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Divergence In Life History Traits Between Two Populations Of A Seed-Dimorphic Halophyte In Response To Soil Salinity, Fan Yang, Jerry M. Baskin, Carol C. Baskin, Xuejun Yang, Dechang Cao, Zhenying Huang

Biology Faculty Publications

Production of heteromorphic seeds is common in halophytes growing in arid environments with strong spatial and temporal heterogeneity. However, evidence for geographic variation (reflecting local adaptation) is almost nonexistent. Our primary aims were to compare the life history traits of two desert populations of this halophytic summer annual Suaeda corniculata subsp. mongolica and to investigate the phenotypic response of its plant and heteromorphic seeds to different levels of salt stress. Dimorphic seeds (F₁) of the halophyte S. corniculata collected from two distant populations (F₀) that differ in soil salinity were grown in a common environment under …

Mitigating The Conflict Between Pitfall-Trap Sampling And Conservation Of Terrestrial Subterranean Communities In Caves, Peter Kozel, Tanja Pipan, Nina Šajna, Slavko Polak, Tone Novak

International Journal of Speleology

Subterranean habitats are known for their rich endemic fauna and high vulnerability to disturbance. Many methods and techniques are used to sample the biodiversity of terrestrial invertebrate fauna in caves, among which pitfall trapping remains one of the most frequently used and effective ones. However, this method has turned out to be harmful to subterranean communities if applied inappropriately. Traditionally, pitfall traps have been placed in caves solely on the ground. Here we present an optimized technique of pitfall trapping to achieve a balance between sampling completeness and minimal disturbance of the fauna in the cave. Monthly we placed traps …

Phenology, Habitat Use, And The Impacts Of Wetland Management On Autumn Migrating Rails In Missouri, Auriel M.V. Fournier

Graduate Theses and Dissertations

Rails (Family: Rallidae) are among the least studied birds in North America, in large part due to their elusive nature. As a wetland-dependent species, understanding the timing of their migration and their habitat needs during migration is especially important since management needs to be timed to balance the needs of many species. I developed and verified a new distance sampling based nocturnal ATV spotlight survey because traditional call-broadcast surveys are not effective during autumn migration because of the drop off in call rate after the breeding season. These surveys allow us to ask point-level questions about what habitats rails select …

Heterogeneity Of Avian Breeding Habitat On Grazing Lands Of The Northern Great Plains, Maggi S. Sliwinski

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

Native rangelands in the Great Plains are largely privately owned and used for beef production. Vegetation heterogeneity is important for maintaining biodiversity, but private land may be more homogenous than desired. My research had two components: 1) to examine whether a variety of grazing strategies created vegetation heterogeneity in a large, intact rangeland, and 2) to understand beef producers’ attitudes about vegetation heterogeneity.

First, I sampled vegetation structure, composition, and bird abundance at multiple plots on eleven management units in Cherry County, Nebraska. Units were managed with commonly used grazing strategies (e.g., short-duration grazing and season-long continuous grazing). I examined …

Niche Modeling For The Giant Panda, Ailuropoda Melanoleuca, And The Original Panda, Ailurus Fulgens: Habitat Preferences And Evolutionary Consequences, Lauren M. Lyon

Electronic Theses and Dissertations

The well-known symbol for conservation, the giant panda bear, and the original red panda have been forced into remote habitats due to anthropogenic disturbance, making ecological study difficult. Therefore the first known species distribution model was created to predict the most likely areas of occurrence within the known range of these elusive animals. These models were then projected onto North America and evaluated against existing breeding programs. Additionally, the close proximity of the Gray Fossil Site and the discovery of the most complete fossil red panda specimens in the world allowed ecomorphological comparisons between the modern red panda, Ailurus fulgens …

Cranial Morphological Distinctiveness Between Ursus Arctos And U. Americanus, Benjamin James Hillesheim

Electronic Theses and Dissertations

Despite being separated by millions of years of evolution, black bears (Ursus americanus) and brown bears (Ursus arctos) can be difficult to distinguish based on skeletal and dental material alone. Complicating matters, some Late Pleistocene U. americanus are significantly larger in size than their modern relatives, obscuring the identification of the two bears. In the past, fossil bears have been identified based on differences in dental morphology or size. This study used geometric morphometrics to look at overall differences in cranial shape and used step-wise discriminant analysis to identify specific characters that distinguish cranial morphology between …

