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Full-Text Articles in Population Biology

Brody-Bertalanffy Growth Curves From Tag And Recapture Studies On Cabezon (Scorpaenichthys Marmoratus) And Gopher Rockfish (Sebastes Carnatus) Of The Central Coast, Christie Yorke Dec 2011

Brody-Bertalanffy Growth Curves From Tag And Recapture Studies On Cabezon (Scorpaenichthys Marmoratus) And Gopher Rockfish (Sebastes Carnatus) Of The Central Coast, Christie Yorke

Biological Sciences

No abstract provided.


Review Of Rare: Portraits Of America's Endangered Species. By Joel Sartore., Jim Mason Oct 2011

Review Of Rare: Portraits Of America's Endangered Species. By Joel Sartore., Jim Mason

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Short of being in the presence of a creature, a really good photograph of one can also make a lasting impression. That is something RARE does compellingly, with exquisite portrait photos of 68 North American species that are dwindling dangerously in numbers or have recently recovered from the brink of extinction. Included are such Great Plains natives as the lesser prairie chicken, the interior least tern, and the black-footed ferret. All creatures were photographed with either a pure white or black background, but unconventional poses surprise the reader with each turn of the page, while creative framing and layout engage …


Historical Biogeography Of Nebraska Pronghorns (Antilocapra Americana), Justin D. Hoffman, Hugh H. Genoways, Rachel R. Jones Oct 2011

Historical Biogeography Of Nebraska Pronghorns (Antilocapra Americana), Justin D. Hoffman, Hugh H. Genoways, Rachel R. Jones

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Archeological and paleontological records indicate that the pronghorn (Antilocapra americana) have a history of at least 20,000 years of occurrence within the current boundaries of Nebraska. Pronghorns occurred throughout the state for much of its history. With the evidence at hand we concluded that the eastern boundary of the geographic distribution of the pronghorn south of the Niobrara River in Nebraska at the beginning of the 19th century was along the western perimeter of the eastern deciduous forest and tallgrass prairie. This excluded most of the easternmost tier of counties in the state. This geographic arrangement persisted throughout …


Extensive Clonal Spread And Extreme Longevity In Saw Palmetto, A Foundation Clonal Plant, Mizuki K. Takahashi, Liana M. Horner, Toshiro Kubota, Nathan A. Keller, Warren G. Abrahamson Ii Oct 2011

Extensive Clonal Spread And Extreme Longevity In Saw Palmetto, A Foundation Clonal Plant, Mizuki K. Takahashi, Liana M. Horner, Toshiro Kubota, Nathan A. Keller, Warren G. Abrahamson Ii

Faculty Journal Articles

The lack of effective tools have hampered our ability to assess the size, growth and ages of clonal plants. With Serenoa repens (saw palmetto) as a model, we introduce a novel analytical framework that integrates DNA fingerprinting and mathematical modelling to simulate growth and estimate ages of clonal plants. We also demonstrate the application of such life-history information of clonal plants to provide insight into management plans. Serenoa is an ecologically important foundation species in many Southeastern United States ecosystems; yet, many land managers consider Serenoa a troublesome invasive plant. Accordingly, management plans have been developed to reduce or eliminate …


Factors That Affect Harem Stability In A Feral Horse (Equus Caballus) Population On Shackleford Banks Island, Nc, Jessa Madosky Aug 2011

Factors That Affect Harem Stability In A Feral Horse (Equus Caballus) Population On Shackleford Banks Island, Nc, Jessa Madosky

LSU New Orleans Theses and Dissertations

Mammal species often live in social groups, but the factors that promote group cohesion can be difficult to analyze due to the prevalence of strong group affiliations. Feral horses maintain stable harems of one or two males and several females, and harem stability is strongly related to individual fitness. Anecdotal evidence and an early study in the non-breeding season suggest that management of the Shackleford Banks island horses with immunocontraception reduces harem stability in the population, providing an opportunity to study the factors that influence harem stability. I investigated the effects of the immunocontraceptive PZP on harem stability during the …


Interspecies Comparison Of Αii-Spectrin Abundance Between Chinook Salmon And Steelhead, Brielle D. Kemis, Ann L. Miracle, Katie A. Wagner, Christa M. Woodley Aug 2011

