Benedict Lab

Animal Communication and Social Behavior


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Research interests in the Benedict lab include animal communication and social behavior. Most projects use birdsong as a model system for studying the evolution of communication signals at multiple levels. By describing large-scale patterns of trait diversification we attempt to understand the long-term consequences of evolution, and by examining the real-time function of vocal traits we can learn how evolutionary mechanisms shape behavioral characteristics.

 


Projects:

Habitat use, social behavior and communication among cliff-associated wren species of the Colorado Front Range

Canyon wrens (Catherpes mexicanus) and rock wrens (Salpinctes obsoletus) coexist in the rocky cliffs of northern Colorado and exploit similar ecological niches. We are conducting research to understand how they use resources, how they partition (or fail to partition) space, and how they communicate interspecifically and intraspecifically.

Read about our research in The Loveland Reporter Herald or the UNC Mirror.

Click the appropriate word to listen to canyon wren calls (2 birds), female song, and one, two, three different song types from a single male in Larimer County, Colorado. Click here to listen to a series of rock wren songs recorded from a male just outside of Fort Collins, Colorado. The track includes one call plus 18 songs representing 10 song types.


The form and function of song in female birds

Although female songbirds in temperate regions of the world sing less frequently than males, the songs of females may be highly functional with unique evolutionary histories and important fitness consequences. In collaboration with researchers at the Cornell Lab of Ornithology and elsewhere, our lab has been working to increase documentation of female song and to study how this communication signal has evolved differently in diverse lineages. Research related to this project has examined female song evolution in New World warblers, female song function in wrens and female song prevalence across all avian species.


Song evolution in the genus Cisticola
Collaborator: Dr. Rauri Bowie (UC Berkeley)

This project asks questions about the evolution of vocalizations, including solo song and duets, within a large group of old-world species. By combining behavioral, ecological, geographic and phylogenetic information, our research takes a synthetic approach to understanding how evolutionary processes generate avian trait diversity.The genus Cisticola presents an excellent study system for examining patterns of song evolution because it includes nearly fifty species with distinctive vocal traits and varied levels of relatedness. Morphological traits are extremely conserved among cisticolas but song traits vary widely, suggesting an important role for song in maintaining species boundaries. Initial results support the assumption that cisticola songs are species-specific. Nevertheless, songs may be highly variable. Our analyses examine how both song form and song variability evolve.


Song and duet evolution among New World sparrows
Collaborator: Dr. Carla Cicero (UC Berkeley)

Vocal duets are given by at least 17 species of New World sparrows from several genera, including Aimophila and Melozone. Recently revised species names reflect relationships that have long been suggested by previous researchers, notably Wolf in a 1977 manuscript. Similarity in duet form, as well as other ecological and behavioral traits may reflect evolutionary relationships better than the morphological traits that were originally used to designate genera. We are examining trait evolution within a phylogenetic context. Preliminary results suggest that behavioral traits, including duet presence and form, are strongly conserved in this group. Because birds sing a primary song that differs from the duet song, we have the opportunity to examine the evolution of multiple vocalization types. By doing so we are learning how different evolutionary processes and pressures can shape vocalizations used in different contexts.

Singing together: California towhee vocal duet function

This research investigated the functional significance of vocal communication behaviors among California Towhees (Melozone crissalis). Early studies established the social and ecological context of communication behaviors in order to better assess the function of vocal signals. California towhees are highly sedentary and exhibit life-long social pair bonds. As a result of this sedentary life-history, most individual vocalizations are not used to establish territory or attract a mate, differentiating California towhees from the majority of species that serve as models of bird song evolution. One uncommon vocalization type employed by California towhees is a duet performed by social mates. Duetting behavior is thought to exist in less than 3% of bird species, and is interesting because the highly coordinated nature of the signal suggests that it has been favored by a process of natural selection acting on two individuals simultaneously. Experimental playback and male removal studies have indicated that California towhee duets serve multiple functions, including coordination of pair-based activities such as defending resources and raising offspring. Successful offspring production is a critical determinant of evolutionary success, and experiments have indicated that California towhees of both sexes are highly attentive to offspring distress signals. Surprisingly, in light of their strong paternal care, social pair-bonds and duetting behavior, California towhees are not genetically monogamous. A molecular genetic analysis of parentage indicated that 42% of nests in one study population contained extra-pair young. This represents the first demonstration of frequent extra-pair paternity in a duetting species.

University of Northern Colorado - School of Biological Sciences


Photo: Sarah Knutie, Wendy Fair, Nat Warning. Illustrations from Lynes 1930