Ecological Consequences Of Water Loss Under Climate Change In Small Ectotherms, Eric Alexander Riddell

All Dissertations

Warming climates threaten to reduce biodiversity across the planet, yet the capacity of organisms to minimize the effects of climate change are rarely considered in current ecological predictions of climate change. Organisms can minimize the effect of warming through behavioral, physiological, and morphological processes that limit exposure to lethal conditions or improve performance. Therefore, integrating these mechanisms into ecological models might improve predictions on the loss of biodiversity under climate change. For my dissertation, I focus on the physiological processes that influence habitat suitability in a group of terrestrial, lungless salamanders (Plethodon spp.) found in the core of the global …

Parasitism Of Free-Ranging Neotropical Primates: Examining Parasite-Host And Parasite-Parasite Relationships, Gideon A. Erkenswick

Dissertations

Parasites are infectious agents that require resources from host organisms to complete all or part of their lifecycles. It is customary for wild animals to acquire and maintain multiple parasitic infections during their lifetime. The effects of parasites on hosts vary across demographic and environmental variables, and in relation to each other. Moreover, the propensity for a host animal to acquire an infection can be influenced by other host species in the area that are susceptible to the same parasites. This dissertation describes and explores the natural parasite assemblage of a free-ranging community of nonhuman primates in the Peruvian Amazon …

Abundance And Habitat Preferences Of Introduced Muscovy Ducks (Cairina Moschata), Jacqueline Marie Perry Cahanin

USF Tampa Graduate Theses and Dissertations

Muscovy ducks are native only to Central and South America, Mexico, and parts of southern Texas and are considered invasive in some areas outside of their native range. Although they have been introduced worldwide, they remain largely unstudied. The primary focus of this study was to relate Muscovy duck abundance to habitat characteristics of wetlands in Tampa, Florida. Muscovy abundance was measured using point count methods at 21 wetland sites that occur within an eight km radius of the University of South Florida’s main campus. Habitat features at these sites were assessed using field methods and Geographic Information Systems (GIS) …

Zonation Pattern And Spatial Arrangement Of A Geukensia Granosissima Population In A Mixed Mangrove Forest Of Tampa Bay, Derrick Shane Hudson

USF Tampa Graduate Theses and Dissertations

Here I provide the first report on Geukensia granosissima patterns of abundance along a tidal gradient within a mixed mangrove stand located in Tampa Bay, Florida, USA. Specifically, I examined 1) the relationship between G. granosissima size and density with mangrove root type (e.g. prop root, pneumatophore), and of density within the intertidal zones; and 2) the possible role of predation in shaping the lower zonation patterns displayed. Transect surveys located along the lower and upper population limit boundaries were conducted every two months over a ten-month period. Variables measured include size distribution, density of mussels, above ground mangrove prop …

Road Ecology: Shifting Gears Toward Evolutionary Perspectives, Steven P. Brady, Jonathan L. Richardson

Dartmouth Scholarship

Recent advances in understanding the often rapid pace of evolution are reshaping our view of organisms and their capacity to cope with environmental change. Though evolutionary perspectives have gained traction in many fields of conservation, road ecology is not among them. This is surprising because roads are pervasive landscape features that generate intense natural selection. The biological outcomes from these selection pressures – whether adaptive or maladaptive – can have profound consequences for population persistence. We argue that studying evolutionary responses is critical to accurately understand the impacts of roads. Toward that end, we describe the basic tenets and relevance …

Chapter 2 - Protozoa, Janice M. Glime

Bryophyte Ecology Volume 2: Bryological Interaction

Explore the contents of Bryophyte Ecology, Volume 2, Chapter 2 - Protozoa by clicking the links above. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

Use CTRL+F to easily search within PDF files.

Ebook sponsored by Michigan Technological University and the International Association of Bryologists.

