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Full-Text Articles in Ecology and Evolutionary Biology

Prehistoric Foraging Strategies In The Piute Valley Of Southern Nevada, Christopher Alan Brosman May 2012

Prehistoric Foraging Strategies In The Piute Valley Of Southern Nevada, Christopher Alan Brosman

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Piute Valley of Southern Nevada is an incredibly diverse but arid zone in the eastern portion of the Mojave Desert. Most of this diversity can be attributed to the elevation shifts ranging from the Colorado River basin to the peaks of the surrounding mountain ranges. These peaks and valleys provide a multitude of resource zones in which prehistoric hunter-gatherers could provision themselves throughout the year. For this thesis I have used archaeological survey, paleo-climate models, life-sciences data and ethnographic research to perform an in-depth land use analysis of prehistoric forager adaptations to this challenging but life-sustaining environment.

Recent investigations …


Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering January 1, 2012 To March 31, 2012, Margaret N. Rees Mar 2012

Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering January 1, 2012 To March 31, 2012, Margaret N. Rees

Get Outdoors Nevada

  • The number of records in the volunteer database increased by 4.96% over the last quarter. The database now contains 7,423 records.
  • Results show an average of 1,259 visits per month, and with an average of 3,015 pages viewed per month.
  • Get Outdoors Nevada supported 14 volunteer events in a variety of ways. These events utilized 364 volunteers whom contributed approximately 2,414 hours of service.
  • Three community outreach events were attended, resulting in 293 direct contacts with 50 names added to the database.
  • The automated volunteer orientation training project has been completed and disks have been delivered to the 4 agencies. …


Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending December 31, 2011, Margaret N. Rees Dec 2011

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending December 31, 2011, Margaret N. Rees

Limnological Studies

Project 1

  • Technical assistance with the implementation of the Interagency Monitoring Action Plan (IMAP) for Quagga Mussels is ongoing; remaining analyses are underway with report delivery rescheduled for 05/2012.
  • Data have been delivered for Veliger abundance and settlement at different depths of Lake Mead with report delivery re-scheduled for 05/2012.
  • Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay
  • The Interagency Quagga Mussel Meeting was held on 11/17/2011; the next meeting is scheduled for 02/16/2011.

Project 2

  • Appendix 7, an addition to the Long-term Limnological and Aquatic Resource Monitoring and Research Plan for Lakes Mead and Mohave, has …


Environmental Impact Of The Three Kids Mine Tailings, Henderson, Nv, Ji Hye Park Dec 2011

Environmental Impact Of The Three Kids Mine Tailings, Henderson, Nv, Ji Hye Park

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research focused on the distribution of the Three Kids Mine tailings in surface soils in and around the mine in Henderson, Nevada. It is situated next to the communities of Calico Ridge and Lake Las Vegas Resort, and, just the west of the Lake Mead Recreation area. Even though the mine has been inactive for almost 50 years (1917-1961), tailing piles and other sources of contamination on the mine are currently exposed to the atmosphere. In this study, surface soil samples were collected along eight transects emanating from the center of Three Kids Mine tailing piles up to five …


A Landscape Approach To Late Prehistoric Settlement And Subsistence Patterns In The Mojave Sink, Tiffany Ann Thomas Dec 2011

A Landscape Approach To Late Prehistoric Settlement And Subsistence Patterns In The Mojave Sink, Tiffany Ann Thomas

UNLV Theses, Dissertations, Professional Papers, and Capstones

The environment of the Late Prehistoric period (1200 A.D. to Historic Contact) Mojave Sink was wetter than modern conditions. The settlement and subsistence patterns of the occupants of the region during this period were driven by the availability of water, subsistence resources, raw material sources, and tradition. These people utilized the regional landscape based upon the seasonal availability of these resources. Supplemental agricultural production has been proposed for the Mojave River Delta due to the more favorable environmental conditions of this period. If agriculture was being practiced it would have affected the regional land-use patterns. For this thesis I propose …


Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda Dec 2011

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …


Microbial Impacts On Endocrine Disrupting Contaminants: Las Vegas Wash And Lake Mead, Nevada, Susanna May Blunt Dec 2011

