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Full-Text Articles in Life Sciences

Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman Dec 2022

Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman

Electronic Theses and Dissertations

The southern Appalachian Mountains have among the highest salamander diversity in the world, largely due to local speciation in the family Plethodontidae. Plethodontid salamanders (i.e., lungless salamanders) are particularly sensitive to habitat climate conditions due to their reliance on cutaneous respiration, and their immediate environmental conditions (microhabitat) likely influence their dispersion and activity more than the large-scale atmospheric conditions. The Northern Gray-cheeked salamander (Plethodon montanus) is restricted to high elevations in the Appalachian Mountains. Our goal was to investigate the relationship between P. montanus and its microhabitat by examining behavioral preference for climatic conditions, characterizing the microclimate with …


The Paleoecology Of High-Elevation Bison In The Greater Yellowstone Ecosystem And Implications For Modern Bison Conservation, Darian Bouvier Aug 2022

The Paleoecology Of High-Elevation Bison In The Greater Yellowstone Ecosystem And Implications For Modern Bison Conservation, Darian Bouvier

Electronic Theses and Dissertations

The national mammal of the United States, the American Bison (Bison bison) was once nearly extinct. Populations have recovered to the degree that thousands roam the Great Plains today. Due to their large numbers and body size, this species has an oversized impact on the ecological communities where it lives and is considered a keystone herbivore in modern North American grasslands. This study explores the detailed, seasonally resolved, paleoecology of seven bison from the Greater Yellowstone Ecosystem during the Late Holocene through stable isotope analyses and species niche modeling. Isotopic analyses of δ13C, δ15N, …


Not All Pollinator Gardens Are Created Equally: Determining Factors Pertinent To Improving Pollinator Garden Effectiveness, Travis Watson May 2021

Not All Pollinator Gardens Are Created Equally: Determining Factors Pertinent To Improving Pollinator Garden Effectiveness, Travis Watson

Electronic Theses and Dissertations

Increasing evidence documenting the decline of insect populations, resulting from increasing human disturbances has resulted in efforts to establish pollinator gardens to provide additional resources for insect populations. However, our understanding of biotic and abiotic garden characteristics important for attracting and sustaining pollinator diversity is limited. Here, we evaluated 17 pollinator gardens to evaluate the effect of five biotic and three abiotic garden characteristics on pollinator species richness, abundance, and proportional representation of four pollinator functional groups. Plant species richness positively influenced pollinator richness and negatively influenced flower visitation. Bombus proportional abundance responded to several variables (distance to vegetation, plant …


Congruence And Temporal Variation Of Floral Visitation And Pollen Transport Networks In Southern Appalachia, Daniel A. Barker Aug 2020

Congruence And Temporal Variation Of Floral Visitation And Pollen Transport Networks In Southern Appalachia, Daniel A. Barker

Electronic Theses and Dissertations

Observation of floral visitation is an accepted method to describe plant-pollinator interactions despite potential biases. Collecting pollen from pollinators offers new insights on the structure and function of plant-pollinator communities. Furthermore, the strength and frequency of plant-pollinator interactions can vary across temporal scales. However, within-season and within-day (morning vs. evening) variation in plant-pollinator networks has been little studied. By evaluating variation in network structure across these biologically relevant time scales, we will gain a better understanding of the factors that shape plant-pollinator communities. The objectives of this study are to 1) Compare the structure of plant-pollinator networks built on floral …


Chronoecology Of A Cave-Dwelling Orb-Weaver Spider, Meta Ovalis (Araneae: Tetragnathidae), Rebecca Steele May 2020

Chronoecology Of A Cave-Dwelling Orb-Weaver Spider, Meta Ovalis (Araneae: Tetragnathidae), Rebecca Steele

Electronic Theses and Dissertations

Circadian clocks enable coordination of essential biological and metabolic processes in relation to the 24-hour light cycle. However, there are many habitats that are not subject to this light cycle, such as the deep sea, arctic regions, and cave systems. This study analyzes the circadian pattern of isolated populations of a subterranean spider, Meta ovalis from two Tennessee caves and five Indiana caves. Locomotor activity was recorded with TriKinetics LAM50 Locomotor Activity Monitor under a 12-hour light (L), 12-hour dark (D) (LD 12:12) cycle preceding total darkness (DD). Significant differences were found within and among populations found in Tennessee cave …


Temporal Factors Affecting Foraging Patterns Of A Diurnal Orb-Weaving Spider, Micrathena Gracilis (Araneae: Araneidae), Mitchell Davis Long May 2020

Temporal Factors Affecting Foraging Patterns Of A Diurnal Orb-Weaving Spider, Micrathena Gracilis (Araneae: Araneidae), Mitchell Davis Long