Chapter 13 - Fish, Janice M. Glime

Bryophyte Ecology Volume 2: Bryological Interaction

Explore the contents of Bryophyte Ecology, Volume 2, Chapter 13 - Fish by clicking the link above. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

Use CTRL+F to easily search within PDF files.

Ebook sponsored by Michigan Technological University and the International Association of Bryologists.

Chapter 1 - Introduction, Janice M. Glime

Bryophyte Ecology Volume 1: Physiological Ecology

Explore the contents of Bryophyte Ecology, Volume 1, Chapter 1 - Introduction by clicking the link above. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

Use CTRL+F to easily search within PDF files.

Ebook sponsored by Michigan Technological University and the International Association of Bryologists.

Pteropus Voeltzkowi And The Understory: A Study Of The Behavioral Impacts Of The Pemba Flying Fox On The Vegetation And Soil Quality Of Pemba Island, Lea Davidson

Independent Study Project (ISP) Collection

This study examines the impact of Pteropus voeltzkowi , colloquially known as the Pemba Flying Fox, on biodiversity and health of the forest ground layer. Known to serve as reforesters, high concentrations of both fruit seeds and nutrient dense guano are introduced into specific environmental locations due to the bat's behavioral patterns. Working around two roost locations, one in Ngezi Forest and the other at the Kidike conservation site near Mjini Ole, diversity of juvenile vegetation was measured and quantified. In a laboratory setting, soil samples from both sites were analyzed for impacts of guano concentration on soil chemical properties. …

The Effect Of Site Characteristics On The Reproductive Output Of Lesser Celandine (Ranunculus Ficaria), Justin P. Kermack

ETD Archive

Ranunculus ficaria L., an ephemeral perennial invasive plant brought over from Europe, is becoming widespread throughout the Northeastern United States. This herbaceous buttercup is able to create extensive dense mats that limit native species growth. Taking advantage of an early growing season and rapid reproduction rates, this species can create dense monocultures, which threatens native communities and ecosystems. Elimination of native spring ephemerals results in decreased biodiversity. A better understanding of how R. ficaria responds to site characteristics is needed to prioritize management efforts toward high-risk sites.

Ranunculus ficaria abundance and reproductive output (seed, bulbil and tuber production rates) were …

Climate Dynamics, Invader Fitness, And Ecosystem Resistance In An Invasion-Factor Framework, Stephen L. Young, David R. Clements, Antonio Ditommaso

West Central Research and Extension Center, North Platte

As researchers and land managers increasingly seek to understand plant invasions and the external (climate) and internal (plant genetics) conditions that govern the process, new insight is helping to answer the elusive question of what makes some invasions successful and others not. Plant invasion success or failure is based on a combination of evolutionary and ecological processes. Abiotic (e.g., climate) and biotic (e.g., plant competition) conditions in the environment and plant genetics (e.g., fitness) combine in either decreasing or increasing invasion, yet it has proven challenging to know exactly which of these conditions leads to success for a given species, …

A New Tachinid Genus And Species Record For North America: Iceliopsis Borgmeieri Guimarães, John O. Stireman Iii, Jane E. Dell

Biological Sciences Faculty Publications

The Iceliini are a small, enigmatic New World tribe of Tachininae consisting of three genera, Icelia RobineauDesvoidy, Iceliopsis Guimarães, and Erviopsis Townsend, and five recognized species (Guimarães 1976). All known species are exclusively Neotropical in distribution with the exception of Icelia triquetra (Olivier), which ranges from Brazil, through Central America, and as far north as New York state (O’Hara & Wood 2004). Members of the tribe are generally medium-sized (ca. 7–12 mm), elongate, yellowish or grayish in color, and resemble Dexiini or Leskiini in general appearance. Species of Iceliini are relatively rarely collected and there is but a single host …

Ecology Of Blanchard Springs Caverns, Ozark National Forest, Arkansas: 42 Years Later, C. J. Midden, S. K. Sasser, J. L. Grove

Journal of the Arkansas Academy of Science

Interrelationships between subterranean and epigean environments affect dispersion and distribution of cave organisms among the macro and microhabitats. This study examined the environmental impact of 42 years of tourism and development in the two lower sections of Blanchard Springs Caverns found in Stone County, Arkansas; and contributes to a better understanding of the seasonal fluctuations of the abiotic and biotic parameters.