Interspecies Comparison Of Αii-Spectrin Abundance Between Chinook Salmon And Steelhead, Brielle D. Kemis, Ann L. Miracle, Katie A. Wagner, Christa M. Woodley

STAR Program Research Presentations

Salmonids, such as Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss), are a staple economic, recreational, tribal, and environmental resource, yet many populations are unsustainable. This study was part of a broad scale effort to monitor the impact of downstream migration obstacles on juvenile salmonid health and survival, which is an essential step towards increasing Smolt-to-Adult Return ratios (SARs). The objective of this study was to determine if juvenile Chinook salmon and steelhead exhibit differing quantities of alphaII-Spectrin Breakdown Products (SBDPs) over two consecutive spring migration periods, indicative of neurogenesis rate and/or biological response to head …


Land Cover And Topographic Effects On Cavity-Nesting Owl Occurrence And The Role Of Species Interactions In Structuring Cavity-Nesting Owl Communities, Micah Noel Scholer Aug 2011

Land Cover And Topographic Effects On Cavity-Nesting Owl Occurrence And The Role Of Species Interactions In Structuring Cavity-Nesting Owl Communities, Micah Noel Scholer

Boise State University Theses and Dissertations

Relatively little is known about the distribution, abundance, and population trends of many species of owls. Frequently, studies that describe owl distributions are accomplished by modeling characteristics of the habitat such as land cover and topographic features. However, the potential to model owl distributions as a function of species interactions has been largely unexplored. I investigated how habitat characteristics as well as species interactions shape owl distributions in the Western United States. Using occurrence data collected between 2009 and 2010 in the Boise National Forest, Idaho, I developed species distribution models for Flammulated Owls (Otus flammeolus) and Northern …


Biological Condition Of Money Pont Benthic Communities, Southern Branch Of The Elizabeth River (2010), Daniel M. Dauer Aug 2011

Biological Condition Of Money Pont Benthic Communities, Southern Branch Of The Elizabeth River (2010), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

The subtidal macrobenthic communities off Money Point in the Southern Branch of the Elizabeth River were quantitatively sampled in summer 2011. The designated Money Point study area will be a part of a sediment contaminant remediation effort. The primary objectives of this study were to: (1) characterize the biological health of the benthos of Money Point and (2) produce an historical data base that will allow an assessment of the effectiveness of the proposed sediment contamination remediation efforts with respect to Money Point benthos.

The most quantitative characterization of the benthos of the Elizabeth River watershed was the …


Avian Influenza In Migratory Birds In The United States, 2007–2009, And Effects Of September Hunting Seasons On Survival, Harvest, And Recovery Rates Of Canada Geese Banded In Southeast Nebraska, Scott R. Groepper Aug 2011

Avian Influenza In Migratory Birds In The United States, 2007–2009, And Effects Of September Hunting Seasons On Survival, Harvest, And Recovery Rates Of Canada Geese Banded In Southeast Nebraska, Scott R. Groepper

School of Natural Resources: Dissertations, Theses, and Student Research

Highly-pathogenic avian influenza virus (HPAIV H5N1) poses risks to wild birds, poultry, and humans. Personnel with the United States Department of Agriculture-Animal Plant Health Inspection Service-Wildlife Services, state, and tribal wildlife agencies collected 168,940 samples from migratory birds from 2007 to 2009 to test for presence of HPAIV H5N1. No HPAIV was found, but other subtypes were discovered, including H5 and H7. I estimated prevalence of avian influenza virus by flyway and found prevalence was lowest each year in the Atlantic Flyway (6.7%–8.3%), highest in the Pacific Flyway in 2007 (13.3%) and 2008 (13.4%), and highest in the Mississippi Flyway …


Historical Diversification Of Montane Herpetofauna Within And Between The Sierras Of Mexico, Robert William Bryson Jr. Aug 2011

Historical Diversification Of Montane Herpetofauna Within And Between The Sierras Of Mexico, Robert William Bryson Jr.

