Acoustic partnership : vocal communication at the cornerstone of monogamy in birds – Acoustic partnership

The biological basis of social attachment has attracted interest for 15 years. Biology thus joined Human Sciences in the effort towards an understanding of social bonding existing in Humans as well as in many animal social groups. Because of its importance in Human social system, the monogamous pair-bond has been extensively studied in mammal model systems. Nevertheless, the adaptive value and evolutionary origin of the ‘animal marriage’ remain puzzling in many cases. Social monogamy is exceptionally rare in mammals, but represents about 90 percent of all bird species. Surprisingly, our current knowledge of the biology of pair-bonding in birds as well as of the functional emerging properties of this social organization is poor. The pair-bond in birds represents a real partnership. Mates work as a team during chicks feeding and synchronize their foraging activity. Mates may also repel together predators or join forces in aggressive encounters with competitors. The monogamous pair-bond is thus an excellent example of cooperative behavior that relies on coordination between mates. Coordination and synchrony are reached by constant communication between the partners. As generally in birds, acoustic communication plays a central role in this process. The study of acoustic communication is thus of high relevance to the understanding of monogamy in birds.
The Zebra finch (Taeniopygia guttata) is a gregarious songbird that forms monogamous pair-bonds. It represents the most widely used model system for the study of songbird acoustic communication from behavior to brain since the 70s. Moreover, this species has also been used extensively for the study of mate choice, parental care and reproductive investment. Thus, the zebra finch is a well-suited model system to study the communication basis and properties of monogamous pair-bonding in songbirds.
In a previous ANR project (ANR-06-blanc-293), partner 1 and 2 of the present project investigated the behavioral and neurobiological basis of vocal recognition in zebra finches (Vignal et al. 2004, 2008a, 2008b). In a recent field experiment on wild zebra finches (collaboration with Pr. S. Griffith, Macquarie University, Australia), we showed that mates performed interactive vocal duets at nest that could strengthen the pair bond (Elie et al. 2010). We also showed in a lab experiment that the pair bond constitutes a social partnership that structures vocal communication at the level of the social group (Elie et al. in press ; Elie et al. in revision). Building up on these previous published results, we propose to establish (1) how differences in the level of coordination and communication between partners relate to pair fitness components, (2) how social interactions and acoustic communication extend beyond the pair bond to the social group, and (3) the neurobiological and physiologic implications and constraints of pair bonding. In order to fulfill these aims, we will use a multidisciplinary approach involving bioacoustics, behavioral biology, but also physiology and neurobiology. By studying animals both in the lab and in the field, we will be able to draw conclusions with significance in an ecological and evolutionary framework, which should be of interest for high-ranked international journals. Because it will participate in the broader understanding of the communication basis of cooperative partnership, the results of such a study will be of interest in field as diverse as behavioral biology, Human sciences and economics.