Temperature, water quality, and fauna data were collected. A new entrance, lighting, and approximately 12,500 visitors during the 12-month study had no observable effect on cavern temperatures. Stream water quality measurements were comparable to Grove’s 1974 study. Gray bat, …

Swift Foxes In Southwestern South Dakota: Assessing The Current Status Of A Reintroduced Population, Sarah Ann Nevison

Electronic Theses and Dissertations

Swift foxes (Vulpes velox) were reintroduced into Badlands National Park between 2003 and 2006 after being nearly extirpated from South Dakota in the early 1900’s. Genetic analysis provided strong evidence that the reintroduction was successful, but viability analysis indicated the population may be in jeopardy with a high probability of extinction. Recently, the population has declined due to various biotic and abiotic factors (e.g., recent weather patterns, effects of plague [Yersinia pestis], and increased coyote [Canis latrans] numbers). No information on the status of swift foxes has been collected since 2009. Between 2014 and 2016, the objectives of this study …

Are Mussel Shells Environmental Dna Time Capsules? A Comparison Of Extraction Methods For Obtaining Dna From Shell Material., Kelsey Elizabeth Rogers

Online Theses and Dissertations

Freshwater mussels have become some of the most imperiled species in North America and widespread populations have succumbed to pollution and many other anthropogenic-related factors. With molecular techniques evolving, a recent interest in ancient DNA and museum specimens has emerged and prompted a study to test the ability of several extraction methods to isolate DNA from museum mussel specimens. The purpose of this study was to determine if four DNA extraction methods had influence on total DNA yield (ng/mg) from mussel tissue. The hinge ligaments of freshwater mussels ranging in collection date (1984-2015) were used as the source of genetic …

Invasion Dynamics Of The Exotic Liana Euonymus Fortunei (Turcz.) Hand.-Mazz. (Wintercreeper), Todd J. Rounsaville

Theses and Dissertations--Biology

Elevated atmospheric CO₂ has been implicated as a driver of increased liana abundance worldwide. Known as disturbance creators and beneficiaries, lianas possess the potential to significantly influence forest ecosystems. I investigated the early-invasion dynamics of Euonymus fortunei (wintercreeper), an evergreen liana that is invading forests in eastern North America, disrupting native plant communities and ecosystem functions.

Wintercreeper is widely cultivated as an ornamental groundcover, frequently invading natural areas via asexual stem growth. Invasion of remote natural areas is dependent upon seed transport and may occur less frequently. I examined the mechanisms of seed dormancy by conducting a ‘move-along’ experiment …

Are Weevils Picky Eaters? Community Structure And Host Specificity Of Neotropical Saproxylic Beetles (Coleoptera: Curculionidae), Jhunior A. Morillo

Dissertations and Theses

Abstract Primary saproxylic beetles play a major role in forest nutrient cycling and making deadwood accessible to other decomposers. Understanding beetle host preferences and patterns of community assembly is critical for their conservation, and for predicting which species might become invasive. This project aims to investigate the ecological and host specificity, as well as the community composition of curculionids in a mosaic of old-growth (OG) and secondary forest on the Osa Peninsula, Costa Rica. The subfamily Scolytinae was expected to be the most species-rich and abundant. Ambrosia beetles were expected to have more generalist species than other curculionids. Old growth …

Grasshopper (Orthoptera: Caelifera) And Plant Community Relationships On Indio Mountains Research Station, Hudspeth County, Texas, Sara Ebrahim Baqla

Open Access Theses & Dissertations

An ecogeographic analysis of a grasshopper survey was conducted at eight sites on Indio Mountains Research Station (IMRS) in the Chihuahuan Desert during September 2014 through December 2015. Five sites contained ephemeral water sources (earthen tanks), one had perennial water (spring system), and two were open desert. A total of 23 grasshopper species were identified, and six of those were new records for the property. The most species rich site was Echo Tank, with 14 grasshopper species. A UPGMA dendrogram showed Red Tank and Rattlesnake Tank, both wetland sites, to be the most similar (CBR = .84). A poisson model …