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Mexican highlands consist of four major mountain ranges spanning most of mainland Mexico. The evolutionary history of the Mexican highlands has been shaped by various geological and climatic events over the past several million years. The relative impacts of these historical events on diversification in montane taxa, however, remains uncertain. I used mitochondrial DNA data from three widely distributed species complexes of lizards as a model system to exemplify the potential roles of Neogene mountain formation and Quaternary climate change on timing and tempo of diversification across the Mexican highlands. My results suggested strong geographic partitioning of genetic variation …


Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida Aug 2011

Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ecological studies have shown worldwide that vegetation is being affected by climate change. Species are shifting to new elevations and physiographic positions to adapt to changes in their environment. More specifically, paleoecology studies in the Mojave Desert have shown shifting vegetation patterns in response to past warming and precipitation changes. Recent studies have shown mortality among desert plants related to extended drought and warming. However, few studies have shown how the geographic distribution of Mojave Desert species has changed during this most recent period of warming. This study addresses this gap in the literature by focusing on several plant species …


Phylogeography Of A Vanishing North American Songbird: The Painted Bunting (Passerina Ciris), Connie Ann Herr Aug 2011

Phylogeography Of A Vanishing North American Songbird: The Painted Bunting (Passerina Ciris), Connie Ann Herr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Studies of genetic variation within and between species can provide insights into their evolutionary history as well as important information for conserving biodiversity. An understanding of population processes can assist in the conservation of biodiversity by contrasting current versus historical patterns, and the processes that have generated these patterns. Genetic differentiation often coincides with significant geological or climatic changes that have shaped the sizes and locations of the species geographic range and altered the connectivity between populations over time. Phylogenetic and population genetic analyses can also provide a statistical framework for the investigation of how human processes such as habitat …


The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris Jul 2011

The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris

Department of Environmental Studies: Undergraduate Student Theses

Alliaria petiolata (Garlic Mustard) is a biennial alien invasive plant species of the Brassicacea family. It is responsible for displacing native plant species throughout North America and its management has proven to be extremely difficult. Recently several populations of Alliaria petiolata have been discovered in southwestern Lincoln, Nebraska. The spread of Alliaria petiolata is a concern for natural resource managers and the general public. Due to the difficulty of its control, Alliaria petiolata is capable of creating monocultures which diminish the aesthetic value of an ecosystem. While most commonly found in the understory of hardwood forests, it is capable of …


Herbicide-Resistant Risk Assessment: Response Of Common Nebraska Weeds To Dicamba Dose, Roberto J. Crespo Jul 2011

Herbicide-Resistant Risk Assessment: Response Of Common Nebraska Weeds To Dicamba Dose, Roberto J. Crespo

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Dicamba-resistant soybeans are being developed to provide an additional herbicide mechanism of action that can be used in soybean, and to provide a tool to help manage or mitigate the evolution of other herbicide-resistant weed populations. The objectives of this thesis were to assess the risk of common Nebraska weeds developing resistance to dicamba, quantify baseline dose-response to dicamba of high-risk weed species, and survey the variability in dicamba dose-response among populations of those species. Twenty-five weed scientists were asked to estimate the risk likelihood of ten weed species evolving resistance to dicamba following the commercialization of dicamba-resistant soybean. Palmer …


Patterns Of Transience, Sex Bias, And Body Mass In Open-Habitat Rodent Populations, Stephen Edward Rice Jul 2011

Patterns Of Transience, Sex Bias, And Body Mass In Open-Habitat Rodent Populations, Stephen Edward Rice

Biological Sciences Theses & Dissertations

Rodents are assumed to live their lives in circumscribed (natal) areas with males being more prone to disperse than females and juveniles more prone to disperse than adults. To test these assumptions we examined the initial captures of geographic populations of hispid cotton rat, meadow vole, prairie vole, and marsh rice rat obtained through capture-mark-recapture methods. Capture records were obtained from Kansas and Illinois from long-term studies, and through live-trapping in Chesapeake, Virginia. I evaluated proportions of residents and transients, adults and juveniles, and males and females for significant differences among seasons, years, and geographic locations. The overall body masses …


Phylogeography Of The Reef Fish Cephalopholis Argus(Epinephelidae) Indicates Pleistocene Isolation Across The Indo-Pacific Barrier With Contemporary Overlap In The Coral Triangle, Michelle R. Gaither, Brian W. Bowen, Tiana-Rae Bordenave, Luiz A. Rocha, Stephen J. Newman, Juan A. Gomez, Lynne Van Herwerden, Matthew T. Craig Jul 2011

