Ecology and Evolutionary Biology Commons^™

What Drives Species Richness In Colorado's Alpine Tundra, Michael Kintgen

Regis University Student Publications (comprehensive collection)

Despite years of research, drivers of vascular plant species richness in Colorado’s alpine tundra habitats are largely unknown. Factors such as slope aspect, Pleistocene glaciation, nutrient levels, latitude and longitude, snow depth, and disturbance have been studied. Despite this research, few patterns have emerged. Research in Colorado has been conducted on a few well studied mountains. Aridity is one factor that has not been well studied but shows promise in explaining species richness. In Patagonia and the Swiss Alps, increasing aridity correlates with higher species richness. Here, a full species assessment was conducted on nine mountains previously under researched or …

Social Contact Patterns Can Buffer Costs Of Forgetting In The Evolution Of Cooperation, Jeffrey R. Stevens, Jan K. Woike, Lael J. Schooler, Stefan Lindner, Thorsten Pachur

Jeffrey Stevens Publications

Analyses of the evolution of cooperation often rely on two simplifying assumptions: (i) individuals interact equally frequently with all social network members and (ii) they accurately remember each partner's past cooperation or defection. Here, we examine how more realistic, skewed patterns of contact—in which individuals interact primarily with only a subset of their network's members—influence cooperation. In addition, we test whether skewed contact patterns can counteract the decrease in cooperation caused by memory errors (i.e. forgetting). Finally, we compare two types of memory error that vary in whether forgotten interactions are replaced with random actions or with actions from previous …

Mesotocin Influences Pinyon Jay Prosociality, Juan Duque, Whitney Leichner, Holly Ahmann, Jeffrey R. Stevens

Jeffrey Stevens Publications

Many species exhibit prosocial behavior, in which one individual’s actions benefit another individual, often without an immediate benefit to itself. The neuropeptide oxytocin is an important hormonal mechanism influencing prosociality in mammals, but it is unclear whether the avian homologue mesotocin plays a similar functional role in birds. Here, we experimentally tested prosociality in pinyon jays (Gymnorhinus cyanocephalus), a highly social corvid species that spontaneously shares food with others. First, we measured prosocial preferences in a prosocial choice task with two different payoff distributions: Prosocial trials delivered food to both the subject and either an empty cage or a partner …

Infection Dynamics Of Herpesvirus In Gopher Tortoises, Joanne Saldanha

Honors Undergraduate Theses

Gopherus polyphemus, commonly known as the Gopher Tortoise, is a dryland reptile native to the southeastern United States. It is commonly a resident of longleaf pine and dry oak sand hill habitats. It is considered a keystone species because they dig deep burrows that provide shelter to them as well as many other animals. Habitat loss, fragmentation, and disease are major threats and have caused this species to be federally listed as a threatened species under the Endangered Species Act (ESA). Disease is a major threat to the gopher tortoise’s survival, and with declining populations, the need to investigate …

Zero Textbook Cost Syllabus For Env 3009/Bio 4009 (Conservation Biology And Sustainable Development), Natalia Borrego

Open Educational Resources

Conservation biology is an interdisciplinary topic that explores how we can protect and maintain natural areas. Due to the resources we take and impacts we have on natural environments, this field is directly related to restoration ecology (restoring natural areas) and sustainable development/natural resource management. We will explore the basis for these related fields from an ecological, social, legal, and cultural perspective, as all conservation and management projects take place in the larger human landscape. We will consider how we measure biodiversity, why it matters, why is it is threatened, and how we can manage (protect, restore, maintain, use) it …

Eleven Strategies For Getting Into Graduate School In Ecology & Evolutionary Biology, Eric Walters

Biological Sciences Faculty Publications

Getting into graduate school can be tough if you have not done your homework. I outline eleven strategies for increasing your chances of successfully being accepted into an ecology or evolutionary biology lab. Try to get good grades as an undergraduate, do well on the Graduate Record Exam (if applicable), join a lab reading group or undertake an undergraduate thesis, take time to forge relationships so you can have strong reference writers, obtain relevant work experience, author a publication, read peer-reviewed literature, attend national meetings, come up with some good research ideas, develop a relationship with a potential advisor, and …

Muskrats, James E. Miller

Wildlife Damage Management Technical Series

The muskrat (Ondatra zibethicus) is a common, semi-aquatic rodent native to the United States (Figure 1). It spends its life in aquatic habitats and is well adapted for swimming.

