Parrots are renowned in captivity for their vocal flexibility, and although studies of avian vocal learning focus largely on songbirds, there is some evidence that the majority of parrots may be more vocally flexible than many members of the songbird order. In addition, unlike the majority of most temperate songbirds, both male and female parrots produced learned vocalizations and often share a repertoire of calls, although anecdotal evidence from pet owners suggests that males may be the more vocally flexible sex. However, most of what we know about parrot vocal flexibility and sex differences in parrot communication comes from anecdotal evidence and very limited lab studies that have difficulty mimicking natural parrot social conditions. Thus, the purpose of this work was to investigate how wild parrots are using vocal flexibility during interactions with conspecifics, and how sex differences in communication are expressed in vocal interactions in general and vocal flexibility in particular. I studied two geographically and phylogenetically distant parrot species, the Australian galah (Eolophus roseicapillus) and the neotropical orange-fronted conure (Aratinga canicularis) to address these issues. I conducted four playback experiments either to wild, free-ranging individuals or to wild-caught captives held temporarily in aviaries. Two of these experiments address how parrots are using and interpreting rapid, short-term vocal flexibility during their interactions and how this differs by sex. The other two experiments address more broadly how male and female parrots respond to male and female affiliative and aggressive calls. This thesis demonstrates that in at least two species of parrots, males and females differ in how they rapidly modify their vocalizations during interactions with conspecifics. Despite sharing a repertoire of calls, both galahs and orange-fronted conures distinguish the sex of a caller based solely on acoustic cues, and males and females interact differently with conspecific callers, suggesting that the sex of interactants is a highly relevant factor even during interactions that do not seem to be primarily for the purpose of mate attraction. These experiments begin to shed light on the incredible intricacies of flexible parrot vocal communication.

The theory of sexual selection has drastically oriented research on acoustic communication in birds: males learn and sing conspicuous songs and females choose. Consequently, (1) female vocal production has been neglected, (2) birdcalls (most bird social communication) have been understudied. Birdcalls were supposed to be non-learned and no effect of the environment was expected on their structure (no flexibility, no learning). I thus focused my thesis on vocal flexibility (short-term) and vocal plasticity (developmental) of female vocalizations (mainly calls). I studied two contexts in which both sexes produce vocalizations: intrapair communication at the nest and parent-offspring communication. Do pairs express vocal flexibility in their calls in response to environmental noise? Is call development influenced by social environment? I studied two species: the white-throated dippers, Cinclus cinclus. (in which both sexes produce calls and songs) and the zebra finch, Taeniopygia guttata, (in which only males sing but both sexes use the same calls). I showed in both species, that in response to environmental noise, pairs increased the amplitude of their calls or song notes. In dippers, spectral flexibility was observed in song notes but not in calls. However, zebra finch calls showed spectral flexibility in response to noise. Both sexes showed similar changes in their calls: call spectral flexibility is not sex specific. Last, I showed that the structure of male begging calls changed in response to the early social environment, bringing evidence of early vocal plasticity in males. No change was found in females, showing that they either differ in their plasticity abilities or do not express plasticity because they receive different social feedbacks. My work showed that females and males show vocal flexibility but their vocal developmental trajectories may differ. Calls are thus good study objects to investigate sexual dimorphism in vocal behaviour.

Human language is unique among animals. We assume that complex cognitive capacities in general and language in particular evolved gradually and thus are manifest in different kinds and/or degrees in other animals demonstrating social communication. This assumption is supported by the fact that we can train social species from very different groups of animals (e.g. great apes, dolphins, dogs, parrots) to understand and in several cases even use abstract symbols for communication with humans and conspecifics. Even simple grammatical rules for sequences of 2-3 symbols can be trained to be understood by several species (e.g. great apes, dogs, dolphins). Even though human language training in these species takes considerable time and effort, it convinces us that cognitive foundations for language are present in other species, and, given the relevant selection pressures, symbolic communication could evolve in other species.

Neuroendocrine Regulation of Animal Vocalization: Mechanisms and Anthropogenic Factors in Animal Communication examines the underpinning neuroendocrine (NE) mechanisms that drive animal communication across taxa. Written by international subject experts, the book focuses on the importance of animal communication in survival and reproduction at an individual and species level, and the impact that increased production and accumulation of endocrine-disrupting chemicals (EDCs) can have on these regulatory processes. This book discusses sound production, perception, processing, and response across a range of animals. This includes insects, fish, bats, birds, nonhuman primates, infant humans, and many others. Some chapters analyze how neuroactive substances, endocrine control, and chemical pollution affect the physiology of the animal's perceptive and sound-producing organs, as well as their auditory and vocal receptors and pathways. Other chapters address the recent approaches governments have taken to protect against the endocrine disruption of animal (vocal) behaviors. The book is a valuable resource for researchers and advanced students seeking first-rate material on neuroendocrinological effects on animal behavior and communication. - Serves as the most comprehensive cross-taxa study of its kind, revolutionary in its focus on the impacts of EDCs on the processes guiding animal communication - Emphasizes the importance of production, perception and processing of acoustic vocalization for survival - Analyzes recent governmental policies and protections against the effects of EDCs on humans and wildlife

An introduction to chimpanzee behavior and conservation, synthesizing findings from long-term field studies in the African rainforest belt.

Vocal signals are central for social communication across a wide range of vertebrate species; consequently, it is critical to understand the mechanisms underlying the learning, control, and evolution of vocal communication. Songbirds are at the forefront of research into such neural mechanisms. Indeed, songbirds provide a particularly important model system for this endeavor because of the many parallels between birdsong and human speech. Specifically, (1) songbirds are one of the few vertebrate species that, like humans, learn their vocal signals during development, (2) the processes of song learning and control in songbirds shares many parallels with the process of speech acquisition in humans, and (3) there exist deep homologies between the circuits for the learning, control, and processing of vocal signals across songbirds and humans. In addition, because of the diversity of songbirds and song learning strategies, songbirds offer a powerful model system to use the comparative method to reveal mechanisms underlying the evolution of song learning and production. Taken together, research on songbirds can not only reveal general principles underlying vertebrate vocal communication but can also provide insight into potential mechanisms underlying the learning, control, and processing of speech. This volume will cover a range of topics in birdsong spanning multiple level of analysis. Chapters will be authored by the world’s leading experts on birdsong and will provide comprehensive reviews of the processes underlying song learning, of the neural circuits for song learning and control as well as for the extraction and processing of song information, of the selection pressures underlying song evolution, and of genetic and molecular mechanisms underlying the learning and evolution of song. The primary goals of this volume are to provide comprehensive, integrative, and comparative perspectives on birdsong and to underscore the importance of birdsong to biomedical research, evolutionary biology, and behavioral, systems, and computational neuroscience.The target audience of this volume will be graduate students, postdoctoral fellows, and established academics and neuroscientists who are interested in mechanisms of communication from an integrative and comparative perspective. The volume is intended to function as a high-profile and contemporary reference on current work related to the learning, control, processing, and evolution of birdsong. This volume will have broad appeal to comparative and sensory biologists, neurophysiologists, and behavioral, systems, and cognitive neuroscientists who attend meetings such as the Society for Neuroscience, the International Society for Neuroethology, and the Society for Integrative and Comparative Biology. Because of the relevance of birdsong research to understanding human speech, it is likely that the volume will also be of interest to speech researchers and clinicians researching communication, motor, and sensory processing disorders.

Via rhyming text, an introduction to the habits and characteristics of the parrot.