Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Abundance (1)
- Acid (1)
- Addiction (1)
- Adolescent (1)
- Agaricales (1)
-
- Alces alces (1)
- Alcohol (1)
- Ants (1)
- Bats (1)
- Behavior (1)
- Biodiversity (1)
- Biogeography (1)
- Biological control (1)
- Browsing (1)
- Cahaba Pond (1)
- Cantharellales (1)
- Central Appalachia (1)
- Charcoal (1)
- Clavariaceae (1)
- Community ecology (1)
- Delay Discounting (1)
- Depletion method (1)
- Disease (1)
- Distribution (1)
- Echolocation (1)
- Fire (1)
- Forest disturbance (1)
- Fungal systematics (1)
- Fungal taxonomy (1)
- Habitat fragmentation (1)
Articles 1 - 10 of 10
Full-Text Articles in Life Sciences
Systematics And Diversification Patterns Of Morphologically And Ecologically Diverse Lineages Of Agaricomycetes: Clavariaceae And Cantharellales, Joshua Mark Birkebak
Systematics And Diversification Patterns Of Morphologically And Ecologically Diverse Lineages Of Agaricomycetes: Clavariaceae And Cantharellales, Joshua Mark Birkebak
Doctoral Dissertations
The recent advent of molecular tools and methods to understand the diversity of living organisms allows for exploration of former untestable theories concerning the diversity of fungi. Here we assess the morphologically based classification of the family Clavariaceae in light of molecular phylogenetic reconstruction and propose a revised classification base on natural assemblages. We used stable isotope ratios to uncover a biotrophic nutritional mode for much of the family, which had not been well understood historically. We also investigate several enigmatic lineages of agaricoid or cantharelloid fruiting body producing fungi within a clade of otherwise clavarioid fruiting bodies. We provide …
Linking Physiology And Biogeography: Disentangling The Constraints On The Distributions Of Ant Species, Lacy Danikas Chick
Linking Physiology And Biogeography: Disentangling The Constraints On The Distributions Of Ant Species, Lacy Danikas Chick
Doctoral Dissertations
Understanding the factors that limit the distribution of species is at the core of ecological and biogeographical research, and is critical if we are to predict the responses of key ecosystem components to ongoing climatic changes. My doctoral research seeks to provide an understanding of how thermal physiology influences species’ distributions and better define the mechanisms underlying geographic variation in biodiversity. By using natural temperature gradients (both elevational and latitudinal) and coupling controlled laboratory experiments with field observations and null modeling approaches, I was able to document the role of inter-specific variation in thermal physiology and, more interesting, inter-population variation …
Complex Effects Of Ungulate Browsers On Tree Recruitment And Herbaceous Layers In New England Temperate Forests, Edward K. Faison
Complex Effects Of Ungulate Browsers On Tree Recruitment And Herbaceous Layers In New England Temperate Forests, Edward K. Faison
Doctoral Dissertations
Browsing by ungulates is a leading biotic disturbance in northern forest ecosystems and an important determinant of habitat, biodiversity, and ecosystem services. A large body of work has revealed that white-tailed deer (Odocoileus virginianus) at high densities alter forest understories in strong and predictable ways; however, less is known about how lower densities of deer and the combined effects of multiple herbivores influence forest understory vegetation, particularly in stands following canopy disturbance. Using fenced exclosures, remote cameras and other field observations, I explored the foraging response and browsing effects of low densities of deer and moose (Alces …
Behavioral And Neural Mechanisms Of Impulsive Choice, Jesse Mcclure
Behavioral And Neural Mechanisms Of Impulsive Choice, Jesse Mcclure
Doctoral Dissertations
Impulsive choice is defined as the preference for a small immediate reward over a larger delayed reward. Individual variablity in impulsive choice correlates with many socially relevant behaviors. Although forms of impulsive choice have been studied in both behavioral ecology and psychology, the exchange of knowledge between these fields is just beginning. Drawing from both of these fields will improve our research methods allowing for a more detailed understanding of this complex behavior. Existing tasks to measure impulsive choice conflate the delay and quantity of the reward. To address this, I have drawn from foraging research to establish a method …
The Effectiveness And Applicability Of Amphibians As Indicator Species For Long-Term Monitoring Of Ecological Changes In New England Forests, Ahmed Siddig
Doctoral Dissertations