Undergraduate Honors Theses

Several studies have investigated the ecological factors that affect behavior in Micrathena gracilis, a diurnal orb-weaving spider that forages on flying insects during the day. However, none yet have considered how the temporal distributions of prey and predator occurrences shape their daily behavioral rhythms, especially web construction, which involves a heavy energetic investment well in advance of potential nutritional benefit. Recently, several orb-weaving spider species have been shown to exhibit a variety of abnormal rhythms, suggesting that circadian clock-controlled rhythms may play an unexpected role in behavioral evolution. Despite the appearance of significant insect abundance in the evenings, M. gracilis …


Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner May 2019

Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner

Electronic Theses and Dissertations

North American black bears and brown bears can be difficult to distinguish in the fossil record due to similar dental and skeletal morphologies. Challenges identifying ursid material from Oregon Caves National Monument (ORCA) called for an accurate tool to distinguish the species. This study utilized a large database of lower tooth lengths and ratios in an attempt to differentiate black and brown bears in North America. Further, this project examined how these linear measurements differ geographically. Analysis of variance (ANOVA) found significant differences between black and brown bears from across North America for every variable studied. Stepwise discriminant analyses (DA) …


Escaping The Arrhenius Tyranny: Metabolic Compensation During Exposure To High Temperature In Daphnia, Bret L. Coggins May 2018

Escaping The Arrhenius Tyranny: Metabolic Compensation During Exposure To High Temperature In Daphnia, Bret L. Coggins

Electronic Theses and Dissertations

Poikilothermic organisms experience trade-offs by differential physiological demands generated by temperature extremes. Many such organisms exhibit acclimatory effects, adjusting their metabolism and physiology to recently experienced temperatures. One such acclimatory effect is metabolic compensation, the deceleration of biological rates below Arrhenius expectations. Daphnia magna is eurythermal, and if acclimated to mildly stressful temperatures first, survives longer in lethal temperatures. This study examined the effect of ambient temperature (5°C-37°C) and acclimation history (lifetime at 10°C or 25°C) on the oxygen consumption rates of 8 genotypes of Daphnia with high or low acute temperature tolerance. There were decelerations of respiratory rates across …


Niche Modeling For The Giant Panda, Ailuropoda Melanoleuca, And The Original Panda, Ailurus Fulgens: Habitat Preferences And Evolutionary Consequences, Lauren M. Lyon May 2017

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 …


Exploring The Relationship Between Behaviour And Neurochemistry In The Polyphenic Spider, Anelosimus Studiosus (Araneae: Theridiidae), Jennifer B. Price Aug 2016

Exploring The Relationship Between Behaviour And Neurochemistry In The Polyphenic Spider, Anelosimus Studiosus (Araneae: Theridiidae), Jennifer B. Price

Electronic Theses and Dissertations

The importance of social behaviour is evident in human society, but there are both costs and benefits associated with cooperation and sociality throughout the animal kingdom. At what point do the benefits outweigh the costs, and when do selective pressures favour sociality and colonization over solitude and independence? To investigate these questions, we have focused on an anomalous species of spider, Anelosimus studiosus, also known now as the northern social spider. Throughout its broad range, A. studiosus is solitary and aggressive, but recently, colonies of cooperative and social individuals have been observed at northern latitudes. This leads to two …


Demography And Disease Of The Rare Shrub Buckleya Distichophylla (Santalaceae) In Northeastern Tennessee, William Seth Ratliff Dec 2015

Demography And Disease Of The Rare Shrub Buckleya Distichophylla (Santalaceae) In Northeastern Tennessee, William Seth Ratliff

Undergraduate Honors Theses

Piratebush (Buckleya distichophylla (Nutt.) Torr.) is a rare, hemiparasitic shrub with the only extant populations in western North Carolina, northeastern Tennessee, and southwestern Virginia. The preferred natural hosts of piratebush, Carolina and eastern hemlocks, have seen sharp declines over the last decade due to the invasive hemlock woolly adelgid. Virginia pine, another important host of piratebush, is also susceptible to disease, specifically Cronartium appalachianum, a rust fungus for which piratebush is the secondary host. This study described and analyzed current demographic parameters of three Tennessee piratebush populations. Additionally, spatial patterns of disease and demographic characters were analyzed. These …


Diel Patterns Of Foraging Aggression And Antipredator Behavior In The Trashline Orb-Weaving Spider, Cyclosa Turbinata, James C. Watts May 2014

Diel Patterns Of Foraging Aggression And Antipredator Behavior In The Trashline Orb-Weaving Spider, Cyclosa Turbinata, James C. Watts

Electronic Theses and Dissertations

Few studies have rigorously assessed the adaptive value of diel rhythms in animals. We laid the groundwork for assessing the adaptive rhythm hypothesis by assaying diel rhythms of foraging and antipredator behavior in the orb-weaving spider Cyclosa turbinata. When confronted with a predator stimulus in experimental arenas, C. turbinata exhibited thanatosis behavior more frequently and for longer durations during the day. However, assays of antipredator response within webs revealed more complex diel patterns of avoidance behaviors and no pattern of avoidance behavior duration. Assays of prey capture behavior found that the likelihood of exhibiting prey capture behavior varied significantly …