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Full-Text Articles in Life Sciences

Were Neandertal Humeri Adapted For Spear Thrusting Or Throwing? A Finite Element Study, Michael Anthony Berthaume Nov 2014

Were Neandertal Humeri Adapted For Spear Thrusting Or Throwing? A Finite Element Study, Michael Anthony Berthaume

Masters Theses

An ongoing debate concerning Neandertal ecology is whether or not they utilized long range weaponry. The anteroposteriorly expanded cross-section of Neandertal humeri have led some to argue they thrusted their weapons, while the rounder cross-section of Late Upper Paleolithic modern human humeri suggests they threw their weapons. We test the hypothesis that Neandertal humeri were built to resist strains engendered by thrusting rather than throwing using finite element models of one Neandertal, one Early Upper Paleolithic (EUP) human and three recent human humeri, representing a range of cross-sectional shapes and sizes. Electromyography and kinematic data and articulated skeletons were used …


Empirical Evaluation Of Proxies For The Acquisition Costs Of Protected Areas Suggests Care Is Needed To Deliver The Promise Of Cost-Effective Conservation, Nathan James Sutton Aug 2014

Empirical Evaluation Of Proxies For The Acquisition Costs Of Protected Areas Suggests Care Is Needed To Deliver The Promise Of Cost-Effective Conservation, Nathan James Sutton

Masters Theses

Given limited budgets, conservation organizations need to efficiently allocate their resources for biodiversity protection. While many organizations combine socioeconomic and biological data to identify areas with the highest biological return per dollar invested, it is less clear how uncertainty in socioeconomic data affects this planning process. In Chapter 1, we show how uncertainty due to proxy choice and spatial averaging affect conservation planning by comparing average agricultural land values, a common proxy for the acquisition costs of protected areas, to a case study recent protected area investments in the Eastern US. We find this proxy explains little variation and significantly …


Evaluating Pollination Ecology Of The Endangered Pityopsis Ruthii (Small) Small (Asteraceae), Philip Anthony Moore May 2014

Evaluating Pollination Ecology Of The Endangered Pityopsis Ruthii (Small) Small (Asteraceae), Philip Anthony Moore

Masters Theses

Pityopsis ruthii (Small) Small, also known as Ruth’s golden aster, is a federally endangered herbaceous perennial, endemic to two river systems, the Hiwassee and the Ocoee, within the Cherokee National Forest, Polk County, Tennessee. There are approximately 13,000 individuals that may be at high risk of short-term extirpation (Thompson and Schwartz, 2006). Little is known of the basic reproduction and life history of P. ruthii. Clebesh and Sloan (1993), Cruzan (2001), Park (1998), and Wadl et al. (2014) found evidence that seed production and seed viability are highly variable. Clebesh and Sloan (1993) indicated that pollinator visitation was highly temporal …


Aspects Of The Trophic Ecology Of An Invertivorous Snake Community, Meagan Amanda Thomas Jan 2014

Aspects Of The Trophic Ecology Of An Invertivorous Snake Community, Meagan Amanda Thomas

Masters Theses

Understanding the significance of trophic links has been of interest to ecologists for decades, likely because food web studies have the potential to reveal a considerable amount of information in the fields of ecosystem and community ecology. Despite the intrinsic benefits that come from elucidating food web structures, doing so is often problematic because of the complex and dynamic nature of ecological communities. The dietary ecology of small-bodied invertivorous snakes remains relatively understudied compared to other snake species. Many of these species are abundant throughout their range, making them ideal organisms for studying community-level questions. I employed a combination of …


Pelagic Larval Duration Links Life History Traits And Species Persistence In Darters (Percidae: Etheostomatinae), Morgan Jessica Douglas Aug 2013

Pelagic Larval Duration Links Life History Traits And Species Persistence In Darters (Percidae: Etheostomatinae), Morgan Jessica Douglas

Masters Theses

Pelagic larval duration (PLD) likely influences evolutionary processes including dispersal, genetic connectivity, and extinction in aquatic organisms. PLD has been well studied in marine systems, but very few freshwater species have been studied. Darters are a diverse group of freshwater North American fish with available information on the length of this stage from propagation efforts. There is surprising variation in the length of this stage ranging from 0 to 60 days. By compiling information from Conservations Fisheries, Inc. (Knoxville, TN) and the literature, we were able to make comparisons between the PLD of 23 species and other life history characteristics. …


Genetic Variation And Dispersal In Penstemon Hirsutus And P. Tenuiflorus, Anna Katherine Becker May 2013

Genetic Variation And Dispersal In Penstemon Hirsutus And P. Tenuiflorus, Anna Katherine Becker

Masters Theses

Studying plant-pollinator relationships essential for understanding angiosperm evolution. In the large endemic genus Penstemon (Plantaginaceae), shifts in pollination syndrome are proposed to be important for explaining taxonomic and morphological diversity (Wilson et al., 2004; Wolfe et al., 2006). However, little work has been done to determine the relationship between morphological and genetic divergence within pollination syndromes. This study utilized genetic data to explore whether divergence in corolla morphology among nine closely related, bee pollinated Penstemon species was consistent with pollinator-driven selection.