Microbial Impacts On Endocrine Disrupting Contaminants: Las Vegas Wash And Lake Mead, Nevada, Susanna May Blunt

UNLV Theses, Dissertations, Professional Papers, and Capstones

International concern over endocrine disrupting chemicals (EDCs) has become heightened in recent years as more studies reveal their persistence in the environment and their detrimental effects on wildlife. However, little is known about the role of microorganisms in the fate and transport of these compounds in surface waters. Las Vegas Wash, a stream flowing into Lake Mead and fed primarily by treated wastewater effluent, provided a unique experimental system in which to study the role microorganisms play in the dispersal of these compounds in aquatic systems. Samples were collected from the Las Vegas Wash downstream of the Las Vegas Valley's …


Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas Oct 2011

Effects Of Climate Change On Spring Ecosystem Hydroecology As A Guide To Developing Alternative Water Policies, Scott Mensing, Saxon E. Sharpe, Scott Bassett, Don Sada, Jim Thomas

Climate Change Seminar Series (NNE)

Hydroecology: the interface of ecological systems and water which combines the scientific disciplines of hydrology and ecology

Goal: evaluate the hydrologic and climate history using pollen, loss on ignition, total inorganic carbon, and invertebrates from spring sediments in Spring Valley, Eastern Nevada and Snake Valley, Western Utah


Mojave Applied Ecology Notes Fall 2011, E. Cayenne Engel, Scott R. Abella, Kathryn A. Prengaman, Jason Whited, Peter Michel Oct 2011

Mojave Applied Ecology Notes Fall 2011, E. Cayenne Engel, Scott R. Abella, Kathryn A. Prengaman, Jason Whited, Peter Michel

Mojave Applied Ecology Notes

Paper on impacts of Mojave wildfires through time published, possibilities of catastrophic Mt. Charleston forest fires, vegetation mapping at three national parks, UNLV library’s special collections, and the benefits of scientific publications to managers and stakeholders


Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending September 30, 2011, Margaret N. Rees Sep 2011

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending September 30, 2011, Margaret N. Rees

Limnological Studies

Project 1

  • Technical assistance with the implementation of the Interagency Monitoring Action Plan (I-MAP) for Quagga Mussels is ongoing. During this quarter, processing of all 2010 juvenile/adult samples was completed; remaining analyses are underway. The project team assisted NPS with 2011 collections.
  • A final report on Veliger abundance and settlement at different depths of Lake Mead is in preparation for delivery at the end of November 2011; sample analysis continues for Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay with report delivery planned for the end of November 2011.
  • The Interagency Quagga Mussel Meeting was held on …


The Use Of Chloramines To Eradicate Quagga Mussel Larvae, Trea Lacroix, Kumud Acharya Aug 2011

The Use Of Chloramines To Eradicate Quagga Mussel Larvae, Trea Lacroix, Kumud Acharya

Undergraduate Research Opportunities Program (UROP)

Quagga Mussels, Dressenia bugensis, are a growing problem in the western United States, particularly in their ability to infest underwater infrastructures and clog water intake pipes and screens of power and treatment plants. Chlorine has been found to be the most effective chemical to get rid of veligers (planktonic larval form of quagga mussels) in the pipes. However, chlorine leaves a residue called trihalomethane, which is a carcinogen at higher concentrations. The purpose of this project is to test the effectiveness of an alternate chemical, chloramines (chlorine and ammonia), which leaves behind little to no residual trihalomethane. Upon experimentation with …


Magnetosome Genes In The Gammaproteobacterium Strain Bw-2, Lucero Rivera, Denis Trubitsyn, Dennis A. Bazylinski Aug 2011

Magnetosome Genes In The Gammaproteobacterium Strain Bw-2, Lucero Rivera, Denis Trubitsyn, Dennis A. Bazylinski

Undergraduate Research Opportunities Program (UROP)

