzing and processing acoustic signals that led to the evolution of research in the field of bioacoustics. In 1945, the invention by the Bell laboratory of the sonagraph made it possible to visualize the three fundamental parameters of sound: time, frequency and intensity. In 1951, Swiss engineer Stefan Kudelski built a small, energy-independent tape recorder that revolutionized recording in natural environments. In the 1950s and 60s, technical advances in acoustic analysis and synthesis made it possible to study animal vocalizations in detail. Bioacoustics, as a field of research, developed first in English-speaking countries, mainly at Cambridge University in England and the Cornell Lab. of Ornithology in the USA... then in Europe. A French laboratory, under the aegis of René-Guy Busnel (director of the animal acoustics laboratory at EPHE and the acoustic physiology laboratory at INRA, Jouy-en-Josas), launched bioacoustics in France as early as 1965, and quickly gained international renown. The first animal models studied by bioacousticians were Orthoptera, birds and cetaceans. Today, it is estimated that over a hundred laboratories worldwide are working in this field. Research involving physiology, neurophysiology and domestic animals is mainly carried out in the laboratory, while more ethological and ecological research is carried out in the field with wild animals.