Although muskrats are an important part of native ecosystems, their burrowing and foraging activities can damage agricultural crops, native marshes and water control systems, such as aquaculture and farm ponds and levees. Such damage can significantly impact agricultural crops like rice that rely on consistent water levels for growth.

Muskrats also cause damage by eating agricultural crops, other vegetation, and crayfish, mussels and other aquaculture products. Loss of vegetation …

Wild Turkeys, James E. Miller

Wildlife Damage Management Technical Series

Like other bird and mammal species whose populations have been restored through conservation efforts, wild turkeys (Figure 1) are treasured by many recreationists and outdoor enthusiasts. Wild turkeys have responded positively to wildlife habitat and population management. In some areas, however, their increased populations have led to increased damage to property and agricultural crops, and threats to human health and safety. Turkeys frequent agricultural fields, pastures, vineyards and orchards, as well as some urban and suburban neighborhoods. Because of this, they may cause damage or mistakenly be blamed for damage. Research has found that despite increases in turkey numbers and …

Investigating The Ecology Of A Rare Species On St. John, Usvi: Reintroducing Solanum Conocarpum In Light Of Climate Change, Cecilia Rogers

Senior Honors Projects, 2010-2019

Approximately two thirds of St. John is National Park territory. However, the land has been threatened with tourism and development, greatly impacting island biodiversity. One species that may become extinct due to this degradation is Solanum conocarpum. S. conocarpum is a rare shrub, endemic to the dry tropical forests of St. John, USVI. This plant is a species of conservation concern and is one of very few native and endemic plants on this island. Very little is known about the ecology and reproduction of S. conocarpum. Most plants are found on the southern half of the island. Recent observations …

Small Mammal Microhabitat Use And Species Composition At A Wildlife Crossing Structure Compared With Nearby Forest, Lindsay Millward, Kristina Ernest

All Master's Theses

Expanding transportation corridors have fragmented ecosystems throughout the world, restricting the movement of organisms or acting as complete connectivity barriers. Wildlife crossing structures (WCS) can increase the permeability of roads, allowing animals to move safely between habitats. Small mammals are especially vulnerable to the effects of reduced connectivity because of their limited mobility; however, few studies have evaluated their use of WCS. This study was conducted at a WCS under I-90 near Snoqualmie Pass, Washington. Our objective was to evaluate the small mammal species composition at the wildlife undercrossing in comparison to adjacent restoration sites and to the nearby forest. …

The Effects Of Forest Degradation On Dna Methylation In Central African Songbirds, Andrew K. Wiegardt

Cal Poly Humboldt theses and projects

Environmentally-induced stress can initiate a molecular response through DNA methylation, which can alter gene expression, thereby serving as a mechanism allowing individuals to acclimate to a changing environment within their lifetime. In addition to DNA methylation, the production and release of corticosterone is a physiological mechanism by which birds can cope with acute environmental stressors. To assess how environmental stress impacted DNA methylation and corticosterone, I collected blood and feather samples from three understory avian species (Alethe castanea, Bleda notatus and Pseudalethe poliocephala), along a disturbance gradient in the lowland Guinean rainforest adjacent to the village of …

"Squeezed Between The Gunshots And The Gentrifiers”: Urban Agriculture In Philadelphia's Kensington Neighborhood, Arianna Hall-Reinhard

Graduate Theses, Dissertations, and Problem Reports (ETD)

Urban agriculture (UA) is part of the broader alternative food movement and a potential avenue through which to “do” food justice work. UA projects in the urban Global North are frequently motivated by social and food justice goals. Despite these guiding ideals, UA projects in America are rife with internal contradictions, including those related to racial inequalities, complex gentrification dynamics, and funding realities. In this paper, I employ the conceptual frameworks of food justice and urban political ecology to consider how gentrification and UA project funding structures affect five specific UA projects in Philadelphia’s Kensington neighborhood. While the loss of …

Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix

Theses and Dissertations

Understanding migratory connectivity is essential for assessing the drivers behind population dynamics and for implementing effective management in migratory species. Genetic markers provide a means to describe migratory connectivity, as well as incorporate population genetic analyses, however genetic markers can be uninformative for species with weak genetic structure. In this study, we evaluate range-wide population genetic structure and migratory connectivity in the prothonotary warbler, Protonotaria citrea, a wetland-dependent neotropical migratory songbird, using high-resolution genetic markers. We reveal regional genetic structure between sampling sites in the Mississippi River Valley and the Atlantic Seaboard with overall weak genetic differentiation among populations …

Multiple-Use Management Of Western U.S. Rangelands: Wild Horses, Wildlife, And Livestock, Rick E. Danvir

Human–Wildlife Interactions

Since 1959, the U.S. Congress has legislated the treatment and management of wild horses (Equus ferus caballus ) and burros (E. asinus ; WHB). While the legislation has ensured WHB a place as western rangeland icons, subsequent congressional actions, in response to public lobbying, have limited federal managers’ ability to manage WHB populations under the U.S. public land multiple-use doctrine. Federal land managers tasked with managing for multiple and competing interests on public lands of the western United States must not only consider WHB habitat requirements, but also wildlife species diversity and livestock grazing. Developing multiple-use management strategies while fulfi …

Environmental Factors Affecting Hatch Success In The Loggerhead Sea Turtle (Caretta Caretta), Mattie J. Whitesell

College of Graduate Studies: Theses & Dissertations

The loggerhead turtle (Caretta caretta) is a species federally listed as “threatened” whose global populations are declining. Georgia Department of Natural Resources conservation protocols for this species require the daily monitoring of nesting activity and permit physical relocation of nests which are at risk of being eroded or flooded by storms and high tides in order to increase hatch success--the proportion of hatched to unhatched eggs. Relocated nests are moved to an area with higher elevation in order to avoid flooding, but other variables such as increased temperature and decreased moisture are introduced when relocating. For years temperature …

Evolution Of Floral Morphology And Symmetry In The Miconieae (Melastomataceae), Maria Gavrutenko

Dissertations and Theses

Analyses of evolution of floral morphology and symmetry broaden our understanding of the drivers of angiosperm diversification. Integrated within a flower, labile floral characters produce different phenotypes that promote variable interactions with pollinators. Thus, investigation of floral evolution may help infer potential historic transitions in pollinator modes and ecological pressures that generated present diversity. This study aims to explore morphological evolution of flowers in Miconieae, a species-rich Neotropical tribe within family Melastomataceae. Despite a constrained floral plan, Melastomataceae manage to achieve a variety of floral traits appealing to diverse pollinator types, with majority of the species requiring specialized “buzz pollination” …

Evolving Reproductive Isolation In The Parasitic Wasp Genus Cotesia, Justin P. Bredlau

Theses and Dissertations

Parasitic wasps are highly diverse and play a major role in suppression of herbivorous pest populations, but relatively little is known of the mechanisms driving their diversity. Molecular studies indicate that cryptic species complexes resulting from adaptations to specific hosts or host-foodplants may be common. The gregarious endoparasitoid, Cotesia congregata (Braconidae), is a model system for understanding parasitic wasp biology. It is reported to attack at least 15 species of sphingid caterpillars, most of which are plant family specialists. Molecular studies have demonstrated genetic differentiation of two host-foodplant complex sources originating from Manduca sexta on tobacco (MsT) and Ceratomia catalpae …

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence …

Potential For Climate Induced Methane Hydrate Dissociation, Graham Macwilliams

Pomona Senior Theses

Methane hydrates are frozen deposits of methane and water found in high pressure or low temperature sediments. When these deposits destabilize, large quantities of methane can be emitted into the atmosphere. This is significant to climate change because methane has 25 times more greenhouse gas potential than Carbon Dioxide. Worldwide, it is estimated there are between 2500 and 10000 gigatons of methane stored in hydrate deposits. This represents more carbon than all fossil fuels on Earth. It is estimated that between 200 and 2000 gigatons of methane are stored in hydrates in Arctic waters acutely vulnerable to greenhouse warming. Over …

