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2012

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Articles 1 - 30 of 416

Full-Text Articles in Ecology and Evolutionary Biology

The Effect Of Temperature On Seed Quality And Quantity In Crosses Between European (Populus Tremula) And Hybrid Aspens (P. Tremula X P. Tremuloides), L. Koviuranta, T. Latva-Karjanmaa, P. Pulkkinen Dec 2012

The Effect Of Temperature On Seed Quality And Quantity In Crosses Between European (Populus Tremula) And Hybrid Aspens (P. Tremula X P. Tremuloides), L. Koviuranta, T. Latva-Karjanmaa, P. Pulkkinen

Aspen Bibliography

Hybrid aspen (Populus tremula L. Populus tremuloides Michx.) plantations are expanding in Fennoscandia and the Baltic countries; however, the possible effects of plantations on the native European aspen (P. tremula) and the level of gene flow between European and hybrid aspen have not been investigated. We studied seed quantity and quality in intraspecific and interspecific crosses of the European and hybrid aspens over a two year period. In order to study whether elevated temperatures due to climate change would benefit the species differently, we performed the crosses in different temperatures. In both years, interspecific crosses produced more seeds with higher …


Bmp Planning To Address Urban Runoff: Plaster Creek Watershed Sustain Pilot, Tetra Tech, Inc. Dec 2012

Bmp Planning To Address Urban Runoff: Plaster Creek Watershed Sustain Pilot, Tetra Tech, Inc.

Watershed Reports

The Plaster Creek watershed is tributary to the Grand River in west Michigan. Plaster Creek is one of several impaired streams in this area, located in metropolitan Grand Rapids. There are several listed impairments for the Creek including 1) other indigenous aquatic life and wildlife, 2) warm water fishery, and 3) total and partial body contact recreation. Total maximum daily load (TMDL) studies were completed in 2002 for biota and E. coli to address the listed impairments. In 2008, a watershed management plan (WMP) was developed which outlines an implementation plan for water quality improvement in the watershed. This pilot …


Promoting Amphibian Conservation Through The College Classroom: Detection Of Batrachochytrium Dendrobatidis Among Local Amphibians, Julie Wunder, Noel Lampazzi, Kelsey Acre, Nicholas Bent, Sadie Canter, Alexandra Chapman, Margaret Davies, David Kashan, Jonathan Keiley, Rachel Macintyre, Tamara Milton, Kara Weichler, Matthew Wilson, Mizuki Takahashi Dec 2012

Promoting Amphibian Conservation Through The College Classroom: Detection Of Batrachochytrium Dendrobatidis Among Local Amphibians, Julie Wunder, Noel Lampazzi, Kelsey Acre, Nicholas Bent, Sadie Canter, Alexandra Chapman, Margaret Davies, David Kashan, Jonathan Keiley, Rachel Macintyre, Tamara Milton, Kara Weichler, Matthew Wilson, Mizuki Takahashi

Faculty Journal Articles

Many global amphibian declines have been linked to the fungal pathogen Batrachochytrium dendrobatidis (Bd). The knowledge on Bd distribution provides a fundamental basis for amphibian conservation planning. Yet, such Bd distribution information is currently insufficient, in particular at a regional scale. The college classroom provides an excellent opportunity to expand the knowledge of Bd distribution. Here we provide an example of such research projects to detect Bd prevalence among local amphibians in a college course setting and present the results of work conducted in central Pennsylvania, USA. We collected toe clips and conducted PCR assays of six species, …


Forest Regeneration On The Osa Peninsula, Costa Rica, Manette E. Sandor Dec 2012

Forest Regeneration On The Osa Peninsula, Costa Rica, Manette E. Sandor

Master's Theses

Woody species diversity of secondary forest has the potential to converge with that found in old growth forest. This study is the first to examine multiple aspects of species and reproductive trait diversity, and their relationship to each other, across a successional chronosequence. Species richness and species diversity increases with increasing age of forest. Diaspore size and diversity as well as fruit size generally increased with increasing age of forest, but fruit size diversity did not. Abundance of animal-dispersed species increased whereas wind-dispersed species decreased in abundance over succession. Insect-pollinated individuals were most abundant overall. Diaspore diversity, pollination diversity, and …


Nursing Females Are More Prone To Heat Stress: Demography Matters When Managing Flying-Foxes For Climate Change, Stephanie T. Snoyman, Jasmina Munich, Culum Brown Dec 2012

