The acoustic environment and parent-offspring communication in birds

) ) Animals communicate using a range of signals, from whispered calls between mates to the elaborate displays of courting males. Explaining the structure and diversity of such signals has been a central problem in the study of animal communication. Studies on adult animals show that acoustic signals are often structured in ways that help transmit the signal through the environment and improve reception by receivers. ) ) Young animals also produce acoustic signals, as part of vigorous begging displays used to solicit food from parents. The intensity of these signals has puzzled evolutionary biologists because they appear to waste energy and make the young obvious to predators. Many studies have tried to explain why these begging signals appear so conspicuous, but few have examined the role the environment might play in explaining their structure. ) ) My students and I study parent-offspring communication in birds, with a focus on understanding how conspicuous begging signals may have evolved. In this proposal, we test the idea that selection for effective transmission and reception through the environment of the nest explains the structure of begging signals, particularly begging calls. Specifically, we examine how the acoustics of the nest, acoustic competition from nest mates and environmental noise together affect the types of signals given by young birds. ) ) Understanding how animals communicate is central to understanding all aspects of their social behaviour. Communication between parents and young is particularly important because it affects offspring growth and survival. Our work is the first to address fundamental questions about how the environment affects these important signals. It also examines how noise impacts parent-offspring communication, which is a growing problem for animals living in or near urban areas, where anthropogenic noise is increasing.