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2015

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Articles 181 - 210 of 777

Full-Text Articles in Ecology and Evolutionary Biology

Wildfire Disturbance And Productivity As Drivers Of Plant Species Diversity Across Spatial Scales, Laura A. Burkle, Jonathan A. Myers, R Travis Belote Oct 2015

Wildfire Disturbance And Productivity As Drivers Of Plant Species Diversity Across Spatial Scales, Laura A. Burkle, Jonathan A. Myers, R Travis Belote

Biology Faculty Research

Wildfires influence many temperate terrestrial ecosystems worldwide. Historical environmental heterogeneity created by wildfires has been altered by human activities and will be impacted by future climate change. Our ability to predict the impact of wildfire-created heterogeneity on biodiversity is limited because few studies have investigated variation in community composition (beta-diversity) in response to fire. Wildfires may influence beta-diversity through several ecological mechanisms. First, high-severity fires may decrease beta-diversity by homogenizing species composition when they create landscapes dominated by disturbance-tolerant or rapidly colonizing species. In contrast, mixed-severity fires may increase beta-diversity by creating mosaic landscapes containing habitats that support species with …


Bleaching, Disease, And Colonization: The Ecology Of Coral Health In Southeastern Nosy Be, Madagascar, Luella Allen-Waller Oct 2015

Bleaching, Disease, And Colonization: The Ecology Of Coral Health In Southeastern Nosy Be, Madagascar, Luella Allen-Waller

Independent Study Project (ISP) Collection

Coral reefs constitute irreplaceable networks of marine biodiversity as well as an important economic resource to many coastal communities in the tropics. Many factors threaten these fragile ecosystems worldwide: overfishing, pollution, ocean acidification, and increasing sea temperatures all interact to diminish reef-building coral health in a variety of ways. This study aims to characterize the taxonomic and spatial patterns of several acute negative health conditions affecting hard corals in and near Lokobe National Park, Nosy Be, Madagascar. Bleaching, coral disease, filamentous algal overgrowth, and soft coral colonization were surveyed at six fringing reef sites representing different ecological zones. While Acropora …


Abejas Silvestres (Himenóptera: Apoidea) En La Neblina: Análisis De La Diversidad, Interacciones, Y Potencial Para Miel En Un Remanente De Bosque Nublado, Jen Hayes Oct 2015

Abejas Silvestres (Himenóptera: Apoidea) En La Neblina: Análisis De La Diversidad, Interacciones, Y Potencial Para Miel En Un Remanente De Bosque Nublado, Jen Hayes

Independent Study Project (ISP) Collection

Las abejas (Himenóptera: Apoidea) se encuentran en casi cada una de las bioregiones en el mundo. Su composición es muy diversa en los neotrópicos. Las abejas silvestres (no-Apis) representan casi el 90% de las especies de abejas en todo el mundo (Parra, 2005). Los objetivos principales de este estudio fueron realizar un inventario de las especies de abejas al final de la estación seca, observar sus interacciones intra-específicas, y determinar el potencial de producción de miel medicinal de las abejas sin aguijón (Apidae: Meliponini). El estudio fue realizado en la Reserva Inti Llacta, un remanente de bosque nublado …


Assessment Of Coral Health And Fish Diversity In The Fringing Reefs Of Porvenir Island And Korbisky Island, Guna Yala, Panama, Emily Waddell Oct 2015

Assessment Of Coral Health And Fish Diversity In The Fringing Reefs Of Porvenir Island And Korbisky Island, Guna Yala, Panama, Emily Waddell

Independent Study Project (ISP) Collection

Coral reefs are the most diverse and productive ecosystems on Earth, serving as important habitats to millions of organisms; however, they are disappearing at alarming rates. The major influences causing their decline are the combined effects of global climate change and increased industrialization, urbanization, and agriculture. Previous studies have correlated high coral coverage with high fish diversity; therefore, as coral reefs disappear, so too does fish diversity. This study assesses the health of the fringe reefs of Porvenir Island and Korbisky Island in Guna Yala, Panama by recording the live coral, bleached coral, diseased coral, and algae cover of each …


Temporal Variability And Cooperative Breeding: Testing The Bet-Hedging Hypothesis In The Acorn Woodpecker, Walter D. Koenig, Eric L. Walters Oct 2015

Temporal Variability And Cooperative Breeding: Testing The Bet-Hedging Hypothesis In The Acorn Woodpecker, Walter D. Koenig, Eric L. Walters