Jeweled Spider Flies (Eulonchus Tristis) Are Important Pollinators Of Iris Bracteata, A Rare Siskiyou Mountain Endemic, Jean-Paul E. Ponte

Cal Poly Humboldt theses and projects

Little is known about the pollination biology of the Pacific Coast Irises (Iris: series Californicae, hereafter PCI), especially who visits and pollinates their flowers. In general, Iris flowers are considered bee-pollinated, however, flies in the genus Eulonchus (Acroceridae) are known to visit some PCI members. Therefore, I assessed the relative importance of Eulonchus and other insect visitors to the pollination of a rare PCI species native to the Siskiyou Mountains, I. bracteata.

Methods. I quantified pollinator importance for all flower visitors at sites in northern California and southern Oregon as the product of average visit rate and …

Photosynthetic Activity Under Low Light, Danijela Lonco

Williams Honors College, Honors Research Projects

Are bacteria capable of undergoing oxygenic photosynthesis under low-light conditions inside of caves? Inside of an Australian cave, Chlorophyll f was recently discovered. This chlorophyll pigment was found to demonstrate the capability for photosynthesis, suggesting that Chlorophyll f extends the spectrum of usable light needed for oxygenic photosynthesis (Lars, 2015). Due to the findings in this study, a team went to Carlsbad Caverns to see if there were any bacteria capable of undergoing oxygenic photosynthesis under low light.

Comparing Bird Communities Within Shrubby Transmission Line Rights-Of-Way Managed By Mowing Or By Selective Herbicide Application In Maine And New Hampshire, Kathleen P. Wadiak

Honors Theses and Capstones

In the northeastern U.S., thousands of miles of shrub-dominated transmission line rights-of-way (ROW) extend across the landscape and provide some of the largest and most stable shrubland habitats in the region. These ROW are used as nesting and post-fledging habitat by the region’s entire community of shrubland-dependent songbirds, but evidence for how ROW are used by songbirds that require other habitats for nesting is lacking. Mist-netting surveys conducted in regenerating clearcuts indicate that adult and fledgling mature-forest songbirds comprise a large proportion of the bird community in clearcuts during the post-fledging portion of the breeding season, a time when juvenile …

Competing Activities As Measures Of Fear And Vigilance, Ferenc Mónus

Animal Sentience

In animal behavioural research on vigilance, visual signs of alertness are usually used to estimate perceived risk (an internal “fear” state) of free-ranging animals. Different measures of vigilance and competing activities (e.g., predator vigilance, conspecific vigilance, feeding, food handling) provide clues for better understanding vigilance behaviour. How efficiently does an animal in a vigilant/non-vigilant posture devote attention to threats or invest in other activities, such as searching for or handling food? Several species regularly withdraw to a sheltered spot when feeding in an abundant food patch, spending short periods in complete safety. Frequencies of feeding interruptions or false-alarm flights provide …

Lewis’S Woodpecker Nest Success And Habitat Selection In Cottonwood Floodplain Versus Burned Conifer Forests, William M. Blake

Graduate Student Theses, Dissertations, & Professional Papers

Breeding habitat selection influences reproductive outcomes. Habitat selection may be adaptive and benefit populations, but it can also be maladaptive with negative consequences for populations. Understanding habitat selection and its influence on reproductive success, especially in species of concern, is critical for effective management. Lewis’s Woodpecker (Melanerpes lewis) is a Species of Concern that has experienced national population declines. We studied its abundance and reproductive success in two commonly selected breeding forest types (i.e., cottonwood floodplain and mixed-conifer burned), and nest-site characteristics (nest availability, food availability, and vegetation attributes) that have the potential to yield strong differences in …

Framing Contemporary U.S. Wild Horse And Burro Management Processes In A Dynamic Ecological, Sociological, And Political Environment, J. Derek Scasta, Jacob D. Hennig, Jeffrey L. Beck

