Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 95 for “"species range"”.
-
The responses of Arabidopsis lyrata ssp. petraea to environmental stimuli
… varying environmental conditions throughout the species’ range. A. l. petraea is consequently an appropriate test system to study the effects of abiotic stress on species’ distributions and for investigation of local adaptation. The main objective of this study was to investigate whether or not …
-
The Effects of natural Gas Development on Density, Reproductive Success and Nest Survival of Grassland Songbirds in South-Western Saskatchewan
… birds are poorly understood but are often species-specific and vary across the species’ range. The purpose of my research is to (1) quantify aspects of grassland songbird breeding biology and (2) determine the effects of natural gas development on density and reproductive success of …
-
DDRAD-seq based identification of genetic markers to facilitate the assessment of clonal versus sexual reproduction in dichrostachys cinerea
… is a semideciduous nitrogen-fixing tree species belonging to the Fabaceae family and is native to parts of Africa, India and Northern Australia. In addition to propagation via seed dispersal, the species is capable of asexual reproduction via the process of root suckering. D. cinerea can …
-
Phylogeographic and environmental DNA analysis of the mudpuppy (necturus maculosus maculosus)
<p>Understanding species’ genetic diversity allows for informed management that preserves evolutionary potential. Informed management becomes crucial as genetic diversity declines and species become susceptible to threats such as climate change. For some species, it can be difficult to determine …
-
Disturbance-based restoration for recovery of pitch pine (Pinus rigida) in the Thousand Islands Ecosystem: a comparison of prescribed fire and mechanical disturbance on seedling regeneration
… associated with wildfire in the core of its range, however the association becomes less certain towards the species’ range margins. I tested the efficiency of a prescribed fire and mechanical disturbance treatment on increasing P. rigida seedlings using a Before-After Control-Impact (BACI) …
-
Biogeographical patterns of southern African marine invertebrates
… of patterns for a given area. The tendency for species richness and diversity to increases towards the equator, where both peak, is a much debated and tested pattern. Underlying mechanisms thought to cause this pattern are: gradients in temperature, stress, productivity, competition, predation, …
-
Demographic and Genetic Consequences of Small Population Size in Remnant Populations of Arabis georgiana Harper (Georgia Rockcress)
… structure in remnant populations across the species' range was performed. In addition to updating census information on remnant populations of A. georgiana, chapter one represents the first critical evaluation of traits associated with the phenological and reproductive success in this …
-
Applications of the IUCN Red List in evaluating global extinction risk of timber tree species.
… The world’s wild-growth timber tree species additionally face pressure from unsustainable and illegal harvest practices. Despite the threats to these economically valuable species, our understanding of their extinction risk remains incomplete and outdated. In fact, many timber tree …
-
Spatial Patterns and Multi-Scale Habitat Selection of the Mudsnake (Farancia Abacura) at the Northern Limits of Its Range
… selection are paramount to understanding a species' ecological needs and preferences. In this study I radiotracked 15 Mudsnakes (Farancia abacura) at Mingo National Wildlife Refuge in southeastern Missouri. Consistent with anecdotal information regarding the species, Mudsnakes were highly …
-
Phylogeography and Diversification of the Greenish Blue Butterfly (Plebejus Saepiolus) in Western North America
… create a disjunct and complex distribution in a species range. The Greenish Blue Butterfly, Plebejus saepiolus (Lycaenidae, Polyomattini), is a species which is widespread in North America, but populations are restricted to montane habitat. Here we use molecular genetic data and morphometric …
-
Phylogeography and Diversification of the Greenish Blue Butterfly (Plebejus Saepiolus) in Western North America
… create a disjunct and complex distribution in a species range. The Greenish Blue Butterfly, Plebejus saepiolus (Lycaenidae, Polyomattini), is a species which is widespread in North America, but populations are restricted to montane habitat. Here we use molecular genetic data and morphometric …
-
Habitat Use and Spatial Ecology of Blanding's Turtle, Emydoidea Blandingii, on Squaw Creek National Wildlife Refuge, Mound City, Missouri
Information on movements and home range size of endangered vertebrates is essential to conservation planning. I studied the habitat use and spatial ecology of Blanding's turtle Emydoidea blandingii at Squaw Creek National Wildlife Refuge in northwest Missouri at the southwestern limit of the …
-
Latitudinal Gradient Facilitates Adaptive Population Differentiation of Campanulastrum americanum (American Bellflower)
… in the most northern and southern extent of the species distribution: Hastings, MI and Columbus, GA. I observed adaptive population differentiation of northern and southern populations. Both reproductive and phenological traits of plants of southern origin were differentiated from plants of …
-
Maternal Effects and Offspring Behavior: Potential Contributors to the Lack of Recruitment in Mississippi Gopher Tortoises (<i>Gopherus polyphemus</i>)
… in Mississippi than in any other part of the species’ range , and most hatchlings die within the first year. There are few refuges where survival and hatching success is high. Here I compare two populations that differ in recruitment and offspring survival for differences in corticosterone. …
-
Population ecology of landlocked Arctic charr, <i>Salvelinus alpinus L</i>., in the Canadian High Arctic
… at 81 oN, close to the northerly extreme of the species range. They were single-species populations consisting of two distinct size modes, "Dwarf" and "Normal" charr, but with major differences both in size and relative numbers between the lakes. Tentative correlations between population …
-
Status and breeding ecology of the loggerhead shrike in Virginia
… substantially in Virginia and other parts of the species' range. Loggerhead shrikes should be considered for federal threatened status. I studied breeding chronology, productivity, and habitat use of 20 loggerhead shrike pairs in 1985 and 36 pairs in 1986. Yearly productivity in this Ridge and …
-
Evolution and Ecology of Flyingfishes (Teleostei:Exocoetidae)
… are a family of 53 epipelagic marine species distributed throughout tropical and subtropical surface waters. They form a key mid-trophic link between zooplankton and predators, and have evolved special adaptations to survive in the open ocean. However, little is known about their basic …
-
The eco-evolutionary consequences of multiple introductions for colonizing individuals
… biological control, climate change-induced species range shifts, and reintroductions of rare species. Propagule pressure, which comprises the number of introduction events (propagule number) and the number of individuals per introduction event (propagule size), consistently correlates with a …
-
Molecular evolutionary analysis of the American pika (Ochotona princeps)
… of 54 candidate genes for adaptation in two subspecies of <em>O. princeps</em> using draft genomes available from public databases. I constructed phylogenies using the two <em>O. princeps </em>alleles and homologs from other mammal species, and then used the CODEML module of PAML to detect …
-
Unlocking the genetic diversity of the undomesticated rice relative Oryza longistaminata
… Oryza longistaminata, which is native to a broad range of habitats throughout sub-Saharan Africa, is a valuable resource improving O. sativa with genes conferring biotic and abiotic stress tolerances, increased yield, super-ratooning ability, and floral traits conducive to hybrid rice production. …
Page 1 of 5