Biological Sciences Faculty Publications

Cooperative breeding is generally considered an adaptation to ecological constraints on dispersal and independent breeding, usually due to limited breeding opportunities. Although benefits of cooperative breeding are typically thought of in terms of increased mean reproductive success, it has recently been proposed that this phenomenonmay be a bet-hedging strategy that reduces variance in reproductive success (fecundity variance) inpopulations living inhighly variable environments. We tested this hypothesis using long-term data on the polygynandrous acorn woodpecker (Melanerpes formicivorus). In general, fecundity variance decreased with increasing sociality, at least when controlling for annual variation in ecological conditions. Nonetheless, decreased fecundity variance …


Effects Of Supplemental Hydration On Physiology And Behavior Of Northern Pacific Rattlesnakes (Crotalus Oreganus Oreganus), Griffin D. Capehart Oct 2015

Effects Of Supplemental Hydration On Physiology And Behavior Of Northern Pacific Rattlesnakes (Crotalus Oreganus Oreganus), Griffin D. Capehart

Master's Theses

Hydration is a critical element for many physiological processes in vertebrates, such as protein production, innate immunity, and behavioral processes such as daily activity and thermoregulation. Few studies have directly assessed the effect of hydration on these animals in nature. While it seems intuitive that drought is stressful to animals, studies examining drought are typically observational and fail to assess how the hydration state of these animals influences their physiology and behavior. We tested for an effect of hydration on several physiological and behavioral parameters in Northern Pacific rattlesnakes (Crotalus oreganus oreganus) by experimentally manipulating hydration levels in …


The Effects Of Urbanization On Tick Parasitism Rates In Birds Of Southeastern Virginia, Erin Leigh Heller Oct 2015

The Effects Of Urbanization On Tick Parasitism Rates In Birds Of Southeastern Virginia, Erin Leigh Heller

Biological Sciences Theses & Dissertations

The coastal region of southeastern Virginia is one of the largest urban areas along one of North America’s migratory flyways. Because hundreds of avian species use this flyway, understanding factors affecting birds and their health is of paramount concern. Within this region, 14 species of ticks have been documented, all of which may serve as vectors of mammal (including human) pathogens. By sampling birds at sites of varying levels of urbanization within the coastal southeastern urban matrix, I studied the relationship between ticks and their avian hosts, and how this relationship varies seasonally. Mistnets were set-up at five permanent sites …


Wildlife Crime And Other Challenges To Resource System Resilience, Patricia Anne Raxter Oct 2015

Wildlife Crime And Other Challenges To Resource System Resilience, Patricia Anne Raxter

Graduate Program in International Studies Theses & Dissertations

Although wildlife crime has exploded in Africa over the past decade —“commercial poaching” now kills an estimated eight percent of the continent’s elephant population each year—some governments have proven more successful than others at protecting wildlife and preserving habitats. To explain this variation, this study examines how the policies of three states (Kenya, Tanzania, and Botswana) have enhanced or undermined the resilience of the continent’s elephant ecosystem. Using the social-ecological system framework, the study illustrates how each state’s changing practices have either exacerbated the stresses wrought by wildlife crime or successfully protected local populations from poaching. The study finds that …


Evolutionary And Ecological Characterization Of Mayaro Virus Strains Isolated During An Outbreak, Venezuela, 2010, Albert J. Auguste, Jonathan Liria, Naomi L. Forrester, Dileyvic Giambalvo, Moncada Maria, Kanya C. Long, Dulce Morón, Nuris De Manzione, Robert B. Tesh, Eric S. Halsey, Tadeusz J. Kochel, Rosa Hernandez, Juan-Carlos Navarro, Scott C. Weaver Oct 2015

Evolutionary And Ecological Characterization Of Mayaro Virus Strains Isolated During An Outbreak, Venezuela, 2010, Albert J. Auguste, Jonathan Liria, Naomi L. Forrester, Dileyvic Giambalvo, Moncada Maria, Kanya C. Long, Dulce Morón, Nuris De Manzione, Robert B. Tesh, Eric S. Halsey, Tadeusz J. Kochel, Rosa Hernandez, Juan-Carlos Navarro, Scott C. Weaver

