Life Sciences 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 …

Population Genomics Of A Baboon Hybrid Zone In Zambia, Kenneth Lyu Chiou

Arts & Sciences Electronic Theses and Dissertations

Hybridization is increasingly recognized as a common, important process shaping the evolution of organisms including humans. Across hybrid zones, the genomes of incipient species are mixed and recombined through hybridization and backcrossing, creating conditions ideal for evaluating the actions of natural selection on gene variants in novel genomic contexts. This dissertation aims to increase our understanding of hybridization using a Zambian baboon study system in which two species, Kinda baboons (Papio kindae) and grayfoot baboons (Papio griseipes), hybridize despite exhibiting pronounced differences in body size and behavior. Using genome-wide genotypic data prepared using double-digest RADseq, I scan for genomic regions …

Hybridization Dynamics Of A Newly Discovered Parrotfish Swarm In The Tropical Eastern Pacific, Robert Barron

Honors Projects

Hybrid zones and their dynamics are important in the understanding of the genetic basis of reproductive isolation and speciation. This study seeks to investigate the hybridization dynamics of a Scarus hybrid swarm within the Tropical Eastern Pacific (TEP) that includes four phenotypically distinct species: S. perrico, S. ghobban, S. rubroviolaceus, and S. compressus. Genetic and population structure analyses of four nuclear loci and a mitochondrial locus revealed that one of the four species, S. compressus, was the result of two different hybrid crosses: S. perrico ✕ S. rubroviolaceus and S. perrico ✕ S. ghobban. A …

Some Like It Cold: The Relationship Between Thermal Tolerance And Mitochondrial Genotype In An Invasive Population Of The European Green Crab, Carcinus Maenas, Aidan Fisher Coyle

Honors Projects

Hybrid zones provide natural laboratories to study how specific genes, and interactions among genes, may influence fitness. On the east coast of North America, two separate populations of the European green crab (Carcinus maenas) have been introduced in the last two centuries. An early invasion from Southern Europe colonized New England around 1800, and was followed by a second invasion from Northern Europe to Nova Scotia in the early 1980s (Roman 2006). As these populations hybridize, new combinations of genes potentially adapted to different ends of a thermal spectrum are created in a hybrid zone. To test the hypothesis that …

Mating Patterns And Post-Mating Isolation In Three Cryptic Species Of The Engystomops Petersi Species Complex, Paula A. Trillo, Andrea E. Narvaez, Santiago R. Ron, Kim L. Hoke

Biology Faculty Publications

Determining the extent of reproductive isolation in cryptic species with dynamic geographic ranges can yield important insights into the processes that generate and maintain genetic divergence in the absence of severe geographic barriers. We studied mating patterns, propensity to hybridize in nature and subsequent fertilization rates, as well as survival and development of hybrid F₁ offspring for three nominal species of the Engystomops petersi species complex in Yasuní National Park, Ecuador. We found at least two species in four out of six locations sampled, and 14.3% of the wild pairs genotyped were mixed-species (heterospecific) crosses. We also found reduced …

Dna Sequencing And Taxonomy Of Unusual Serrate Juniperus From Mexico: Chloroplast Capture And Incomplete Lineage Sorting In J. Coahuilensis And Allied Taxa, Robert P. Adams, M. Socorro Gonzalez-Elizondo, Martha Gonzalez-Elizondo, David Ramirez Noya, Andrea E. Schwarzbach

Health & Biomedical Sciences Faculty Publications and Presentations

Analysis of nrDNA, petN-psbM, trnS-trnG, trmD-trnT, and trnF-trnL of Juniperus coahuilensis and allied taxa of Mexico found typical J. coahuilensis, as well as individuals with: coahuilensis cp and hybrid ITS; coahuilensis cp and novel ITS sequence (La Parrilla type); novel Blue Fruited cp (blue fruited taxon) and coahuilensis ITS; plus Blue Fruited cp and La Parrila ITS. nrDNA data was examined and found to detect hybridization, chloroplast capture and incomplete lineage sorting. In addition, a new taxon was found with Blue Fruited (Blue Fruited) cp and J. martinezii ITS, suggestive of chloroplast capture. New records of J. saltillensis were confirmed …

Panmixia And Limited Interspecific Introgression In Coyotes (Canis Latrans) From West Virginia And Virginia, Usa, Justin H. Bohling, Lauren L. Mastro, Jennifer R. Adams, Eric M. Gese, Sheldon F. Owen, Lisette P. Waits

USDA Wildlife Services: Staff Publications

The expansion of coyotes (Canis latrans) into the eastern United States has had major consequences for ecological communities and wildlife managers. Despite this, there has been little investigation of the genetics of coyotes across much of this region, especially outside of the northeast. Understanding patterns of genetic structure and interspecific introgression would provide insights into the colonization history of the species, its response to the modern environment, and interactions with other canids. We examined the genetic characteristics of 121 coyotes from the mid-Atlantic states of West Virginia and Virginia by genotyping 17 polymorphic nuclear DNA microsatellite loci. These …

A Comparative Analysis Of Geometric Morphometrics Across Two Pseudemys Turtle Species In East Central Virginia, Kristin C. Dillard

Theses and Dissertations

The phylogeny of the turtle genus Pseudemys is poorly understood. In Virginia, many turtles have been found with indicator traits of both eastern river cooters (Pseudemys concinna concinna) and northern red bellied cooters (Pseudemys rubriventris). This study explores morphological evidence for hybridization between the two species across three riverine sites in east central Virginia.

Museum voucher groups for each species were analyzed for relative shell height and plastron length. The shape of the plastral scutes and upper jaw were analyzed using landmark-based morphometric software. These metrics were compared with measurements taken from 188 field-caught Pseudemys specimens. …

Assessing The Genetic Status And Factors Leading To The Decline Of The Roanoke Bass (Ambloplites Cavifrons), Jackman C. Eschenroeder

Electronic Theses and Dissertations

Although numerous factors have led to the staggering declines in freshwater biodiversity throughout the United States and the world, habitat alteration and introduced species pose some of the greatest challenges to conservation efforts. Learning more about how these two factors lead to the decline of an endemic organism could help prevent the future loss of unique species and the premature conclusion of evolutionary trajectories. Roanoke bass (Ambloplites cavifrons) is a sport fish endemic to portions of the Roanoke, Chowan, Tar, and Neuse river basins of North Carolina and Virginia. This species has been in decline for many years, …

Effects Of Plasticity And Hybridization On Life History Traits In Arabidopsis Thaliana Ecotypes, Kattia Paola Palacio Lopez

Graduate College Dissertations and Theses

Understanding the strategies that plant populations implement to increase evolutionary responsiveness to better survive environmental changes induced by climate change is a critical challenge for ecology and evolutionary studies. This dissertation investigates the role of hybridization, local adaptation, and phenotypic plasticity in plant population responses to environmental change. Specifically, I utilized meta-analysis techniques to investigate the prevalence of local adaptation and phenotypic plasticity as the two main mechanisms used to adapt to heterogeneous environments, and experimentally explored the genetic pathway of plasticity in phenology traits such as bolting time in Arabidopsis thaliana under high temperatures. Furthermore, A. thaliana was used …