Nursing Females Are More Prone To Heat Stress: Demography Matters When Managing Flying-Foxes For Climate Change, Stephanie T. Snoyman, Jasmina Munich, Culum Brown

Ecological Impacts of Climate Change Collection

Determining the underlying mechanisms responsible for species-specific responses to climate change is important from a species management perspective. The grey-headed flying-fox, Pteropus poliocephalus, is listed as vulnerable but it also a significant pest species for orchardists and thereby presents an interesting management conundrum. Over the last century, the abundance of the grey-headed flying-fox, P. poliocephalus, in Australia has decreased due to a variety of threatening processes but has increased in abundance in urban areas. These flying-foxes are highly susceptible to extreme heat events which are predicted to increase in the future under climate change scenarios. Exceptionally hot days result in …


Investigating The Compatibility Between Natura 2000 Site Protection And Geomorphological Landscapes, Faye Zammit Dec 2012

Investigating The Compatibility Between Natura 2000 Site Protection And Geomorphological Landscapes, Faye Zammit

Masters Theses, 2010-2019

Natura 2000 was established under the 1992 Habitats Directive as a EU wide network of nature protection areas by ensuring long-term survival of Europe’s most valuable and threatened species and habitats. Under the Natura 2000 scheme, there are a total of 32 protection areas in both Malta and Gozo. The different structural properties of the various rock layers results in various characteristic formations which are of ecological importance providing important refuge for many Maltese flora and fauna. In Malta, the different geomorphologic features are mainly a result of tectonic movement in which some are still dynamic and over the years …


Understanding Marine Ecosystem Services In Malta: A Focus On Climate Regulation, Nursery Habitat And Recreational Services, Erin Marie Reilly Dec 2012

Understanding Marine Ecosystem Services In Malta: A Focus On Climate Regulation, Nursery Habitat And Recreational Services, Erin Marie Reilly

Masters Theses, 2010-2019

The research explored the relationship that people have with marine environments around Malta through the framework of ecosystem services with the idea that the results of this research could be used as a starting point for the development of a management plan for the marine environment around Malta. Surveys were conducted targeting residents, tourists, and divers to gain an understanding of stakeholder perception of the threats facing climate regulation, provision of nursery habitat and recreation. These data were used to develop a GIS where essential areas and impacts were compared and areas of potential conflict were identified. There were significant …


The Debate On Marine Mammals In Captivity, Lorna C. Scribner Dec 2012

The Debate On Marine Mammals In Captivity, Lorna C. Scribner

Honors Theses

Are marine mammal species better off today because of captivity? Is captivity ethical and should it be continued? As this debate grows stronger, both of these sides of the argument offer substantial evidence in their favor. In this paper, I discuss data for both sides and evaluate the justifications of marine mammal captivity. Ideally, no matter the outcome, this research will educate the public on influential factors of wild and captive populations.


Distribution And Social Structure Of An Estuarine Bottlenose Dolphin (Tursiops Truncatus) Population In Northern South Carolina, Jamie L. Brusa Dec 2012

Distribution And Social Structure Of An Estuarine Bottlenose Dolphin (Tursiops Truncatus) Population In Northern South Carolina, Jamie L. Brusa

Electronic Theses and Dissertations

Information regarding habitat preference of apex predators may pinpoint areas dense in resources such as prey species. Knowledge of how animals use their habitat can enable the classification and targeted management of important habitat features. This study was conducted to determine the distribution and social structure of an inshore population of bottlenose dolphins within the North Inlet-Winyah Bay estuary in northern South Carolina. Photo-identification surveys were conducted along defined transect routes. Home ranges of individual dolphins were calculated using the minimum convex polygon method and the fixed kernel density method using Geographic Information System (GIS) software. Mean group sizes and …


Stream-Associated Amphibian Habitat Assessment In The Portland-Vancouver Metropolitan Region, Andrew Evans Dietrich Dec 2012

Stream-Associated Amphibian Habitat Assessment In The Portland-Vancouver Metropolitan Region, Andrew Evans Dietrich

Dissertations and Theses

This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with …


Assessment Of Land Use And Neotropical Herpetofauna Along Steep Gradients Of Elevation In An Ecuadorian Ramsar Wetland Site #1143, Nicholas K. Henke Dec 2012

Assessment Of Land Use And Neotropical Herpetofauna Along Steep Gradients Of Elevation In An Ecuadorian Ramsar Wetland Site #1143, Nicholas K. Henke