Magnetotactic bacteria (MTB) biomineralize intracellular nanometer-sized, magnetic crystals surrounded by a lipid bilayer membrane known as magnetosomes. These crystals, which consist of magnetite (Fe3O4) or greigite (Fe3S4), causes the cell to align along the geomagnetic field lines as they swim, a phenomenon known as magnetotaxis. Strain BW-2 is a magnetite-producing magnetotactic bacterium isolated from Badwater Basin, Death Valley National Park (California) and is one of only two species of MTB that are known to phylogenetically belong to the Gammaproteobacteria class of the Proteobacteria phylum. The biomineralization of magnetite in magnetotactic bacteria is mediated by a series of genes that include …


Biological Effects On Serpentinite Weathering, Mary H. Evert, Julie Baumeister, Elisabeth Hausrath Aug 2011

Biological Effects On Serpentinite Weathering, Mary H. Evert, Julie Baumeister, Elisabeth Hausrath

Undergraduate Research Opportunities Program (UROP)

Serpentinites, perhaps more than any other rock type, control the composition and evolution of the development of the surrounding ecosystems. The bulk chemistry of serpentinite rocks, high in Mg and trace elements, and low in nutrients such as Ca, K, P, and N, causes an extreme and stressful environment for ecosystems. However, the role that those serpentine ecosystems play in development of serpentine soils has not been examined.

Due to the unusual chemistry of serpentine soils, serpentine ecosystems have deeper and better-developed root systems than other ecosystems. The rhizosphere of serpentine systems, documented to produce abundant organic acids and siderophores, …


Effects Of Climate Change On The Viability Of The Devils Hole Pupfish, Matthew Heuton, Stanley D. Hillyard, Frank Van Breukelen Aug 2011

Effects Of Climate Change On The Viability Of The Devils Hole Pupfish, Matthew Heuton, Stanley D. Hillyard, Frank Van Breukelen

Undergraduate Research Opportunities Program (UROP)

Devils hole is an unusual, cavernous, aquifer-fed its ideal temperature range. spring in Death Valley National Park. It is the only home to a critically endangered species, Cyprinidon diabolis, a.k.a. The Devils Hole Pupfish. C. diabolis allows us a unique look at the impact of climate change on a species that has no gene flow and no possibility of escape from its current habitat. Climate change affects ectotherms (cold-blooded animals) tremendously since their body temperature is subject to changes in the temperature of their environment. In the case of C. diabolis, they are subject to high temperatures year round, around …


Isolation, Characterization, And Genome Sequence Of The First Representative Of A Novel Class Within The Chloroflexi That Is Abundant In Some U.S. Great Basin Hot Springs And May Play Important Roles In N And C Cycling, Jeremy A. Dodsworth, Senthil K. Murugapiran, Jonathan Gevorkian, James Han, Tanja Woyke, Susan M. Lucas, Sam Pitluck, Len Pennacchio, Lynne Goodwin, Brian P. Hedlund Aug 2011

Isolation, Characterization, And Genome Sequence Of The First Representative Of A Novel Class Within The Chloroflexi That Is Abundant In Some U.S. Great Basin Hot Springs And May Play Important Roles In N And C Cycling, Jeremy A. Dodsworth, Senthil K. Murugapiran, Jonathan Gevorkian, James Han, Tanja Woyke, Susan M. Lucas, Sam Pitluck, Len Pennacchio, Lynne Goodwin, Brian P. Hedlund

Undergraduate Research Opportunities Program (UROP)

A thermophilic, facultatively microaerophilic, heterotrophic bacterium, designated strain JAD2, was isolated from sediments of Great Boiling Spring (GBS), an ~80oC, circumneutral hot spring in the Great Basin GB). The strain grew anaerobically on yeast extract or peptone with an optimal growth temperature of 70-75oC. Growth was stimulated by addition of 0.01 atm O2 to the culture vessel headspace, but was inhibited by higher concentrations (0.2 atm). Cells of JAD2 formed non-motile filaments ranging from 10 to >300 μm in length, which typically decreased in length during stationary phase. 16S rRNA gene-targeted pyrotag sequencing and clone library data suggest that close …


