About

Bruce Byers is an Associate Professor of Biology at the University of Massachusetts Amherst, specializing in the study of songbird vocalizations within the field of Organismic & Evolutionary Biology. His research focuses on explaining the patterned complexity of songbird vocalizations, which are used in structured communication systems that vary among species. He investigates how these vocalizations are transmitted through biological and cultural mechanisms, exploring the interplay of heredity and learning in the evolution of singing behavior. His work aims to understand how singing influences reproductive fitness and the evolutionary processes driving the development of specific song patterns. Byers employs a variety of approaches including detailed observation and description of songs, correlation studies between singing features and fitness components, field experiments to test the communicative functions of song features, and comparative analyses across species to examine ecological and life history influences on song variability. His research particularly emphasizes the distinction between songs used for mate attraction and those used for competition, focusing on wood warblers, where male-directed and female-directed songs evolve independently. This allows for a clearer understanding of the features that have evolved for different communicative purposes, contributing valuable insights into the adaptive significance of song in social and reproductive contexts.

Research topics

• Sociology
• Linguistics
• Geography
• Demography
• Biology
• Ecology

Selected publications

• Evening Grosbeak (Hesperiphona vespertina)

  Birds of the World · 2025-10-28 · 1 citations

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• Genetic analysis of <i>Cistothorus palustris</i> (Marsh Wren) across a broad transition zone in Southern Saskatchewan reveals deep divergence and little hybridization between two cultural phenotypes

  The Auk · 2025-10-13

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  Abstract We here explore the relationship between biological and cultural evolution in Cistothorus palustris (Marsh Wren), which across Canada and the United States can be easily differentiated into two geographic groups based on diagnostic western and eastern song types. The wren songs are culturally transmitted, as young males raised in the laboratory readily learn songs of either type. We find that, in cattail- and bulrush-dominated marshes across a &amp;gt; 400-km transition zone in southern Saskatchewan, males of both cultural traditions occur together and defend territories against each other; pure western and pure eastern singers are abundant, and relatively few males have learned songs of both phenotypes. To determine the genetic ancestry of singing males in these two cultural traditions, we generated reduced-representation genomic sequence data for birds from across this contact zone. We find exceptionally high genome-wide divergence between western and eastern singing Marsh Wrens from outside the contact zone (FST = 0.61), potentially the highest between any lineages that form a hybrid zone in the North American Great Plains. In the heart of the contact zone, genetic data indicate an overall low rate of hybrid ancestry, and ancestry is tightly coupled with male song type, suggesting that this cultural trait could play a role in maintaining a strong but imperfect degree of assortative mating. All 9 of the mixed singers (males with both western and eastern songs) that we sequenced were of predominantly eastern ancestry, with 6 of them having 100% eastern genotype. These mismatched individuals could play an outsized role in driving the ongoing generation of hybrid offspring and the introgression of eastern alleles into western populations. Taken together, these genomic and vocal datasets reveal that the western and eastern Marsh Wren song phenotypes represent deeply divergent parapatric lineages despite breeding side-by-side in the same marshes. Although all males are capable of learning the songs of the other genotype, they rarely do, and two cultural traditions representing two genetic ancestries appear to coexist stably in the Great Plains of southern Saskatchewan.

  PublisherDOI

• Chestnut-sided Warbler (Setophaga pensylvanica)

  Birds of the World · 2020-03-04 · 3 citations

  reference-entry1st authorCorresponding
  PublisherDOI

• Song learning by prairie warblers: When, where, and from whom

  Ethology · 2020

  1st authorCorresponding
  • Sociology
  • Geography
  • Ecology

  Abstract Songbirds of many species acquire their songs by imitating the songs of conspecific singers. Conclusive evidence of such imitation comes from controlled laboratory studies, but such studies do not reveal when and where songbirds learn their songs under natural conditions. To determine the timing and location of song learning in a population of prairie warblers, we compared the songs of yearling prairie warblers of known hatching location to the songs of other birds in the yearlings' natal and first breeding areas. The comparisons yielded a likely model song (and model singer) for each of the song types used by the focal yearlings. We supplemented our findings from the song comparisons with inferences drawn from an analysis of local geographic variation in songs. This analysis revealed that shared song types showed no tendency to be geographically clustered within the study area. Taken together, our data suggest that prairie warblers learn their songs during the hatch year, at locations somewhat distant (mean distance 1,437 m) from their natal site, most likely as birds wander about during the post‐fledging period.