Faculty Publications

In 2010, an outbreak of febrile illness with arthralgic manifestations was detected at La Estación village, Portuguesa State, Venezuela. The etiologic agent was determined to be Mayaro virus (MAYV), a reemerging South American alphavirus. A total of 77 cases was reported and 19 were confirmed as seropositive. MAYV was isolated from acute-phase serum samples from 6 symptomatic patients. We sequenced 27 complete genomes representing the full spectrum of MAYV genetic diversity, which facilitated detection of a new genotype, designated N. Phylogenetic analysis of genomic sequences indicated that etiologic strains from Venezuela belong to genotype D. Results indicate that MAYV is …


Jane Claire Dirks's Correspondence With Stanley G. Jewett, Jane Claire Dirks-Edmunds, Stanley G. Jewett Sep 2015

Jane Claire Dirks's Correspondence With Stanley G. Jewett, Jane Claire Dirks-Edmunds, Stanley G. Jewett

Jane Claire Dirks-Edmunds Documents

This exchange between Jane Claire Dirks (later Jane Claire Dirks-Edmunds) and Stanley G. Jewett, a biologist with Region 1 of the Fish and Wildlife Service (serving Oregon and five other states), is an example of the type of correspondence Dirks had with various experts on the Pacific forest region while she was completing her doctoral thesis. Dirks-Edmunds began to study Zoology in Illinois immediately after earning her Bachelor's degree in Biology from Linfield College in 1937. She returned to teach in the Biology department at Linfield from 1941-1974.


Plant Index Card For Rubus Parviflorus,Western Thimbleberry, Jane Claire Dirks-Edmunds Sep 2015

Plant Index Card For Rubus Parviflorus,Western Thimbleberry, Jane Claire Dirks-Edmunds

Jane Claire Dirks-Edmunds Documents

This is one example of a research card used by Dr. Jane Claire Dirks-Edmunds. Dirks-Edmunds used these cards to catalog the plants, animals, and insects at her Saddleback Mountain research site during the 1950s. This card has notes on Rubus parviflorus (thimbleberry) a part of the Rosaceae (rose) family.


Jane Claire Dirks-Edmunds's Notes On Lake Atitlán, Guatemala, Jane Claire Dirks-Edmunds Sep 2015

Jane Claire Dirks-Edmunds's Notes On Lake Atitlán, Guatemala, Jane Claire Dirks-Edmunds

Jane Claire Dirks-Edmunds Documents

This document includes typed and handwritten notes from Dr. Jane Claire Dirks-Edmunds about Lake Atitlán, a large body of water in Guatemala surrounded by three volcanoes. During the 1970s, Dirks-Edmunds conducted research with others on various aspects of the inland Guatemalan system.


Advertisement For Trapper Nelson's Indian Pack Boards, Charles Trager Sep 2015

Advertisement For Trapper Nelson's Indian Pack Boards, Charles Trager

Jane Claire Dirks-Edmunds Documents

This advertisement shows the type of hiking materials that were popular before the advent of plastics and polymers. In her book Not Just Trees, Dr. Jane Claire Dirks-Edmunds writes about the texture of the cloth and materials she used during fieldwork on Saddleback Mountain in her early research with Dr. James A. Macnab at Linfield College. Dirks-Edmunds, a 1937 graduate of Linfield, graduated from the University of Illinois in 1941; she returned to teach in the Biology department at Linfield from 1941-1974.


Whole-Genome Sequencing Of Kshv From Zambian Kaposi’S Sarcoma Biopsies Reveals Unique Viral Diversity, Landon N. Olp, Adrien Jeanniard, Clemence Marimo, John T. West, Charles Wood Sep 2015

Whole-Genome Sequencing Of Kshv From Zambian Kaposi’S Sarcoma Biopsies Reveals Unique Viral Diversity, Landon N. Olp, Adrien Jeanniard, Clemence Marimo, John T. West, Charles Wood

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the etiological agent for Kaposi’s sarcoma (KS). Both KSHV and KS are endemic in sub-Saharan Africa where approximately 84% of global KS cases occur. Nevertheless, whole-genome sequencing of KSHV has only been completed using isolates from Western countries—where KS is not endemic. The lack of whole-genome KSHV sequence data from the most clinically important geographical region, sub-Saharan Africa, represents an important gap as it remains unclear whether genomic diversity has a role on KSHV pathogenesis. We hypothesized that distinct KSHV genotypes might be present in sub-Saharan Africa compared to Western countries. Using a KSHV-targeted enrichment …


Book Reviews, Robert D. Aldridge, Michael B. Thompson, Malorie M. Hayes, Rafael O. De Sá, Christopher G. Lowe Sep 2015