Electronic Theses and Dissertations

Using a comparative ecological approach, over the course of 18 days at the transition from a particularly wet to dry season in 2010, I assessed herpetofaunal assemblages and related abiotic parameters (i.e., photosynthetically active radiation, specific conductance, temperature and coarse woody debris) between contiguous forest and human impacted areas along three paired transects across the steep elevation gradient at Laguna de Cube, Ramsar site # 1143. Visual encounter surveys were used to capture herpetofauna with species being processed (e.g., weight, digit length, photographed) and identified to the lowest taxonomic level possible. After evaluating transect data for pooling (i.e., no significant …


Five New Species Of Chaerilus Simon, 1877 From China, Indonesia, Malaysia, Philippines, Thailand, And Vietnam (Scorpiones: Chaerilidae), František Kovařík Dec 2012

Five New Species Of Chaerilus Simon, 1877 From China, Indonesia, Malaysia, Philippines, Thailand, And Vietnam (Scorpiones: Chaerilidae), František Kovařík

Euscorpius

Chaerilus cimrmani sp. n. from Thailand, C. seiteri sp. n. from Philippines (Negros Island), C. solegladi sp. n. from Indonesia and Malaysia (Borneo Island), C. terueli sp. n. from Vietnam (Côn Son Island), and C. wrzecionkoi sp. n. from China (Tibet) are described. A key to all species of the genus Chaerilus Simon, 1877 is also presented.


Three New Species Of Compsobuthus Vachon, 1949 From Yemen, Jordan, Israel, And Somaliland (Scorpiones: Buthidae), František Kovařík Dec 2012

Three New Species Of Compsobuthus Vachon, 1949 From Yemen, Jordan, Israel, And Somaliland (Scorpiones: Buthidae), František Kovařík

Euscorpius

Compsobuthus krali sp. n. of the werneri group from Yemen, C. levyi sp. n. of the werneri group from Jordan and Israel, and C. somalilandus sp. n. of the acutecarinatus group from Somaliland are described. A key to all species of the genus Compsobuthus Vachon, 1949 is presented.


Moving Forward: Preventing Water Shortage For Nevada, Sandra Blandon, Brianna Lyon Dec 2012

Moving Forward: Preventing Water Shortage For Nevada, Sandra Blandon, Brianna Lyon

Anthropology 100: Feast and Famine In a Global World Poster Assignment

Southern Nevada is located in the arid Mojave Desert, which averages about 4 inches of rain each year. Southern Nevada gets about 90% of its water supply from the Colorado River. Seven western states and Mexico share the river. This means that The Colorado River provides water to 25 million people.


Positive Relationships Between Association Strength And Phenotypic Similarity Characterize The Assembly Of Mixed-Species Bird Flocks Worldwide, Hari Sridhar, Umesh Srinivasan, Robert A. Askins, Julio Cesar Canales-Delgadillo, Chao-Chieh Chen, David N. Ewert, George A. Gale, Eben Goodale, Wendy K. Gram, Patrick J. Hart, Keith A. Hobson, Richard L. Hutto, Sarath W. Kotagama, Jessie L. Knowlton, Tien Ming Lee, Charles A. Munn, Somchai Nimnuan, B. Z. Nizam, Guillaume Péron, V. V. Robin, Amanda D. Rodewald, Paul G. Rodewald, Robert L. Thomson, Pranav Trivedi, Steven L. Van Wilgenburg, Kartik Shanker Dec 2012

Positive Relationships Between Association Strength And Phenotypic Similarity Characterize The Assembly Of Mixed-Species Bird Flocks Worldwide, Hari Sridhar, Umesh Srinivasan, Robert A. Askins, Julio Cesar Canales-Delgadillo, Chao-Chieh Chen, David N. Ewert, George A. Gale, Eben Goodale, Wendy K. Gram, Patrick J. Hart, Keith A. Hobson, Richard L. Hutto, Sarath W. Kotagama, Jessie L. Knowlton, Tien Ming Lee, Charles A. Munn, Somchai Nimnuan, B. Z. Nizam, Guillaume Péron, V. V. Robin, Amanda D. Rodewald, Paul G. Rodewald, Robert L. Thomson, Pranav Trivedi, Steven L. Van Wilgenburg, Kartik Shanker

Biology Faculty Publications

Competition theory predicts that local communities should consist of species that are more dissimilar than expected by chance. We find a strikingly different pattern in a multicontinent data set (55 presence-absence matrices from 24 locations) on the composition of mixed-species bird flocks, which are important sub-units of local bird communities the world over. By using null models and randomization tests followed by meta-analysis, we find the association strengths of species in flocks to be strongly related to similarity in body size and foraging behavior and higher for congeneric compared with noncongeneric species pairs. Given the local spatial scales of our …