A Spatial And Temporal Analysis Of Microbial Communities In Great Boiling Spring, Nevada, U.S.A., Jessica K. Guy, Joseph P. Peacock, Jeremy A. Dodsworth, Tanja Woyke, Tijana G. Del Rio, Brian P. Hedlund Aug 2011

A Spatial And Temporal Analysis Of Microbial Communities In Great Boiling Spring, Nevada, U.S.A., Jessica K. Guy, Joseph P. Peacock, Jeremy A. Dodsworth, Tanja Woyke, Tijana G. Del Rio, Brian P. Hedlund

Undergraduate Research Opportunities Program (UROP)

Great Boiling Spring (GBS) is a large, circumneutral, long residence time geothermal spring in the US Great Basin. Twelve samples were taken from four different sediment sites and the planktonic community in the bulk water of GBS on up to four different dates. Microbial community composition and diversity was assessed by using a barcoded, improved universal primer set targeting the V8 portion of the 16S rRNA gene and PCR. Over 200,000 products were sequenced using the Roche 454 GS FLX Titanium System. Sediment and planktonic microbial communities were distinct with very little overlap, regardless of the sampling location or temperature. …


Evaluating Species Responses To Climate Change Using Ecological Niche Modeling And Genetic Data, Jeanette Perry Aug 2011

Evaluating Species Responses To Climate Change Using Ecological Niche Modeling And Genetic Data, Jeanette Perry

Undergraduate Research Opportunities Program (UROP)

The current and projected future warming trends together with degradation of habitats throughout much of the Great Basin and Columbian Plateau represent real threats to many species occupying these regions. If we can determine the impacts of past climatic changes on the distribution of species, we can obtain a better understanding of the future impacts of projected climatic trends on many species in these regions. My results with the Great Basin Pocket Mouse (Perognathus parvus) may be relevant to conservation ecologists and resource managers attempting to protect several Endangered Species Act candidates, such as the pygmy cottontail (Brachylagus idahoensis). I …


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 …


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 …


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 …


Walking Box Ranch Planning And Design Quarterly Progress Report: Period Ending July 10, 2010, Margaret N. Rees Jul 2011

Walking Box Ranch Planning And Design Quarterly Progress Report: Period Ending July 10, 2010, Margaret N. Rees

Walking Box Ranch

  • UNLV participated in several meetings with BLM regarding updating the current Task Order, obtaining a two-year no-cost extension for the two Assistance Agreements, and to develop the future WBR operating agreement between BLM and UNLV
  • UNLV met with Sara Moffatt, one of Senator Reid’s staff, to provide an update on project progress. UNLV also requested the Senator’s support in obtaining additional funding for the project for construction, and also for UNLV to bridge the transition from construction through the first two years of operation.
  • UNLV held several internal meetings to advance planning for a July VA meeting with BLM to …


How Well Do U.S. Forest Service Terrestrial Ecosystem Surveys Correspond With Measured Vegetation Properties?, Scott R. Abella Jul 2011

How Well Do U.S. Forest Service Terrestrial Ecosystem Surveys Correspond With Measured Vegetation Properties?, Scott R. Abella

Life Sciences Faculty Research

No abstract provided.


Mojave Applied Ecology Notes Summer 2011, Scott R. Abella, Charles W. Denton, David G. Brewer, Rory W. Steinke, Wayne A. Robbie, W. Wallace Covington, E. Cayenne Engel, Ross Guida Jul 2011

Mojave Applied Ecology Notes Summer 2011, Scott R. Abella, Charles W. Denton, David G. Brewer, Rory W. Steinke, Wayne A. Robbie, W. Wallace Covington, E. Cayenne Engel, Ross Guida

Mojave Applied Ecology Notes

Thoughts on fire possibilities on Mount Charleston, estimating historical densities of Ponderosa pine in northern AZ, over-understory changes in the Spring Mountains, seeding effectiveness in Red Rock Canyon, workshop announcements.


Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending June 30, 2011, Margaret N. Rees Jun 2011

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending June 30, 2011, Margaret N. Rees

Limnological Studies

Project 1

  • Technical assistance with the implementation of the Interagency Monitoring Action Plan (I-MAP) for Quagga Mussels is ongoing. During this quarter, analysis was completed for 42 juvenile/adult samples and analyses of the remaining samples are underway.
  • As of 7/07/11 all sample sets will have been collected for Veliger abundance and settlement at different depths of Lake Mead; sampling continues for Growth of adult quagga mussels within Las Vegas Wash/Las Vegas Bay.
  • The Interagency Quagga Mussel Meeting was held on 05/17/11; the next meeting is scheduled for 08/25/11.

Project 2

  • Appendix 7, an addition to the Long-term Limnological and Aquatic …


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 …


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 …


Estimating Wildfire Potential On A Mojave Desert Landscape Using Remote Sensing And Field Sampling, Peter F. Van Linn Iii May 2011

Estimating Wildfire Potential On A Mojave Desert Landscape Using Remote Sensing And Field Sampling, Peter F. Van Linn Iii

UNLV Theses, Dissertations, Professional Papers, and Capstones

Landscape level wildfire prediction can be used to allocate wildfire resources and guide land management practices. Wildfire prediction in arid habitats in the Southwestern United States is of specific concern because of the negative ecological impacts of fire on desert habitats and the current lack of accurate fire prediction tools for such areas. This study examines the ability to predict previous fire occurrences and estimate future fire potential using satellite imagery and on the ground field survey techniques along with ignition potential data (lightning strikes and distance to roads), topographical data (elevation and aspect), and climate information (maximum and minimum …


Relationships Of Exotic Plant Invasions With Biological Soil Crust, Desert Pavement, And Soil Carbon In The Eastern Mojave Desert, Adria Decorte May 2011

Relationships Of Exotic Plant Invasions With Biological Soil Crust, Desert Pavement, And Soil Carbon In The Eastern Mojave Desert, Adria Decorte

UNLV Theses, Dissertations, Professional Papers, and Capstones

In a matter of 50 years, exotic annual plants have become widespread in the Mojave Desert, contributing to drastic landscape changes such as those caused by recent fires. Invasions by exotics threaten native Mojave Desert plant communities by altering community functions (e.g. fire regimes) and by reducing plant diversity. Because it is not practical, or even possible, to eradicate these exotics, developing effective prevention techniques is the key to controlling these invasions.

This thesis used a greenhouse experiment, a field experiment, and a correlational field study to examine the affect soil surface types have on the establishment of three exotic …


Molecular Evolution And Historical Biogeography Of New World Birds, Brian T. Smith May 2011

Molecular Evolution And Historical Biogeography Of New World Birds, Brian T. Smith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Deciphering the patterns of how biodiversity has evolved across time and space has remained a fundamental objective for biologists for the last 200 years. Researchers are faced with the challenge of interpreting the complexity of evolutionary patterns that have been generated over the deep history of the Earth. The advancement of DNA sequencing technology has yielded a new and powerful genetic toolkit that has allowed biologists to address novel evolutionary questions. For my dissertation research, I used molecular genetics and a statistical framework to study the evolution and historical biogeography of birds distributed in North and South America. My dissertation …


Phylogeography Of Three Heteromyid Taxa: Insight On The Evolution Of A North American Arid Grassland Rodent Guild, Sean A. Neiswenter May 2011

Phylogeography Of Three Heteromyid Taxa: Insight On The Evolution Of A North American Arid Grassland Rodent Guild, Sean A. Neiswenter

UNLV Theses, Dissertations, Professional Papers, and Capstones

Revealing how communities are shaped by abiotic and biotic factors plays a central role in biogeographic and comparative phylogeographic studies. The biogeography of North American arid grasslands is explored using nuclear and mitochondrial DNA from three groups of heteromyid rodents that are broadly sympatric in aridlands across western North America. Phylogenetic and molecular clock analyses are used to estimate the timing of divergences within each group. A general pattern of late Miocene divergence and expansion of lineages in each of the groups that is coincident with the rapid expansion of arid grasslands at the time. The initial divergence is followed …