Book Reviews, Robert D. Aldridge, Michael B. Thompson, Malorie M. Hayes, Rafael O. De Sá, Christopher G. Lowe

Biology Faculty Publications

Reproductive Biology and Phylogeny of Lizards and Tuatara. J. L. Rheubert, D. S. Siegel, and S. E. Trauth (Eds.). 2014. CRC Press. ISBN 9781466579866. 760 p. $143.96 (hardcover).—

According to the authors, this book was intended to summarize the current knowledge of phylo- geny and reproduction of the Lepidosauria. I believe the authors have achieved their goal. Many of the chapters in this book are derived from presentations that took place at the Symposium on Reproductive Biology of Lizards at the Joint Meeting of Ichthyologists and Herpetologists held in Chattanooga, Tennessee in 2014. Although the majority of the authors are …


Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee R. Berger, John Hawks, Darryl J. De Ruiter, Steven E. Churchill, Peter Schmid, Lucas K. Delezene, Tracy L. Kivell, Heather M. Garvin, Scott A. Williams, Jeremy M. Desilva, Matthew M. Skinner, Charles M. Musiba, Noel Cameron, Trenton W. Holliday, William Harcourt-Smith, Et Al. Sep 2015

Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee R. Berger, John Hawks, Darryl J. De Ruiter, Steven E. Churchill, Peter Schmid, Lucas K. Delezene, Tracy L. Kivell, Heather M. Garvin, Scott A. Williams, Jeremy M. Desilva, Matthew M. Skinner, Charles M. Musiba, Noel Cameron, Trenton W. Holliday, William Harcourt-Smith, Et Al.

Publications and Research

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike foot and lower …


Ecoscience + Art Initiative: Designing A New Paradigm For College Education, Scholarship, And Service, Changwoo Ahn Sep 2015

Ecoscience + Art Initiative: Designing A New Paradigm For College Education, Scholarship, And Service, Changwoo Ahn

The Transdisciplinary STEAM+ Journal

The paper presents a new initiative, EcoScience + Art, which blooms at George Mason University. The creator explains the background, history, and recent activities of the initiative, and also introduces an on-going special project called “The Rain Project”, a student participatory project to design, construct, and monitor a green infrastructure (i.e., floating wetland) for sustainable stormwater management on campus. The special project is geared to design and present a new paradigm to integrate college education, scholarship, and service. The relevance of the initiative and the special project to STEAM education is discussed.


A Generalist Brood Parasite Modifies Use Of A Host In Response To Reproductive Success, Matthew I M Louder, Wendy M. Schelsky, Amber N. Albores, Jeffrey P. Hoover Sep 2015

A Generalist Brood Parasite Modifies Use Of A Host In Response To Reproductive Success, Matthew I M Louder, Wendy M. Schelsky, Amber N. Albores, Jeffrey P. Hoover

Publications and Research

Avian obligate brood parasites, which rely solely on hosts to raise their young, should choose the highest quality hosts to maximize reproductive output. Brown-headed cowbirds (Molothrus ater) are extreme host generalists, yet female cowbirds could use information based on past reproductive outcomes to make egg-laying decisions thus minimizing fitness costs associated with parasitizing low quality hosts. We use a long-term (21 years) nest box study of a single host, the prothonotary warbler (Protonotaria citrea), to show that local cowbird reproductive success, but not host reproductive success, was positively correlated with the probability of parasitism the following …


Natural Gardening, Lisa Karen Miller Sep 2015

Natural Gardening, Lisa Karen Miller

DLPS Faculty Publications

This presentation features methods of natural and organic gardening that preclude the use of harmful pesticides and herbicides.


Response Of Mammalian Macrophages To Challenge With The Chlorovirus Atcv-1, Thomas M. Petro, Irina V. Agarkova, You Zhou, Robert H. Yolken, James L. Van Etten, David D. Dunigan Sep 2015

Response Of Mammalian Macrophages To Challenge With The Chlorovirus Atcv-1, Thomas M. Petro, Irina V. Agarkova, You Zhou, Robert H. Yolken, James L. Van Etten, David D. Dunigan

Nebraska Center for Virology: Faculty Publications

It was recently reported that 44% of healthy humans in a study cohort had DNA sequences similar to Chlorovirus ATCV-1 (family Phycodnaviridae) in oropharyngeal samples and had decreases in visual processing and visual motor speed compared with individuals in whom no virus was detected. Moreover, mice inoculated orally with ATCV-1 developed immune responses to ATCV-1 proteins and had decreases in certain cognitive domains. Because heightened IL-6, nitric oxide (NO), and ERK MAP kinase activation from macrophages are linked to cognitive impairments, we evaluated cellular responses and viral plaque forming units in murine RAW264.7 and primary macrophages after exposure to …