Population Density, Habitat Dynamic And Aerial Survival Of Relict Cave Bivalves From Genus Congeria In The Dinaric Karst, Olga Jovanović Glavaš, Branko Jalžić, Helena Bilandžija

International Journal of Speleology

Caves are some of the least-known ecosystems on Earth and long-term ecological studies and population size estimates are very rare. Genus Congeria is a Tertiary relict that comprises three species from Dinaric karst area; C. kusceri, C. jalzici and C. mulaomerovici, each with very limited distribution. They are the only known cave bivalves and in contrast to many other cave species, they form populations with high densities. We estimated that the population of C. kusceri in Jama u Predolcu is between 72,454 and 72,906 individuals. The highest density occurred between one and three meters depth, and reached maximum …

Integrating Habitat Suitability Modeling And Radio Telemetry To Describe Habitat Use Of The Western Massasaugas, Sistrurus T. Tergeminus, In Texas, Mitchell R. Barazowski

Biology Theses

Habitat suitability modeling using the software package MaxEnt (Phillips, Anderson, & Schapire, 2006) is a popular method for describing the habitat of rare species. MaxEnt uses “presence only” data to develop models; however presence data are highly skewed towards areas of high detection probability and these areas may not represent the full range of habitat use. Thusly, predictions from models developed using only data from areas with high detection probability may not represent all suitable habitat. This study tested the ability of MaxEnt models developed using three different data sets to accurately describe Western Massasauga (Sistrurus t. tergeminus) habitat at …

Territoriality And Spatial Structure In The Green Anole, Anolis Carolinensis, William D. Weber Jr.

LSU New Orleans Theses and Dissertations

Anolis carolinensis has been a model organism for ecology and evolutionary biology since the seventies, yet there are still understudied aspects of their ecology. A five-year study has provided microsatellite genotypes to be used in building a pedigree and assess relatedness, enabling us to evaluate the spatial distribution of an urban population of A. carolinensis. Results indicate no correlation between a male’s size and the distance others keep from it; however, males belonging in the heavyweight morph are dictating the spatial distribution in this population. In addition, juvenile dispersal of male offspring and partial philopatry of female offspring are …

Phylogenetics, Biogeography, And Climate Niche Variation Of South Pacific And Hawaiian Psychotria, Elaine Zhang

Master's Theses

Why do some species have broad geographic distributions, while other species are confined to a narrow distribution? Species age, ecological niche, or dispersal traits may help explain why some insular species are abundant and found on many islands, while others are rare and restricted to one island. In this study, I inferred a robust, time-calibrated phylogeny of the Hawaiian Psychotria, using two nuclear and eight chloroplast loci, sampling 67 individuals. I coupled my phylogenetic hypothesis with climatic data, ecological niche modeling, and morphological dispersal characteristics to explain the variation in number of islands occupied by each species. My inferred phylogeny …

Where And How Wolves (Canis Lupus) Kill Beavers (Castor Canadensis), Thomas Gable, Steve K. Windels, John G. Bruggink, Austin T. Homkes

Journal Articles

Beavers (Castor canadensis) can be a significant prey item for wolves (Canis lupus) in boreal ecosystems due to their abundance and vulnerability on land. How wolves hunt beavers in these systems is largely unknown, however, because observing predation is challenging. We inferred how wolves hunt beavers by identifying kill sites using clusters of locations from GPS-collared wolves in Voyageurs National Park, Minnesota. We identified 22 sites where wolves from 4 different packs killed beavers. We classified these kill sites into 8 categories based on the beaver-habitat type near which each kill occurred. Seasonal variation existed in …

Problems Of Multi-Species Organisms: Endosymbionts To Holobionts, David C. Queller, Joan E. Strassmann

Biology Faculty Research

The organism is one of the fundamental concepts of biology and has been at the center of many discussions about biological individuality, yet what exactly it is can be confusing. The definition that we find generally useful is that an organism is a unit in which all the subunits have evolved to be highly cooperative, with very little conflict. We focus on how often organisms evolve from two or more formerly independent organisms. Two canonical transitions of this type—replicators clustered in cells and endosymbiotic organelles within host cells—demonstrate the reality of this kind of evolutionary transition and suggest conditions that …