Phylogeography Of The Reef Fish Cephalopholis Argus(Epinephelidae) Indicates Pleistocene Isolation Across The Indo-Pacific Barrier With Contemporary Overlap In The Coral Triangle, Michelle R. Gaither, Brian W. Bowen, Tiana-Rae Bordenave, Luiz A. Rocha, Stephen J. Newman, Juan A. Gomez, Lynne Van Herwerden, Matthew T. Craig

Fisheries Research Articles

Background

The Coral Triangle (CT), bounded by the Philippines, the Malay Peninsula, and New Guinea, is the epicenter of marine biodiversity. Hypotheses that explain the source of this rich biodiversity include 1) the center of origin, 2) the center of accumulation, and 3) the region of overlap. Here we contribute to the debate with a phylogeographic survey of a widely distributed reef fish, the Peacock Grouper (Cephalopholis argus; Epinephelidae) at 21 locations (N = 550) using DNA sequence data from mtDNA cytochrome b and two nuclear introns (gonadotropin-releasing hormone and S7 ribosomal protein).

Results

Population structure was significant …


Biology, Systematics, Phylogenetic Analysis And Dna Character-Based Species Diagnosis Of The False Root-Knot Nematode Nacobbus Aberrans (Thorne, 1935) Thorne & Allen 1944 (Nemata: Pratylenchidae), Angel Ramirez-Suarez Jun 2011

Biology, Systematics, Phylogenetic Analysis And Dna Character-Based Species Diagnosis Of The False Root-Knot Nematode Nacobbus Aberrans (Thorne, 1935) Thorne & Allen 1944 (Nemata: Pratylenchidae), Angel Ramirez-Suarez

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The False Root-Knot nematode Nacobbus aberrans is a plant parasitic nematode that causes yield losses in several crops and plant protection agencies have established regulations to prevent infestations from spreading to new agricultural areas. The taxonomic status of the nematode has been the subject of controversy due to wide degree of variation exhibited by the species. This variability has led to the suggestion that N. aberrans is actually a species complex rather than a single species. In order to test this hypothesis, we compared twelve N. aberrans populations, which include isolates from western Nebraska, two distinct regions of Mexico and …


Influence Of Wave Action On Mytilus Californianus Mussel Beds, Jaclyn Mann Jun 2011

Influence Of Wave Action On Mytilus Californianus Mussel Beds, Jaclyn Mann

Biological Sciences

No abstract provided.


Life History Benefits Of Residency In A Partially Migrating Pond-Breeding Amphibian, Kristine L. Grayson, Larissa L. Bailey, Henry M. Wilbur Jun 2011

Life History Benefits Of Residency In A Partially Migrating Pond-Breeding Amphibian, Kristine L. Grayson, Larissa L. Bailey, Henry M. Wilbur

Biology Faculty Publications

Species with partial migration, where a portion of a population migrates and the other remains residential, provide the opportunity to evaluate conditions for migration and test mechanisms influencing migratory decisions. We conducted a five-year study of two populations of red-spotted newts (Notophthalmus viridescens), composed of individuals that either remain as residents in the breeding pond over the winter or migrate to the terrestrial habitat. We used multistate mark-recapture methods to (1) test for differences in survival probability between migrants and residents, (2) determine if migrants breed every year or skip opportunities for reproduction, and (3) estimate the frequency …


Population Dynamics Of The Western Prickly Pear, Opuntia Macrorhiza (Cactaceae), Kathleen H. Keeler, Brigitte Tenhumberg Jun 2011

Population Dynamics Of The Western Prickly Pear, Opuntia Macrorhiza (Cactaceae), Kathleen H. Keeler, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Although most cacti that have been studied are long lived, following individually marked plants in Boulder County, Colorado, for >7 years, we determined that average life span of Opuntia macrorhiza, the western prickly pear, is 3 years. A few individuals probably live >10 years. Vegetative reproduction, produced by rooting of cladodes, exceeded reproduction by germination and establishment from seeds. Both types of new recruits, from vegetative reproduction and seeds, had higher death rates than established plants. Size and frequency of flowering increased with age, although size both increased and decreased, sometimes dramatically, between years. Flowering correlated more strongly with …


