NSF Award
2321788
Birds and humans have an overlapping hearing range, but this does not mean they are perceiving complex sounds the same way. In fact, birds have an auditory temporal processing ability that far exceeds humans. From research on humans, it has been shown that such temporal processing abilities make it easier to understand speech in noisy environments and facilitate the identification of familiar talkers. Thus far, there has been no research testing the function of bird’s enhanced temporal processing ability. This proposal will test the function of birds exceptional temporal processing ability. It would be striking if birds are using these fine acoustic details which lab studies have shown they are capable of hearing. Such acoustic details have so far been largely beyond the scope of what traditional biological approaches have been able to capture. Thus, this proposal may fundamentally impact how birdsong is described going forward. Reciprocally, studying bird species with such exceptional temporal processing abilities may have broader impact on research related to individual differences in hearing of people over their lifetime. Finally, both being around and listening to birds is something many people enjoy. Therefore, this proposal also includes developing an accessible multimedia outreach program. Too often disabled people are excluded from active participation in outreach programs due to different communication abilities. Furthermore, there is a powerful opportunity to leverage diversity in animal communication to help create inclusive spaces for thinking about and relating to diversity in human communication. <br/><br/>To understand mechanisms of social behavior and communication, it is critical to have a comprehensive understanding of the perceptual space, or ‘umwelt,’ of a species. This proposal combines expertise in social behavior with the precision of a psychophysical approach. A bird’s ability to discriminate fine acoustic details in vocalizations is about ten times better than a human’s ability. So far, this exceptional ability to discriminate acoustic fine structure (AFS) has been identified in all seven avian species studied. This proposal aims to discover potential functions of this perceptual ability in birds. To properly situate the perception of AFS in the natural ecology of birds, this proposal pursues three distinct lines of inquiry. (1) To determine whether perception of AFS shapes vocal learning, song learning experiments will be conducted using natural and artificial stimuli that vary in their complexity and type of AFS. (2) To test the effect of noise on an individual’s ability to perceive natural vocal signals, classic psychophysical experiments will be used. (3) To identify the role of AFS in shaping social communication, artificial and natural stimuli will be used to determine if AFS is important during courtship and pair bonding. Combined these three perspectives will clarify the function of bird’s perceptual ability in natural communicative contexts. Furthermore, these studies will provide a foundation for future research aiming to integrate basic perception and natural ethology more fully across taxa.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
