Ecology and Evolutionary Biology Commons^™

Genetic Diversity And Differentiation Patterns In Micromeria From The Canary Islands Are Congruent With Multiple Colonization Dynamics And The Establishment Of Species Syngameons, Manuel Curto, Pamela Puppo, S. Kratschmer, H. Meimberg

Biological Sciences Faculty Research

Background

Especially on islands closer to the mainland, such as the Canary Islands, different lineages that originated by multiple colonization events could have merged by hybridization, which then could have promoted radiation events (Herben et al., J Ecol 93: 572–575, 2005; Saunders and Gibson, J Ecol 93: 649–652, 2005; Caujapé-Castells, Jesters, red queens, boomerangs and surfers: a molecular outlook on the diversity of the Canarian endemic flora, 2011). This is an alternative to the scenario where evolution is mostly driven by drift (Silvertown, J Ecol 92: 168–173, 2004; Silvertown et al., J Ecol 93: 653–657, 2005). In the former case …

The Population Genetics Of Morro Bay Eelgrass (Zostera Marina), Julia Gardner Harencar

Master's Theses

Seagrass populations are in decline worldwide. Zostera marina (eelgrass), one of California’s native seagrasses, is no exception to this trend. In the last 8 years, Morro Bay, California has lost 95% of its eelgrass. Eelgrass is an ecosystem engineer, providing important ecosystem services such as sediment stabilization, nutrient cycling, and nursery habitats for fish. The failure of recent restoration efforts necessitates a better understanding of the causes of eelgrass decline in this estuary. Previous research on eelgrass in California has demonstrated a link between population genetic diversity and eelgrass bed health, ecosystem functioning, and resilience to disturbance and extreme climatic …

Evolutionary Genetic Aspects Of Host Association In Generalist Ectoparasites, Benoit Talbot

Electronic Thesis and Dissertation Repository

Despite the use of the host for dispersal by most parasite species, the extremely loose relationship typical between highly mobile hosts and generalist ectoparasites may lead to very different gene flow patterns between the two, leading in turn to different spatial genetic structure, and potentially different demographic history. I examined how similar gene flow patterns are between Cimex adjunctus, a generalist ectoparasite of bats present throughout North America, and two of its key bat hosts. I first analyzed the continent-scale genetic structure and demographic history of C. adjunctus and compared it to that of two of its hosts, the …

Mhc Class Iiβ Diversity As A Correlate Of Neutral-Locus Similarity And Diversity, And A Predictor Of Overwinter Return, In Song Sparrows (Melospiza Melodia), Matthew J. Watson

Electronic Thesis and Dissertation Repository

Abstract

The major histocompatibility complex (MHC) is a family of genes involved with recognizing pathogens and mounting an immune response. Parasite-mediated selection often favours heterozygosity at MHC because MHC-diverse individuals recognize a wider range of pathogens. Because migratory birds encounter many pathogens, I hypothesized that MHC diversity predicts overwinter and juvenile survivorship in song sparrows (Melospiza melodia). I found no correlation between MHC diversity and neutral-locus (microsatellite) heterozygosity, suggesting that measures of neutral and adaptive genetic diversity provide complementary rather than redundant information. However, pairwise similarity at MHC predicted pairwise similarity at microsatellite loci. In contrast to my hypothesis, MHC …

The Landscape Of Extreme Genomic Variation In The Highly Adaptable Atlantic Killifish, Noah M. Reid, Craig E. Jackson, Don Gilbert, Patrick Minx, Michael J. Montague, Thomas H. Hampton, Lily W. Helfrich, Benjamin L. King, Diane E. Nacci, Neel Aluru

Dartmouth Scholarship

Understanding and predicting the fate of populations in changing environments require knowledge about the mechanisms that support phenotypic plasticity and the adaptive value and evolutionary fate of genetic variation within populations. Atlantic killifish (Fundulus heteroclitus) exhibit extensive phenotypic plasticity that supports large population sizes in highly fluctuating estuarine environments. Populations have also evolved diverse local adaptations. To yield insights into the genomic variation that supports their adaptability, we sequenced a reference genome and 48 additional whole genomes from a wild population. Evolution of genes associated with cell cycle regulation and apoptosis is accelerated along the killifish lineage, which …