Botteri's Sparrow (Peucaea Botterii) Occurs In Northern Coahuila, Mexico, Paul Van Els, Ricardo Canales-Del-Castillo, John Klicka Jun 2011

Botteri's Sparrow (Peucaea Botterii) Occurs In Northern Coahuila, Mexico, Paul Van Els, Ricardo Canales-Del-Castillo, John Klicka

Ornithology Program (HRC)

Botteri’s Sparrow (Peucaea botterii) occurs widely in the shrub-grasslands of southern North America. We report a breeding population of the species in the Sierra de la Encantada of northern Coahuila, Mexico, ~80 km from the Big Bend area of Texas and >300 km from the nearest previously known breeding range in southern Coahuila and central Chihuahua. We captured three individuals, which show a mostly gray dorsal coloration, suggestive of the texana subspecies, occurring from southern Texas to northern Veracruz. The exact affinity of the northern Coahuila population still needs to be ascertained. The presence of Botteri’s Sparrow in northern Coahuila …


A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt May 2011

A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt

United States Department of Agriculture Wildlife Services: Staff Publications

Techniques to monitor populations of feral swine (Sus scrofa) relative to damage control activities are needed on rangelands. Our objectives were to describe and assess a mark–recapture technique using tetracycline hydrochloride (TH) for monitoring feral swine populations. We established bait stations at study sites in southern and central Texas. During 1 d, we replaced normal soured corn bait with bait containing TH and counted the number of feral swine that consumed bait with observers. We conducted feral swine removal using box-style traps and helicopters, at which time we collected teeth for TH analysis. In southern Texas, we estimated …


The Role Of Historical And Contemporary Processes On Phylogeographic Structure And Genetic Diversity In The Northern Cardinal, Cardinalis Cardinalis, Brian T. Smith, Patricia Escalante, Blanca E. Hernandez-Banos, Adolfo G. Navarro-Siguenza, Sievert Rohwer, John Klicka May 2011

The Role Of Historical And Contemporary Processes On Phylogeographic Structure And Genetic Diversity In The Northern Cardinal, Cardinalis Cardinalis, Brian T. Smith, Patricia Escalante, Blanca E. Hernandez-Banos, Adolfo G. Navarro-Siguenza, Sievert Rohwer, John Klicka

Ornithology Program (HRC)

Background

Earth history events such as climate change are believed to have played a major role in shaping patterns of genetic structure and diversity in species. However, there is a lag between the time of historical events and the collection of present-day samples that are used to infer contemporary population structure. During this lag phase contemporary processes such as dispersal or non-random mating can erase or reinforce population differences generated by historical events. In this study we evaluate the role of both historical and contemporary processes on the phylogeography of a widespread North American songbird, the Northern Cardinal, Cardinalis cardinalis …


The Decline And Conservation Status Of North American Bumble Bees, Jonathan Berenguer Koch May 2011

The Decline And Conservation Status Of North American Bumble Bees, Jonathan Berenguer Koch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several reports of North American bumble bee (Bombus Latreille) decline have been documented across the continent, but no study has fully assessed the geographic scope of decline. In this study I discuss the importance of Natural History Collections (NHC) in estimating historic bumble bee distributions and abundances, as well as in informing current surveys. To estimate changes in distribution and relative abundance I compare historic data assembled from a >73,000 specimen database with a contemporary 3-year survey of North American bumble bees across 382 locations in the contiguous U.S.A. Based on my results, four historically abundant bumble bees, B. …


Does Thermal Stress Cause Females Of The Plant Bryum Argenteum To Manipulate The Sex Ratios Of Their Offspring?, Elisha Rhodes, Lloyd Stark Apr 2011

Does Thermal Stress Cause Females Of The Plant Bryum Argenteum To Manipulate The Sex Ratios Of Their Offspring?, Elisha Rhodes, Lloyd Stark

Festival of Communities: UG Symposium (Posters)

About half of all moss taxa exhibit female-biased sex ratios, and bryophyte male rarity remains largely unexplained. One possible explanation is differential stress tolerance of spores due to maternal sporophyte manipulation during stress. To test this hypothesis, sporophytes of the species Bryum argenteum were subjected to thermal stress and observed for growth abnormalities and sporophyte abortions. Data display a correlation between increased temperature and increased sporophyte abortions as well as increased time to complete meiosis, possibly indicating decreased fitness. Continued global warming may create more stressful environments for sporophytes resulting in the elimination of males from local populations.