Community Involvement To Address A Long-Standing Invasive Species Problem: Aspects Of Civic Ecology In Practice, Rebecca W. Dolan, Kelly Harris, Mark Adler Sep 2015

Community Involvement To Address A Long-Standing Invasive Species Problem: Aspects Of Civic Ecology In Practice, Rebecca W. Dolan, Kelly Harris, Mark Adler

Scholarship and Professional Work - LAS

Invasive non-native species (INS) are found in every city around the globe, but their impacts in urban settings as biological agents of visual pollution that block views of natural landscapes and disconnect citizens from nature are not as often addressed as comprehensively as their impacts in natural areas or agricultural settings. The multiple impacts of INS in cities make them ideal candidates for aspects of Civic Ecology Practice, where local environmental stewardship action is taken to enhance green infrastructure and community well-being in urban and other human-dominated systems. We present details of a community driven program focused on removal of …


Spreading Holiday Spirit And Northwestern Salamanders, Ambystoma Gracile (Baird 1859) (Caudata: Ambystomatidae), Across The Usa, Michael R. Rochford, Jeffrey M. Lemm, Kenneth Krysko, Louis A. Somma, Robert W. Hansen, Frank J. Mazzotti Sep 2015

Spreading Holiday Spirit And Northwestern Salamanders, Ambystoma Gracile (Baird 1859) (Caudata: Ambystomatidae), Across The Usa, Michael R. Rochford, Jeffrey M. Lemm, Kenneth Krysko, Louis A. Somma, Robert W. Hansen, Frank J. Mazzotti

Papers in Herpetology

Introduced species of amphibians and reptiles are of growing conservation concern (Bury and Luckenbach 1976; Krysko et al. 2011; Meshaka 2011). Unintentional introductions result largely from individuals escaping from enclosures or hitch-hiking in cargo or on vehicles, whereas intentional introductions occur primarily because a species is perceived to be of value to humans or from deliberately releasing sick or unwanted animals, including pets (Kraus 2009; Krysko et al. 2011). In Florida, most known introductions are directly related to the pet trade, but about 12% are related to the cargo pathway (Krysko et al. 2011). In this paper, we report the …


Morphological Response In Sister Taxa Of Woodrats (Genus: Neotoma) Across A Zone Of Secondary Contact, Michaela M. Koenig Sep 2015

Morphological Response In Sister Taxa Of Woodrats (Genus: Neotoma) Across A Zone Of Secondary Contact, Michaela M. Koenig

Master's Theses

This study focuses on a secondary contact zone between two sister species of woodrat, Neotoma fuscipes (dusky-footed woodrat) and N. macrotis (big-eared woodrat). Along the Nacimiento River, on the border of southern Monterey and northern San Luis Obispo counties, the ranges of these sister species of woodrats meet and overlap forming a secondary contact zone. The zone of secondary contact is estimated to include a 500-meter (~1,650 linear feet) portion of the Nacimiento River riparian corridor.

This research examines quantifiable morphological change that is likely associated with heightened inter-specific competition within the contact zone. When in sympatry the sister species …


Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing, Heather Lyn Hayden, Elise F. Granek Sep 2015

Coastal Sediment Elevation Change Following Anthropogenic Mangrove Clearing, Heather Lyn Hayden, Elise F. Granek

Environmental Science and Management Faculty Publications and Presentations

Coastal mangrove forests along tropical shorelines serve as an important interface between land and sea. They provide a physical buffer protecting the coastline from erosion and act as sediment “traps” catching terrestrial sediment, thus preventing smothering of subtidal coral reefs. Coastal development that removes mangrove habitat may impact adjacent nearshore coral reefs through sedimentation and nutrient loading. We examined differences in sediment elevation change between patches of open-coast intact and anthropogenically cleared red mangroves (Rhizophora mangle) on the east side of Turneffe Atoll, Belize, to quantify changes following mangrove clearing. Samples were collected over a 24 month period at five …


Climate-Suitable Planting As A Strategy For Maintaining Forest Productivity And Functional Diversity, Matthew Joshua Duveneck, Robert M. Scheller Sep 2015