Bee pollinated species in Penstemon subsection Penstemon are often divided into two morphological groups based on inflation of the …


Mating System Biology Of The Florida Native Plant: Illicium Parviflorum, Nicholas Earl Buckley Aug 2012

Mating System Biology Of The Florida Native Plant: Illicium Parviflorum, Nicholas Earl Buckley

Masters Theses

Self-incompatibility is thought to have played a profound role in the evolution of the angiosperms. However, there is little evidence of self-incompatibility systems in early diverging lineages of flowering plants. Illicium parviflorum, one such early-divergent angiosperm, is an evergreen perennial species endemic to central Florida, particularly within the Ocala National Forest. Although locally abundant, I. parviflorum is currently listed as endangered at the state level due to being under constant threat of habitat disturbance and over-harvesting. Notably, this species had been described as self-incompatible due to its low seed-set. However, low seed set may also be a result of …


Identifying The Spatial Distribution Of Three Plethodontid Salamanders In Great Smoky Mountains National Park Using Two Habitat Modeling Methods, Matthew Stephen Kookogey May 2012

Identifying The Spatial Distribution Of Three Plethodontid Salamanders In Great Smoky Mountains National Park Using Two Habitat Modeling Methods, Matthew Stephen Kookogey

Masters Theses

The main objective was to create habitat models of three plethodontid salamander species (Desmognathus conanti, D. ocoee, and Plethodon jordani) in GSMNP. To investigate the relationships between salamanders and their habitats, I used three models—logistic regression with use-availability sampling, logistic regression with case-control sampling, and Mahalanobis distance (D2)—for each species to gain a robust view of the relationships. The secondary objective was to compare the different modeling methods within and across the three species. Elevation was the dominant variable for all three species.

D2 for D. conanti predicted low elevations, close proximity …


An Investigation Of Stratigraphic Evidence For An Abrupt Climatic Event 8200 Yr Bp In Valle De Las Morrenas, Costa Rica, Brian Thomas Watson May 2011

An Investigation Of Stratigraphic Evidence For An Abrupt Climatic Event 8200 Yr Bp In Valle De Las Morrenas, Costa Rica, Brian Thomas Watson

Masters Theses

Lago de las Morrenas 4 (9.498056° [degrees] N, 83.486111° [degrees] W, 3466 m elev.) is the lowest lake in a chain of glacial lakes located in the Valle de las Morrenas, a valley facing almost due north from Cerro Chirripó, the highest peak in the Cordillera de Talamanca in Costa Rica. Coarse resolution analyses of pollen, microscopic charcoal, and loss-on-ignition of a ca. 10,000 year sediment record from Lago de las Morrenas 4 was carried out to complement and extend previous research on the environmental history of the Chirripó highlands and to provide context for high-resolution sampling and analysis of …


Using Stable Isotopes To Assess Longitudinal Diet Patterns Of Black Bears (Ursus Americanus) In Great Smoky Mountains National Park, Jennapher Lynn Teunissen Van Manen May 2011

Using Stable Isotopes To Assess Longitudinal Diet Patterns Of Black Bears (Ursus Americanus) In Great Smoky Mountains National Park, Jennapher Lynn Teunissen Van Manen

Masters Theses

Long-term diet patterns based on stable isotope analysis may be helpful to understand changes in food selection of black bears (Ursus americanus) over time and guide management programs to reduce human-bear conflicts. An enriched stable carbon isotope signature indicates an anthropogenic food source in the diet and an enriched nitrogen signature indicates a higher tropic level for a species. I examined longitudinal feeding patterns from 117 hair samples of black bears live captured in Great Smoky Mountains National Park during 1980–2001 using stable carbon and nitrogen isotope analysis from hair samples. I developed a set of a priori …


Evaluating Ecological Restoration In Tennessee Hardwood Bottomland Forests, Elizabeth Anne Summers Aug 2010

Evaluating Ecological Restoration In Tennessee Hardwood Bottomland Forests, Elizabeth Anne Summers

Masters Theses

Hardwood bottomland ecosystems provide critical habitat for various wildlife among numerous ecosystem services. Since the 1800s, these forested wetlands have been logged and drained for agriculture. The federal government passed a series of legislative acts that protected wetlands and provided monetary support for restoration. The Wetlands Reserve Program (WRP) was established in 1990 with the goal of restoring ecological function in wetlands. Although several studies have measured plant and wildlife responses to WRP restorations, no standard protocol has been developed to monitor the state of ecological restoration at sites. Index of biotic integrity (IBI) models are commonly used to evaluate …


Seasonality, Variation In Species Prevalence, And Localized Disease For Ranavirus In Cades Cove (Great Smoky Mountains National Park) Amphibians, Megan Todd-Thompson May 2010

Seasonality, Variation In Species Prevalence, And Localized Disease For Ranavirus In Cades Cove (Great Smoky Mountains National Park) Amphibians, Megan Todd-Thompson

Masters Theses

World-wide amphibian declines sparked concern and encouraged investigation into potential causes beginning in the 1980’s. Infectious disease has been identified as one of the major potential contributors to amphibian declines. For example, Ranavirus has caused amphibian die-offs throughout the United States. Investigators isolated Ranavirus from dead or moribund amphibians during large-scale die-offs of amphibians in the Cades Cove area of Great Smoky Mountains National Park in 1999-2001. In 2009, after nearly a decade without follow-up monitoring, I undertook an investigation to determine if the virus persisted in the area, and if so, to assess spatial, temporal, and taxonomic patterns in …