Marine Fungi Of U.S. Gulf Of Mexico Barrier Island Beaches: Biodiversity And Sampling Strategy, Allison Kathleen Walker Dec 2012

Marine Fungi Of U.S. Gulf Of Mexico Barrier Island Beaches: Biodiversity And Sampling Strategy, Allison Kathleen Walker

Dissertations

Marine fungi are an important but often overlooked component of marine ecosystems. Primarily saprotrophic, they are vital to coastal nutrient cycling processes and food webs. However, basic marine fungal distribution data are lacking in many parts of the world, as is knowledge of the sampling intensity required to characterize the biodiversity of these communities. The roles of substrate, season and latitude in shaping intertidal ascomycete community structure were examined for the U.S. Gulf of Mexico, and the role of sampling frequency on species richness estimates was also addressed. Best sampling practices were developed and 750 collections of beach detritus, sand …


Phenotypic Plasticity Of Oral Jaw Dentition In Archosargus Probatocephalus, Cynthia E. Worcester Dec 2012

Phenotypic Plasticity Of Oral Jaw Dentition In Archosargus Probatocephalus, Cynthia E. Worcester

Masters Theses & Specialist Projects

Phenotypic plasticity, the capacity of a single genotype to exhibit variable phenotypes in different environments, is common in many species. A sample of wild caught Archosargus probatocephalus, also known as sheepshead, from Florida was randomly divided into two treatment groups: one group was fed soft prey, Mercenaria sp. muscle tissue, and the other group was fed hard prey, Mercenaria sp. in the shell, for 365 days. It was hypothesized that the sheepshead fed hard prey would have a thicker tooth enamel layer containing more calcium, and therefore be stronger than the tooth enamel layer of those fed soft prey …


Winter Microhabitat Foraging Preferences Of Sympatric Boreal And Black-Capped Chickadees In Michigan's Upper Peninsula, Alec R. Lindsay Ph. D., Zach G. Gayk Dec 2012

Winter Microhabitat Foraging Preferences Of Sympatric Boreal And Black-Capped Chickadees In Michigan's Upper Peninsula, Alec R. Lindsay Ph. D., Zach G. Gayk

Faculty Works

We examined differences in microhab- itat use between Boreal (Poecile hudsonicus) and Black- capped chickadees (P. atricapillus) where they co-occur near Marquette, Michigan, USA. Twenty-four Boreal and 37 Black-capped chickadees were followed during 60 hrs of field observation. Boreal Chickadees foraged only in three conifer species, 76% of which were black spruce (Picea mariana), while Black-capped Chickadees foraged widely across six coniferous and three deciduous tree species. Analysis of foraging data categorized by zones within conifer trees indicated high niche overlap (0.676) between Boreal and Black-capped chickadees across all foraging zones. Individual comparisons on a zone-by-zone basis revealed a significant …


Terrestrial And Semi-Aquatic Vertebrates In Diets Of Largemouth Bass In Central Nebraska, Seth A. Lundgren, Keith Geluso, Casey W. Schoenebeck Dec 2012

Terrestrial And Semi-Aquatic Vertebrates In Diets Of Largemouth Bass In Central Nebraska, Seth A. Lundgren, Keith Geluso, Casey W. Schoenebeck

The Prairie Naturalist

Largemouth bass (Micropterus salmoides) are opportunistic predators often feeding in littoral areas during crepuscular periods (Snow 1971). Adult largemouth bass primarily are piscivorous, whereas juveniles generally consume zooplankton, insects, and small fish (Zweiacker and Summerfelt 1974, Carlander 1977, Post 2003). Age-0 largemouth bass generally consume zooplankton and macroinvertebrates (Keast and Webb 1966, Keast 1985, Phillips et al. 1995, Post 2003) and shift to piscivory at 50-70 mm in length (Phillips et al. 1995, Olson 1996, Post 2003). Few studies have documented detailed accounts of other vertebrates besides fish in diets of largemouth bass, which include amphibians (Hodgson and …


The Fall Of "Augustinian Adam": Original Fragility And Supralapsarian Purpose, John Schneider Dec 2012

The Fall Of "Augustinian Adam": Original Fragility And Supralapsarian Purpose, John Schneider