Climate-Suitable Planting As A Strategy For Maintaining Forest Productivity And Functional Diversity, Matthew Joshua Duveneck, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

Within the time frame of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate-suitable tree species (CSP), those tree species with current or historic distributions immediately south of a focal landscape, to maintain or increase aboveground biomass, productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000–2100) at a 2-ha cell resolution and five-year time steps within …


Current Status Of The Northern Long-Eared Myotis (Myotis Septentrionalis) In Northwestern Nebraska, Keith Geluso, Patricia Freeman, Cliff Lemen Sep 2015

Current Status Of The Northern Long-Eared Myotis (Myotis Septentrionalis) In Northwestern Nebraska, Keith Geluso, Patricia Freeman, Cliff Lemen

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The Northern Long-eared Myotis (Myotis septentrionalis; Order: Chiroptera) occurs in eastern, southern, and northern Nebraska, but its current distribution in northwestern parts of the state is unclear due to its recent arrival to the region. We investigated the status of this species in the Pine Ridge via mist net (2011-2014) and acoustic surveys (2014). We documented nine species of bats in the region, including M. septentrionalis. Of 423 total bats, M. septentrionalis was represented by four individuals, the fewest of all species during our four-year survey. We only documented M. septentrionalis in Sheridan County; …


Grappling With Wicked Problems: Exploring Photovoice As A Decolonizing Methodology In Science Education, Kristin Cook Sep 2015

Grappling With Wicked Problems: Exploring Photovoice As A Decolonizing Methodology In Science Education, Kristin Cook

Graduate Theses, Dissertations, and Capstones

This abstract is going to tell you what this article is about.


How Are Rare Species Maintained?: Reproductive Barriers Between Layia Jonesii, A Rare Serpentine Endemic, And L. Platyglossa, Natalie L. Rossington Sep 2015

How Are Rare Species Maintained?: Reproductive Barriers Between Layia Jonesii, A Rare Serpentine Endemic, And L. Platyglossa, Natalie L. Rossington

Master's Theses

Reproductive barriers are vital to generating new species as well as maintaining distinct species. Investigating reproductive barriers between closely related plant taxa helps us to understand how these barriers are maintained, particularly between rare and widespread relatives. Layia jonesii, a rare San Luis Obispo County serpentine endemic, and L. platyglossa, a common coastal species, co-occur on serpentine derived hillsides and are interfertile. At these locations, L. jonesii is isolated to dry soils near serpentine rock outcrops and L. platyglossa is located on slightly deeper grassland soils surrounding the rock outcrops. On hillsides where they co-occur, I observe two morphologically …


An Exploration Of The Phylogenetic Placement Of Recently Discovered Ultrasmall Archaeal Lineages, Jeffrey M. O'Brien Aug 2015

An Exploration Of The Phylogenetic Placement Of Recently Discovered Ultrasmall Archaeal Lineages, Jeffrey M. O'Brien

Honors Scholar Theses

In recent years, several new clades within the domain Achaea have been discovered. This is due in part to microbiological sampling of novel environments, and the increasing ability to detect and sequence uncultivable organisms through metagenomic analysis. These organisms share certain features, such as small cell size and streamlined genomes. Reduction in genome size can present difficulties to phylogenetic reconstruction programs. Since there is less genetic data to work with, these organisms often have missing genes in concatenated multiple sequence alignments. Evolutionary Biologists have not reached a consensus on the placement of these lineages in the archaeal evolutionary tree. There …


Disturbance Alters Beta-Diversity But Not The Relative Importance Of Community Assembly Mechanisms, Jonathan A. Myers, Jonathan M. Chase, Raelene M. Crandall, Iván Jiménez Aug 2015

Disturbance Alters Beta-Diversity But Not The Relative Importance Of Community Assembly Mechanisms, Jonathan A. Myers, Jonathan M. Chase, Raelene M. Crandall, Iván Jiménez

Biology Faculty Research

  1. Ecological disturbances are often hypothesized to alter community assembly processes that influence variation in community composition (β-diversity). Disturbance can cause convergence in community composition (low β-diversity) by increasing niche selection of disturbance-tolerant species. Alternatively, disturbance can cause divergence in community composition (high β-diversity) by increasing habitat filtering across environmental gradients. However, because disturbance may also influence β-diversity through random sampling effects owing to changes in the number of individuals in local communities (community size) or abundances in the regional species pool, observed patterns of β-diversity alone cannot be used to unambiguously discern the relative importance of community assembly mechanisms.
  2. We …