Human–Wildlife Interactions

The Wild Free-Roaming Horses and Burros Act (WFRHBA) of 1971 established all “unbranded or unclaimed” equids on U.S. public lands as “living symbols of the historic and pioneer spirit of the West.” Today, >72,000 feral horses (Equus ferus caballus) and burros (E . asinus ; WHB) live on western U.S. public rangelands. The number of WHBs exceeds the Bureau of Land Management’s maximum Appropriate Management Level (AML) of 26,715 by a factor of approximately 2.7 and has nearly doubled from 2007–2015. The AML was set to balance WHB numbers with rangeland health and support other uses such as wildlife habitat …

The Three Creeks Allotment Consolidation: Changing Western Federal Grazing Paradigms, Taylor Payne

Human–Wildlife Interactions

The federal government owns approximately 47% of all land in the western United States. In the state of Utah, about 64% of the land base is managed by the federal Bureau of Land Management (BLM) and the U.S. Forest Service (USFS). The government has historically issued permits to owners of private lands to allow the owners to graze their livestock on public lands. The permits (allotments) are generally of 10-year duration and allow for an annual season of use. In some cases, continued and repeated historical annual grazing practices may not be ideal for permit holders and their communities nor …

The Dynamic Nature Of Forage Preference And Microhistological Atlas, John J. Henderson

Dissertations, Master's Theses and Master's Reports

Moose, Alces alces, are among the most iconic species in the northern circumpolar temperate forests. Multiple factors influence moose density. Winter is a time of severe dietary stress for moose because deciduous trees are leafless and available forage is limited to conifers with high plant secondary metabolites or low-energy deciduous twigs. Forage preference depends on the intrinsic forage properties, abundance of forage and environmental stressors. These stressors include predation risk and severity of climate that affect forage efficiency. We examined forage preference of moose on Isle Royale National Park during winter over a ten-year period. Diet was divided into …

Ecological Implications Of Foraging And Life-History In Three Cold-Adapted Species, Andrew Von Duyke

Dissertations, Master's Theses and Master's Reports

This research investigates the ecology of: ringed seals (Pusa hispida), moose (Alces alces), and bowhead whales (Balaena mysticetus). Each of these species draws upon specialized strategies to meet the physical demands of life in their extreme environments. However, they are currently experiencing unprecedented changes in their habitats. This work adds to what is known about the behavior, physiology, and population dynamics of cold-adapted species—providing insights of value for an improved understanding of foraging and life-history theory, and informing conservation and ecosystem monitoring efforts. Chapter 1 provides a brief introduction to the scope of work …

Molecular And Evolutionary Analysis Of Cyanobacterial Taxonomic Methods, Chelsea Denise Villanueva

UNF Graduate Theses and Dissertations

Cyanobacteria are a group of photo-oxygenic bacteria found in nearly every ecosystem, but much cyanobacterial diversity, in various habitats, has yet to be explored. Cyanobacteria are often conspicuous components of photosynthetic flora, providing significant carbon and nitrogen inputs to surrounding systems. As possible primary colonizers of stone substrates not native to this region, cyanobacteria isolated from headstones may provide biogeographically informative data. An exploratory study of lichen-dominated microbial consortia, growing on headstones, was conducted to isolate and identify novel microaerophytic cyanobacteria, and resulted in the establishment of four novel cyanobacterial taxa. Phylogenetic analyses of photobionts in one tripartite lichen revealed …

The Effects Of The Red Tide Producing Dinoflagellate, Karenia Brevis, And Associated Brevetoxins On Viability And Sublethal Stress Responses In Scleractinian Coral: A Potential Regional Stressor To Coral Reefs, David A. Reynolds

UNF Graduate Theses and Dissertations

Coral cover is in decline on a global scale, with increased mortality events being attributed to a number of global and regional stressors. While the impacts of global stressors (e.g. sea surface temperature rise, ocean acidification) are well documented, there is growing interest in identifying and understanding the impacts of regional stressors. The reason for this change in focus is that regional stressors can often work in combination, sometimes synergistically, with global stressors and that stressors on a regional scale tend to be more easily mitigated by management practices. One regional stressor that impacts a myriad of marine organisms in …