  PublisherDOI

• Evening Grosbeak (Coccothraustes vespertinus)

  Birds of the World · 2020-03-04 · 3 citations

  reference-entrySenior author
  PublisherDOI

• Chestnut-sided warblers use rare song types in extreme aggressive contexts

  Animal Behaviour · 2017-02-17 · 14 citations

  article1st authorCorresponding
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• Biology : Life on Earth With Physiology Eleventh Edition

  2016-01-01

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• Song and Male Quality in Prairie Warblers

  Ethology · 2016-06-15 · 18 citations

  article1st authorCorresponding

  Abstract To determine if the songs of male prairie warblers could potentially reveal to female listeners information about the quality of singers, we compared various aspects of prairie warbler song structure and performance to attributes that might reflect a male singer's potential to enhance the fitness of his mate. We found that all the tested male attributes—arrival date, age, body size, annual survival, and fledging success—were associated with singing, most with multiple aspects of singing. Several of the song traits that were associated with potential indicators of male quality had also been found previously to be good predictors of female social mate choice. In particular, longer songs with longer elements, performed at lower frequency and with greater consistency, were associated with both female mate choice and potential indicators of quality. Thus, female prairie warblers may assess potential mates with the help of a set of song characteristics that collectively reveal an array of attributes that together indicate overall male quality.

  PublisherDOI

• A proxy of social mate choice in prairie warblers is correlated with consistent, rapid, low-pitched singing

  Behavioral Ecology and Sociobiology · 2015-05-20 · 16 citations

  article1st authorCorresponding
  PublisherDOI

• Migration and song elaboration in wood-warblers (<i>Geothlypis</i>)

  The Auk · 2014-12-03 · 9 citations

  article1st authorCorresponding

  Although some comparative studies of oscine songbirds have found that long-distance migration is positively correlated with elaborate songs, an analysis of singing by species in the genus Geothlypis (Parulidae) found no evidence of such a correlation. The migratory species in the genus sing relatively simple songs, whereas the singing of nonmigratory species varies; some species have simple songs, and others have more elaborate songs. Elaborate songs are found in the nonmigratory species G. semiflava, G. aequinoctialis, and G. poliocephala. For example, in Costa Rican populations of these species, songs are longer, contain more notes, have greater note-type diversity, and (in G. semiflava and G. aequinoctialis) have more phrase types than the songs of the migratory Geothlypis species. However, in other nonmigratory species (G. nelsoni, G. flavovelata, G. speciosa, and G. rostrata), the duration, note count, and note-type diversity of songs are similar to those of the migratory species. Thus, there seems to be no consistent relationship between migration and song elaboration in Geothlypis. In accordance with this inconsistency, ancestral-character-state reconstruction showed that evolutionary loss of migratory behavior was associated with increased song elaboration in some clades within the genus, but not in others. Overall, song variation in wood-warblers (Geothlypis) provides no support for the hypothesis that long-distance migration favors the evolution of elaborate songs.

  PublisherDOI

Frequent coauthors

• Donald E. Kroodsma

  11 shared

• David I. King

  Northern Research Station

  9 shared

• Michael E. Akresh

  4 shared

• Gerald Audesirk

  4 shared

• Teresa Audesirk

  4 shared

• David F. Westneat

  University of Kentucky

  3 shared

• Thorsten J. S. Balsby

  Aarhus University

  3 shared

• Herman L. Mays

  Marshall University

  3 shared