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Using Geographically Structured Evaluations To Assess Performance And Transferability Of Ecological Niche Models For Species With Many Occurrence Records; A Test Using The Caribbean Spiny Pocket Mouse, Heteromys Anomauls, Aleksandar Radosavljevic

Dissertations and Theses

No abstract provided.

Biological Reserves Under Climate Change; A Case Study In Brazil's Atlantic Rainforest, Maria Amin

Dissertations and Theses

No abstract provided.

Healthy Choices; Preferential Foraging Of Insects Within Senescent, But Nutrient-Rich, Tropical Flowers., Amie Whigman

Dissertations and Theses

No abstract provided.

Anatomical Identification Of Primary Auditory Cortex In The Developing Gerbil, Luis Pendola

Dissertations and Theses

Cortical development is an active field of study. The gerbil provides an excellent model for research because at the moment of birth its brain is rather immature, anatomically and functionally. Furthermore, the gerbil auditory cortex is particularly amenable to investigation in that the gerbil's onset of hearing occurs approximately after 14 days of postnatal life. Despite these advantages of the gerbil for auditory cortex development not much is known about the anatomy of the postnatal gerbil auditory cortex. For example, where is the gerbil auditory cortex? Prior to the onset of hearing, sounds cannot be used to localize auditory cortex. …

The Development Of Hearing In Rats; Reliability Of Wave 1 As A Determinant Of Auditory Maturation And Contributions Of Peripheral Structure Progression, Aminat Saliu

Dissertations and Theses

No abstract provided.

Population Structure Of Island-Associated Pantropical Spotted Dolphins (Stenella Attenuata) In Hawaiian Waters, Sarah Shelby Courbis

Dissertations and Theses

Understanding gene flow, diversity, and dispersal patterns is important for predicting effects of natural events and anthropogenic activities on dolphin populations. With the very recent exceptions of false killer whales (Pseudorca crassidens), spinner dolphins (Stenella longirostris), and common bottlenose dolphins (Tursiops truncatus), Hawaiian odontocete species are managed as single stocks within the U.S. Hawaiian Exclusive Economic Zone. These exceptions are a result of recent studies that have indicated that some species have populations that show fidelity to individual islands or groups of islands, resulting in genetic differentiation, often with management implications. The first part …

Total Mercury In Stranded Marine Mammals From The Oregon And Southern Washington Coasts, Nathan J. Wintle

Dissertations and Theses

Muscle samples from 105 marine mammals stranded along the Oregon-Washington coasts (2002-2009) were tested for levels of total mercury by Cold Vapor Atomic Fluorescence Spectrometry. The total mercury present is predominantly in the form of highly toxic methylmercury. After normalizing muscle tissue to 75% water weight, due to variance in water content, Steller sea lions (Eumetopias jubatus) and northern elephant seals (Mirounga angustirostris) exhibited the highest mean concentrations of total mercury followed by harbor seals (Phoca vitulina), harbor porpoises (Phocoena phocoena), and California sea lions (Zalophus californianus); 0.34 ± 0.278, …

Molecular Genetic Analysis Of Creld1 In Patients With Heterotaxy Disorder, Samaneh Zhian

Dissertations and Theses

Heterotaxy refers to the abnormal arrangement of internal organs in relation to each other. Model organism studies have shown that functions of more than eighty genes are required for normal asymmetric left-right organ development. CRELD1 has been shown to be necessary for proper heart development and mutations in CRELD1 are known to increase risk of cardiac atrioventricular septal defects (AVSD). AVSD is the most common form of heart defect associated with heterotaxy, and we have previously shown that some individuals heterotaxy-related AVSD have mutations in CRELD1.

Therefore, we propose to examine the CRELD1 gene in a large sample of …

Using Archaeological Fish Remains To Determine The Native Status Of Anadromous Salmonids In The Upper Klamath Basin (Oregon, Usa) Through Mtdna And Geochemical Analysis, Alexander E. Stevenson

Dissertations and Theses

Within the Upper Klamath Basin, Oregon, the native status of anadromous salmonids (Oncorhynchus spp.) has been a long standing question. Ongoing efforts to establish if these fish were native to the region prior to the construction of the Copco I Dam on the Klamath River (c.1917) have relied on sparse, contradictory and sometimes unreliable historic documentation and informant testimony. Current restoration projects with very high financial and social costs necessitate accurate and reliable data on salmonid species which once called the region home. Often, archaeolofaunal remains present a novel way to determine species present in an area prior to …

Postfledging Survival And Habitat Use Of Spotted Towhees (Pipilo Maculatus) In An Urban Park, Amy Ann Shipley

Dissertations and Theses

Habitat fragmentation, and the resulting increase in edge habitat, has important effects on birds, including the increased probability of nest predation, changes in habitat structure, and the increased presence of non-native plant species. It is critical to understand the effects of fragmentation at all stages of the avian life cycle, including the often overlooked postfledging period. Because much of juvenile mortality occurs during the immediate postfledging period, and juvenile mortality contributes substantially to population dynamics, it is necessary to understand if fledgling survival is reduced in edge habitats and if fledglings' survival is influenced by their habitat use. During 2008 …

Propagule Pressure And Disturbance Drive The Spread Of An Invasive Grass, Brachypodium Sylvaticum, Laura Alayna Vician Taylor

Dissertations and Theses

The invasibility, or susceptibility of an ecosystem to biological invasion is influenced by changes in biotic and abiotic resistance often due to shifts in disturbance regime. The magnitude of invasive propagule pressure interacts with an ecosystem's invasibility to determine the extent of a biological invasion. I examined how propagule pressure, forest community structure and disturbance interact to influence the invasibility of temperate Pacific Northwest forests by the newly-invasive grass, Brachypodium sylvaticum. My goal was to identify which of these factors is most instrumental in enabling the shift from establishment to population growth in B. sylvaticum at the edge of …

Interception In Open-Grown Douglas-Fir (Pseudotsuga Menziesii) Urban Canopy, Mitchell Bixby

Dissertations and Theses

I hypothesized that Douglas-fir trees (Pseudotsuga menziesii) standing apart from other trees ('open-grown') will intercept more rainfall than Douglas-fir trees standing near other trees ('closed-canopy'). Open-grown trees differ structurally and are more common in urban settings, yet have been infrequently studied. Existing literature, based primarily on closed-canopy trees, suggests Douglas-fir trees in Pacific Northwest forests intercept approximately 25% of rainfall annually. Because open-grown trees have more vertical leaf area than individual trees in closed-canopy forests, I expected to find higher interception by open-grown trees.

I collected throughfall under four open-grown Douglas-firs using six static collectors ('buckets') per tree, …