Biology ETDs

Publication Date

Spring 4-15-2017


What causes biological diversity to be unevenly apportioned across the Tree of Life? The pattern is widespread and well-characterized; but our understanding of processes underlying the taxonomic, phenotypic, and ecological disparities of clades remains incomplete. At least some of this disparity is due to clade-specific differences in the ability to respond to ecological opportunity, whereby access to, and exploitation of, different resources in ecological time drives evolutionary divergence and adaptive radiation. However, not all clades respond equivalently to ecological opportunity, and considerable heterogeneity therefore exists in diversification patterns across radiations.

This dissertation focuses on patterns and processes of diversification in ground-dwelling squirrels of the tribe Marmotini. It seeks to infer phylogeny and describe variation in ecological and phenotypic traits (patterns) and, ultimately, to relate those to the developmental, environmental, and evolutionary factors shaping them (processes). It integrates molecular, morphological, and environmental datasets derived from museum specimens at two taxonomic levels (across the entire tribe and within the genus Urocitellus). Results at each level are evaluated in the context of current evolutionary theory and practice, and these are used to determine whether evolutionary themes exist in marmotine radiation transcending taxonomic and phylogenetic scales.



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Department Name

UNM Biology Department

First Committee Member (Chair)

Joseph Cook

Second Committee Member

Steven Poe

Third Committee Member

Felisa Smith

Fourth Committee Member

James Degnan

Fifth Committee Member

Kristofer Helgen