The objective of this study is to assess the potential of two amphibians species, Eastern Red-backed Salamander (Plethodon cinereus (Green)) and Eastern Red-spotted Newt (Notopthalmus viridescens viridescens Rafinesque), as indicator species of forest disturbances at Harvard Forest, located in Petersham, Massachusetts, United States. Specifically, I 1) assess the impacts of these focal species to decline of hemlock forests in Harvard Forest; 2) calibrate abundance indices of P. cinereus based on artificial and natural objects surveys with a population size estimator based on depletion sampling; and 3) assess the potential of these salamanders as indicator species by developing an …
Conservation Planning In A Changing World, Austin Walker Milt
Conservation Planning In A Changing World, Austin Walker Milt
Doctoral Dissertations
As a science and practice dedicated to preventing, stopping, and reversing negative effects on nature, conservation is constantly faced with new challenges. Combine this fact with the rise of large, freely available datasets and computational power, and the result is a need to advance the methods and conceptual approach to conservation planning. In my dissertation I present novel methods and address research questions that aim to keep conservation science and practice relevant and effective in a changing world. This picture of continual change is illustrated in Chapter 1, in which I explore how the ongoing collection of observations of rare …
Evidence Of Late Quaternary Fires From Charcoal And Siliceous Aggregates In Lake Sediments In The Eastern U.S.A., Joanne P. Ballard
Evidence Of Late Quaternary Fires From Charcoal And Siliceous Aggregates In Lake Sediments In The Eastern U.S.A., Joanne P. Ballard
Doctoral Dissertations
The late-glacial transition to the Holocene, 15,000–11,600 cal yr BP, is an enigmatic period of dynamic global changes and a major extinction event in North America. Fire is an agent of disturbance that transforms the environment physically and chemically, and affects plant community composition. To improve understanding of the linkages between fire, vegetation, and climate over the late glacial and Holocene in the eastern U.S., I analyzed lake-sediment cores for charcoal and indicators of wood ash, and compared results to existing pollen records. A new microscopic charcoal record from Anderson Pond, Tennessee revealed high fire activity from 23,000–15,000 cal yr …
Evolution And Phylogeny Of The Parasitoid Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke
Evolution And Phylogeny Of The Parasitoid Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke
Doctoral Dissertations
The first molecular phylogenetic analysis of the agriculturally important parasitoid subfamily Phasiinae (Diptera: Tachinidae) is presented, estimated from 128 worldwide taxa (80 genera) and approximately 7.6 kilobases of nuclear data. Special emphasis is placed on taxa with controversial taxonomic placement. The resultant phylogenetic tree is used to reconstruct ancestral character states, trace the evolution of significant adaptive traits within the Tachinidae, and test hypotheses about the classification of Phasiinae. Subfamily placements of the taxa Eutherini, Epigrimyiini, Litophasia, Strongygastrini, and Parerigonini are confidently resolved, the former three within Dexiinae and the latter two within Phasiinae. Due to sparse molecular evidence, …
Bats And Disease: Behavioral And Community Responses Of Southern Bat Populations During The White-Nose Syndrome Epizootic, Riley Fehr Bernard
Bats And Disease: Behavioral And Community Responses Of Southern Bat Populations During The White-Nose Syndrome Epizootic, Riley Fehr Bernard
Doctoral Dissertations
This dissertation investigates regional differences in the behavior and activity of bats in eastern North America during the white-nose syndrome epizootic, specifically in the understudied region of the Southeastern United States. An introductory section provides a brief review of the history of white-nose syndrome, an emerging infectious disease in bats, and its introduction into North America. Chapter one provides the first documented evidence of bat activity outside of hibernacula throughout winter. The research presented in chapter two attempts to explain the variation in load and prevalence of P. destructans among species, sites and between years. Finally, chapter three examines the …
The Effect Of Thermoregulation And Roads On The Movements And Habitat Selection Of Moose In Massachusetts, David W. Wattles
The Effect Of Thermoregulation And Roads On The Movements And Habitat Selection Of Moose In Massachusetts, David W. Wattles
Doctoral Dissertations
Massachusetts, U.S.A. is located along the southern boundary of the geographic range of moose (Alces alces) in North America. This is an atypical environment for moose, because of its extremely high levels of human development and high year-round temperatures, which are possibly at the limits of moose physiological tolerances. I investigated the role of these two factors on moose movements and habitat selection to determine how human development of the landscape and temperature influence moose occupation of this extreme environment. In addition, the response of moose to these factors provides insights into the influence of development and temperature …