Ecology and Evolutionary Biology Commons^™

Constraints Of The Imagination: How Phenotypes Are Shaped Through Genetics, The Environment, And Development, Michelle Gilbert

Doctoral Dissertations

Phenotypic constraints are ubiquitous throughout nature, being found throughout all stages of life and at multiple different biological levels including cellular, genetic, environmental, behavioral, evolutionary, and developmental. These constraints have shaped, not only the natural world, but the way that we perceive what is possible, or impossible, an observation made clear by François Jacob in his 1977 paper “Evolution and Tinkering”. This is reflected in the literature, repeatedly, by the regular occurrence of densely packed visualization of phenotypic space that seemingly always have large areas that go unoccupied. Despite constrained regions of space being observable across countless taxa, identifying the …

Ecology And Phytochemistry Of The Non-Native Plant Thlaspi Arvense (Brassicaceae) In Subalpine Meadows Of Colorado, Usa, Elsa Cousins

Doctoral Dissertations

Climate change is altering ecosystems at multiple scales. Globally, warming temperatures and increasing irregularity of precipitation will have large scale impacts on species distribution and success. Locally, understanding species response to fine scale microhabitat variation can provide key insights into population adaptation. Non-native plants represent an opportunity to investigate population level response and adaptation to relatively novel combinations of biotic and abiotic environments. Subalpine meadows are at the intersection of biotic and abiotic change, as large-scale climatic shifts alter water and temperature regimes and species range shifts become increasingly common and larger in scale. This dissertation addresses these questions of …

Factors Influencing Primate Hair Microbiome Diversity, Catherine Kitrinos

Masters Theses

Primate hair is both a substrate upon which essential social interactions occur and an important host-pathogen interface. As commensal microbes provide important immune functions for their hosts, understanding the microbial diversity in primate hair could provide insight into primate immunity and disease transmission. While studies of human hair and skin microbiomes show differences in microbial communities across body regions, little is known about the nonhuman primate hair microbiome. In this study, we collected hair samples (n=159) from 8 body regions across 12 nonhuman primate species housed at 3 US institutions to examine 1) the diversity and composition of the primate …

De-Coding The Impact Of Evolved Changes In Gene Expression And Cellular Phenotype On Primate Evolution, Trisha Zintel

Doctoral Dissertations

The goal of the dissertation work outlined here was to investigate the influence of proximal processes contributing to evolutionary differences in phenotypes among primate species. There are numerous previous comparative analyses of gene expression between primate brain regions. However, primate brain tissue samples are relatively rare, and my results have contributed to the pre-existing data on more well-studied primates (i.e. humans, chimpanzees, macaques, marmosets) as well as produced information on more rarely-studied primates (i.e. patas monkey, siamang, spider monkey). Additionally, the primary visual cortex has not previously been as extensively studied at the level of gene expression as other brain …

Patterns Of Morphological Plasticity In Metriaclima Zebra And Danio Rerio Suggest Differently Canalized Phenotypes Due To Form-Function Relationships, Dylan Jockel

Masters Theses

In order to ascertain the degree of compatibility in developmental restructuring and behavioral plasticity between two fish species frequently made subject of laboratory research (Metriaclima zebra & Danio rerio), alternative trophic niche exposure experiments utilizing novel three-prong feeding treatments were conducted to obtain morphometric data, which demonstrated both species do bear some degree of plasticity. The results are somewhat complicated by differences in locality of detectable restructuring, which may be due to disparity in the form-function relationship for each species’ lineage. Each is notable in the manner of respective species’ jaw protrusion, as it is driven by anterior …

Impacts Of Genome And Nuclear Architecture On Molecular Evolution In Eukaryotes, Xyrus Maurer-Alcalá

Doctoral Dissertations

The traditional view of genomes suggests that they are static entities changing slowly in sequence and structure through time (e.g. evolving over geological time-scales). This outdated view has been challenged as our understanding of the dynamic nature of genomes has increased. Changes in DNA content (i.e. polyploidy) are common to specific life-cycle stages in a variety of eukaryotes, as are changes in genome content itself. These dramatic genomic changes include chromosomal deletions (i.e. paternal chromosome deletion in insects; Goday and Esteban 2001; Ross, et al. 2010), developmentally regulated genome rearrangements (e.g. the V(D)J system in adaptive immunity in mammals; Schatz …

Aggressive Signaling In New World Warblers, David Hof

Doctoral Dissertations

In many animal species, communication can enable individuals to resolve conflict without the high potential costs involved in direct fighting. During contests, animals may exchange information about their aggressive motivational state. A central question throughout the study of animal communication research has been whether animal signals convey reliable information, and this question has been particularly relevant to communication during conflicts where the evolutionary interests of competitors directly oppose. Deceptive signaling of aggressive motivation would be highly favored by natural selection because it could allow individuals to gain access to resources they might not gain through direct combat. However, selection should …

Regional Comparison Of Overwintering Mortality, Fecundity, And Virulence In The Hemlock Woolly Adelgid, Artemis Demas Roehrig

Masters Theses 1911 - February 2014

Throughout the eastern United States, the spread of the hemlock woolly adelgid, Adelges tsugae Annand, has caused high mortality of eastern hemlocks Tsuga canadensis (L.). We recorded overwintering survival and fecundity of A. tsugae, and tree new growth at sites in the northeastern and southeastern United States and in a common garden experiment in Massachusetts.

Overwintering mortality of A. tsugae was much higher in the north (87%) than the south (37%) in 2009, and showed significantly positive density-dependence in the north only. In 2010, overwintering mortality decreased in both regions but remained higher in the north (54%) than the …

A Phylogenetic Analysis Of Armored Scale Insects, Based Upon Nuclear, Mitochondrial, And Endosymbiont Gene Sequences, Jeremy C. Andersen

Masters Theses 1911 - February 2014

Armored scale insects (Hemiptera: Diaspididae) are among the most invasive insects in the world. They have unusual genetic systems, including diverse types of paternal genome elimination (PGE) and parthenogenesis. Intimate relationships with their host plants and bacterial endosymbionts make them potentially important subjects for the study of co- evolution. Also, in some groups, the adult female never sheds the second instars cuticle, and remains within its confines, a habit referred to as the pupillarial habit. Here we expand upon recent phylogenetic work (Morse and Normark 2006) by analyzing a partitioned dataset including armored scale and endoysmbiont DNA from one hundred …