Final thoughts on understanding animal vocalizations in the 21st century

Abstract Vocalizations are an important means for communication within and between all kinds of species. The previous chapters have shown that across species, vocalizations and forms of communications are unique to a given species, from insects to humans. However, there are commonalities in the neuroendocrine mechanisms governing such behavioral responses. Our ability to detect and understand such vocalizations continues to advance. Machine-learning approaches that detect, analyze, and eventually interpret various patterns will assuredly even further our ability and our comprehension as to what vocalizations across ranging taxa mean, identify potential commonalities based on pattern recognition, and even increase our understanding as to the mechanisms regulating varying forms of communication. This approach may even make us rethink how we join and split species when grouping them in evolutionary trees. Sadly, the fact that many of these forms of communication are regulated by steroid and nonsteroid hormones also makes them vulnerable to chemicals that can mimic such hormones, endocrine-disrupting chemicals. Those anthropogenic chemicals were shown to be able to alter critical features of vocalizations in several species or even cease the acoustic signals entirely, which potentially can result in population effects that may affect the whole ecosystem dynamics. It is the hope that by better understanding the normal regulatory mechanisms and disruptions caused by endocrine-disrupting chemical, it might serve as an impetus for countries to ban such chemicals to avoid a “Silent Spring.”