Review Of Nature's Ghosts: Confronting Extinction From The Age Of Jefferson To The Age Of Ecology. By Mark V. Barrow, Jr., Peter A. Bednekoff Apr 2011

Review Of Nature's Ghosts: Confronting Extinction From The Age Of Jefferson To The Age Of Ecology. By Mark V. Barrow, Jr., Peter A. Bednekoff

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

The saving of bison occupies a central place in Nature's Ghosts, but Mark Barrow's chronicle extends over a century both before and after. The story starts with Thomas Jefferson and fossils that came to be recognized as mastodons, mammoths, and giant ground sloths. "Jefferson and most of his contemporaries were certain that the natural world was orderly, static, and new." In such a worldview, extinction was unthinkable. Fossil evidence plus the historical extinctions of dodos, moas, and great auks forced reconsideration.

This book ranges across centuries and continents, and only a few parts of it are explicitly about the Great …


Health And Fertility Implications Related To Seasonal Changes In Kidney Fat Index Of White-Tailed Jackrabbits In South Dakota, Dustin Schaible, Charles D. Dieter Apr 2011

Health And Fertility Implications Related To Seasonal Changes In Kidney Fat Index Of White-Tailed Jackrabbits In South Dakota, Dustin Schaible, Charles D. Dieter

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

White-tailed jackrabbit (Lepus townsendii) populations in the Northern Plains have been in a general decline for the past decade or longer. A suggested reason for this population decline was reduced body condition of individual jackrabbits due to habitat changes. In order to evaluate body condition, we determined the kidney fat index of 314 white-tailed jackrabbits harvested in 44 counties throughout South Dakota. We removed and weighed kidneys and all perirenal fat associated with the kidneys from collected jackrabbits. We measured kidney weight to determine times of high metabolic activity as indicated by an increase in mass. Body condition was …


Governance Of The Western Rock Lobster Fishery And Marine Stewardship Council Principle 3 Effective Management, Department Of Fisheries Apr 2011

Governance Of The Western Rock Lobster Fishery And Marine Stewardship Council Principle 3 Effective Management, Department Of Fisheries

Fisheries Occasional Publications

No abstract provided.


Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis Apr 2011

Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis

School of Biological Sciences: Dissertations, Theses, and Student Research

Accurate knowledge of species boundaries and species phylogeny are fundamental to testing hypotheses of recent evolutionary processes, but the estimation of these partitions is challenging due both to inherent confusion about what is being estimated as well as the data available to estimate them. Using multilocus data from mtDNA, microsatellites, and nuclear locus sequences of over 1100 individuals, we delimited eight separately evolving species of Cichla rather than the 15 described. Among species we found evidence of rare but widespread introgressive hybridization, while within these species we observed evidence of long-term gene exchange and constrained evolutionary trajectories. In most cases …


Effects Of Water Quality On Genetic Variation On The Brackish-Water Rotifer Brachionus Plicatilis, Kayla I. Hinson^, Elizabeth J. Walsh* Mar 2011

Effects Of Water Quality On Genetic Variation On The Brackish-Water Rotifer Brachionus Plicatilis, Kayla I. Hinson^, Elizabeth J. Walsh*

COURI Symposium Abstracts, Spring 2011

Impacts of water quality on the genetic structure of aquatic organisms have not been well characterized. Unfavorable conditions may result in loss of species diversity and/ or select for tolerant genotypes. We investigated whether aquatic pollutants affect the genetic diversity of the rotifer Brachionus plicatilis, common in saline systems. We predict that the genetic diversity of B. plicatilis will decrease with lower water quality. An urban population (Ascarate Lake, El Paso Co., TX) was compared with a non-impacted population (Figure 8 Lake, Bottomless Lakes, NM). Basic water chemistry parameters were measured along with heavy metals concentrations. Genetic variation is …