Biology Commons^™

Functional Morphology, Biomechanics, And Evolution Of Ruminant Mammals, Abby Vander Linden

Doctoral Dissertations

Ruminant mammals, including the families Bovidae, Cervidae, Tragulidae, Moschidae, Antilocapridae, and Giraffidae, display incredible past and present diversity in morphology, ecology, and behavior. They inhabit an impressive range of environments across North and South America, Europe, Asia, and Africa, and compel the fascination of naturalists and researchers alike with their charismatic social behavior and conspicuous cranial appendages. I explore the drivers and consequences of this spectacular diversity through a comparative morphological framework, biomechanical modeling approaches, and semi-parametric and likelihood-based methods for estimating state-dependent diversification rates across the ruminant phylogeny. Together, these investigations provide evidence for adaptation via correlated evolution of …

Vocal Performance In Songbirds: Territorial Defense And The Development Of Male Song And Female Mating Preferences, Dana L. Moseley

Doctoral Dissertations

The evolution of sexually selected signals has been a major topic of scientific research since Darwin. In recent years, scientists have focused on how elaborate signals can indicate honest information about the quality of their bearers, as predicted by reliability theory. A key concept relating to how mating displays could reliably reveal quality is "performance." Animals face limits in display production, and producing high-­‐performance displays depends on the adept coordination of multiple motor systems. Thus, by observing motor performance, signal-­‐receivers can assess the quality of signalers. Birdsong is a prime example of a display that involves motor challenges in its …

The Role Of Dawn Song In Tree Swallows And Its Place In The Diversity Of Oscine Song Learning, Benjamin Nichols Taft

Open Access Dissertations

Aspects of the behavioral ecology of bird song learning are examined in three parts. First, an approach from image analysis is extended to allow rapid, quantitative description of animal sounds. In this approach, sounds are summarized as sets of time-frequency-amplitude landmarks. Second, the role of dawn song in tree swallow (Tachycineta bicolor) breeding biology is examined. Song syllable sharing among tree swallows was found to be high among birds nesting at the same site, but sharing was lower between birds nesting at different sites. When birds nested at different sites, the distance between those sites was not related …

A Functional Approach To Sexual Selection, Duncan J. Irschick, Anthony Herrel, Bieke Vanhooydonck, Raoul Van Damme

Biology Department Faculty Publication Series

1. Sexual selection theory is a robust and dynamic field within evolutionary biology, yet despite decades of research, remarkably little is known of the mechanistic bases of mate choice and male competition.
2. Because many aspects of sexual selection involve dynamic movements, and are physically challenging, the limits of sexual selection may be defined by key functional and physiological variables (i.e. the ‘functional approach’).
3. We advocate the functional approach for providing mechanistic resolution on the adaptive basis of sexual structures and signals, the nature of mate choice and how males compete, among other issues.
4. An overview of recent work, highlighted in this …