University Faculty Publications and Creative Works

This essay is framed by conflict between Christianity and Darwinian science over the history of the world and the nature of original human personhood. Evolutionary science narrates a long prehuman geological and biological history filled with vast amounts, kinds, and distributions of apparently random brutal and pointless suffering. It has also unveiled an original human person with animal psychosomatic heredity. This narrative seems to discredit Christianity's (Augustinian) metanarrative of the Fall-Paradise Lost and Paradise Regained. The author contends that the Augustinian story and its character of Adam are implausible, anyway, for reasons of theology and apologetics. He proposes that Christians …


An Analysis Of Human Disturbance To Rocky Intertidal Communities Of San Luis Obispo County, Grant Tyler Waltz Dec 2012

An Analysis Of Human Disturbance To Rocky Intertidal Communities Of San Luis Obispo County, Grant Tyler Waltz

Master's Theses

ABSTRACT

An Analysis Of Human Disturbance To Rocky Intertidal Communities Of San Luis Obispo County

Grant Tyler Waltz

The number of coastal areas open to public access in California and San Luis Obispo County is increasing due to the acquisition by California State Parks of land previously owned by private entities. For example, California State Parks acquired property from the Hearst Corporation in 2005, which included 18 miles of coastline. California State Parks is responsible for providing public access in these newly acquired areas and also for maintaining the health of the natural systems found on these properties. Part of …


Effects Of Slash Pile Burning After Restoring Conifer- Encroached Aspen, Christa M. Dagley, John-Pascal Berrill, Stephanie Coppeto, Kyle Jacobson Dec 2012

Effects Of Slash Pile Burning After Restoring Conifer- Encroached Aspen, Christa M. Dagley, John-Pascal Berrill, Stephanie Coppeto, Kyle Jacobson

Aspen Bibliography

Removal of conifers encroaching aspen stands has been advocated and is being practiced in the Lake Tahoe Basin (EIP Project #10080: Aspen Community Restoration Projects). In remote and roadless areas, thinning of conifers is generating large volumes of wood and pile burning is currently being implemented to handle this biomass on site. However, the effects of pile burning on aspen are unknown, and there is an urgent need for guidelines to support design of thinning treatment prescriptions; specifically burn pile size and safe distances from live aspen trees of any size to prevent injury.


Why Snails? How Gastropods Improve Our Understanding Of Ecological Disturbance, Christopher P. Bloch Dec 2012

Why Snails? How Gastropods Improve Our Understanding Of Ecological Disturbance, Christopher P. Bloch

Bridgewater Review

The concept of equilibrium - the idea that a perturbed system will tend to return to its original state - is the basis for many foundational theories in ecology. Yet, the spatial and temporal dynamics of ecosystems are strongly influenced by disturbance. If a particular disturbance greatly alters local climatic conditions, gastropods should be among the first organisms to show a measurable response. The effects of human alteration of habitats (for example, conversion of forest to agriculture) have much longer-lasting effects than those of natural disturbances.


Ghost Tiger Beetle (Cicindela Lepida): Species Conservation Assessment, Melissa J. Panella Dec 2012

Ghost Tiger Beetle (Cicindela Lepida): Species Conservation Assessment, Melissa J. Panella

Nebraska Game and Parks Commission: Publications

The primary goal in development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding the conservation of species of interest. The Nebraska Natural Legacy Project recognizes the ghost tiger beetle, a.k.a. white tiger beetle, (Cicindela lepida) as a Tier I at-risk species of high conservation priority. Some general management recommendations are made here regarding ghost tiger beetles; however, conservation practitioners will need to use professional judgment to make specific management decisions based on objectives, location, and a multitude of variables. This resource was designed to share available knowledge …


Population Characteristics, Development Of A Predictive Population Viability Model, And Catch Dynamics For Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen Dec 2012

Population Characteristics, Development Of A Predictive Population Viability Model, And Catch Dynamics For Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen

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

Population characteristics and long-term population trends of pallid sturgeon Scaphirhynchus albus in the lower Missouri River are relatively unknown. As recovery efforts continue, understanding and quantifying these characteristics and trends are critical for species recovery and future management decisions. Therefore, the objectives of this study were to determine the pallid sturgeon population characteristics, predict changes to the pallid sturgeon population based on different management and life history scenarios, and examine trot line catch dynamics in the lower Missouri River. Catch rates for pallid sturgeon collected with gill nets did not significantly change while catch rates using trot lines significantly declined …


Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine Dec 2012

Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are sensitive to anthropogenic disturbances. Natural recovery takes many years. Active restoration decreases recovery time. Native BSC inocula, which included lichens and mosses, salvaged from gypsiferous soil habitats in Lake Mead National Recreation Area (LMNRA) in the eastern Mojave Desert were stored dry for two years and applied to disturbed soil after a road reconstruction in LMNRA and also used in laboratory experiments to test inoculation technique effectiveness. After 18 months, field results revealed positive relationships between inoculation and the presence of macroscopic BSC cover, cyanobacteria abundance, soil stability, and ammonium concentrations. Chlorophyll fluorescence monitoring of …


The Abundance And Distribution Pattern Of Quagga Mussels In The Las Vegas Bay Of Lake Mead, Nevada And Potential Correlation With Environmental Parameters, Scott Rainville Dec 2012

The Abundance And Distribution Pattern Of Quagga Mussels In The Las Vegas Bay Of Lake Mead, Nevada And Potential Correlation With Environmental Parameters, Scott Rainville

UNLV Theses, Dissertations, Professional Papers, and Capstones

The non-native quagga mussel [Dreissena bugensis (Andrusov, 1897)] was initially discovered in Boulder Basin of Lake Mead, Nevada-Arizona on January 6, 2007. This occurrence marked the first biological invasion of dreissenid mussels in the Western U.S., following a significant North American range expansion of invasive quagga mussels from populations that invaded and colonized the Great Lakes Region in the Northeastern U.S. during 1991. This nonindigenous mollusk species quickly spread from Boulder Basin and became established throughout the entire reservoir by the end of 2007, with the exception of the inner Las Vegas Bay. There was an apparent absence of settled …


Intraspecific Density Dependence And A Guild Of Consumers Coexisting On One Resource, Mark A. Mcpeek Dec 2012

Intraspecific Density Dependence And A Guild Of Consumers Coexisting On One Resource, Mark A. Mcpeek

Dartmouth Scholarship

The importance of negative intraspecific density dependence to promoting species coexistence in a community is well accepted. However, such mechanisms are typically omitted from more explicit models of community dynamics. Here I analyze a variation of the Rosenzweig-MacArthur consumer–resource model that includes negative intraspecific density dependence for consumers to explore its effect on the coexistence of multiple consumers feeding on a single resource. This analysis demonstrates that a guild of multiple consumers can easily coexist on a single resource if each limits its own abundance to some degree, and stronger intraspecific density dependence permits a wider variety of consumers to …


Molecular Phylogeny Of Microhylid Frogs (Anura: Microhylidae) With Emphasis On Relationships Among New World Genera, Rafael O. De Sá, Jeffrey W. Streicher, Relebohile Sekonyela, Mauricio C. Forlani, Simon P. Loader, Eli Greenbaum, Stephen Richards, Célio F.B. Haddad Dec 2012

Molecular Phylogeny Of Microhylid Frogs (Anura: Microhylidae) With Emphasis On Relationships Among New World Genera, Rafael O. De Sá, Jeffrey W. Streicher, Relebohile Sekonyela, Mauricio C. Forlani, Simon P. Loader, Eli Greenbaum, Stephen Richards, Célio F.B. Haddad

Biology Faculty Publications

Background: Over the last ten years we have seen great efforts focused on revising amphibian systematics. Phylogenetic reconstructions derived from DNA sequence data have played a central role in these revisionary studies but have typically under-sampled the diverse frog family Microhylidae. Here, we present a detailed phylogenetic study focused on expanding previous hypotheses of relationships within this cosmopolitan family. Specifically, we placed an emphasis on assessing relationships among New World genera and those taxa with uncertain phylogenetic affinities (i.e., incertae sedis).

Results: One mitochondrial and three nuclear genes (about 2.8 kb) were sequenced to assess phylogenetic relationships. We utilized an …


Gene Duplication And The Evolution Of Hemoglobin Isoform Differentiation In Birds, Michael T. Grispo Dec 2012

Gene Duplication And The Evolution Of Hemoglobin Isoform Differentiation In Birds, Michael T. Grispo

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

The majority of bird species co-express two functionally distinct hemoglobin (Hb) isoforms in definitive erythrocytes: HbA (the major adult Hb isoform, with α-chain subunits encoded by the αA-globin gene) and HbD (the minor adult Hb isoform, with α-chain subunits encoded by the αD-globin gene). The αD-globin gene originated via tandem duplication of an embryonic α-like globin gene in the stem lineage of tetrapod vertebrates, which suggests the possibility that functional differentiation between the HbA and HbD isoforms may be attributable to a retained ancestral character state in HbD that harkens back to a primordial, …