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Combining Isotopic And Genetic Analyses To Quantify Microbial Facilitation Of Recalcitrant Resource Use By Terrestrial And Aquatic Consumers, Alexi Christina Besser
Combining Isotopic And Genetic Analyses To Quantify Microbial Facilitation Of Recalcitrant Resource Use By Terrestrial And Aquatic Consumers, Alexi Christina Besser
Biology ETDs
Quantifying the flow of energy and nutrients through food webs is foundational to understanding the structure and function of ecosystems. Here, I utilize the stable carbon and nitrogen isotope analysis of individual amino acids to trace the movement of essential amino acids through terrestrial and freshwater food webs in New Mexico, USA. I first explore isotopic patterns among co-occurring terrestrial plants and aquatic algae. I then combine this molecular isotopic approach with 16S and 18S rRNA sequencing to demonstrate the importance of gut microbiota as sources of essential amino acids to wild mammalian hosts. Next, I explore the roles of …
Reconstructing Energy Flow Through Modern And Historical Marine Communities: Insights From Amino Acid Isotope Analysis, Emma A. Elliott Smith
Reconstructing Energy Flow Through Modern And Historical Marine Communities: Insights From Amino Acid Isotope Analysis, Emma A. Elliott Smith
Biology ETDs
The fundamental currency of life is energy. Organisms need energy to grow, to survive and to reproduce. Understanding the acquisition of energy by consumers is thus a foundational aspect of biological research. This is especially important in the modern era, as impacts of ongoing anthropogenic effects will be mediated or amplified through food webs. Here, I explore how isotopic analysis of individual amino acids – a technique new to ecological studies – can be used to trace energy flow through animal communities in modern and ancient time periods. In particular, I focus on kelp forest food webs, which are nearshore …
Spatial And Temporal Patterns Of Arctic Nearshore Fish Community And Food Web Structures, Mark B. Barton
Spatial And Temporal Patterns Of Arctic Nearshore Fish Community And Food Web Structures, Mark B. Barton
FIU Electronic Theses and Dissertations
Climate change and increasing anthropogenic activities are causing rapid changes to environmental and ecological processes in the Arctic Ocean. To better understand these changes, scientists have increased research efforts in these regions, but to date the number of studies on Arctic nearshore habitats are lacking. My dissertation responds to the paucity of information and investigates patterns in Arctic nearshore fish communities and food webs to gain insight to how these ecosystems may shift as these changes continue. I used multivariate statistical analysis to examine patterns in community structure and composition to determine that Arctic nearshore fish communities are largely driven …
Using D13c, D15n, And D2h To Better Understand The Ecology Of Green Sea Turtles, Laura Pagès Barceló
Using D13c, D15n, And D2h To Better Understand The Ecology Of Green Sea Turtles, Laura Pagès Barceló
Biology ETDs
Many green sea turtle populations are slowly recuperating from a recent severe decline due to anthropogenic factors including human consumption and mortality related to the fishing industry. Despite being charismatic animals that have been extensively studied, there is still a limited understanding of their feeding strategies and diet plasticity. This research explores the use of hydrogen isotopes in marine ecosystems to better understand green sea turtle ecology. This study is presented in two chapters: I first examined the trophic discrimination factor (D2HNET) for hydrogen isotope (d2H) as a tool to correct hydrogen isotope data …
Small Mammal Diversity, Rattlesnake Demographics, And Resource Utilization In The Great Basin: Implications For Management And Stable Isotope Proxies, Bryan T. Hamilton
Small Mammal Diversity, Rattlesnake Demographics, And Resource Utilization In The Great Basin: Implications For Management And Stable Isotope Proxies, Bryan T. Hamilton
Theses and Dissertations
Plant carbon isotopes were used to track assimilation of riparian resources by small mammals. Voles and shrews derived significant portions of their carbon from riparian vegetation. Deer and harvest mice were abundant in riparian habitat but assimilated little riparian vegetation indicating that the riparian corridor provided resources other than food. This is first use of stable carbon isotopes to trace riparian resources into a vertebrate community. Conifer encroachment in sagebrush ecosystems negatively affects many wildlife populations. Conifer removal is recommended across millions of hectares in the Great Basin. However the effects of conifer encroachment and conifer removal are unknown for …
Connecting The Dots: Stopover Strategies Of An Intercontinental Migratory Songbird In The Context Of The Annual Cycle, Kristina Paxton, Frank R. Moore
Connecting The Dots: Stopover Strategies Of An Intercontinental Migratory Songbird In The Context Of The Annual Cycle, Kristina Paxton, Frank R. Moore
Faculty Publications
The phases of the annual cycle for migratory species are inextricably linked. Yet, less than five percent of ecological studies examine seasonal interactions. In this study, we utilized stable hydrogen isotopes to geographically link individual black-and-white warblers (Mniotilta varia) captured during spring migration with breeding destinations to understand a migrant's stopover strategy in the context of other phases of the annual cycle. We found that stopover strategy is not only a function of a bird's current energetic state, but also the distance remaining to breeding destination and a bird's time-schedule, which has previously been linked to habitat conditions experienced …
How Diverse Detrital Environments Influence Nutrient Stoichiometry Between Males And Females Of The Co-Occurring Container Mosquitoes Aedes Albopictus, Ae. Aegypti, And Culex Quinquefasciatus, Donald A. Yee, Michael G. Kaufman, Nnaemeka F. Ezeakacha
How Diverse Detrital Environments Influence Nutrient Stoichiometry Between Males And Females Of The Co-Occurring Container Mosquitoes Aedes Albopictus, Ae. Aegypti, And Culex Quinquefasciatus, Donald A. Yee, Michael G. Kaufman, Nnaemeka F. Ezeakacha
Faculty Publications
Allocation patterns of carbon and nitrogen in animals are influenced by food quality and quantity, as well as by inherent metabolic and physiological constraints within organisms. Whole body stoichiometry also may vary between the sexes who differ in development rates and reproductive allocation patterns. In aquatic containers, such as tree holes and tires, detrital inputs, which vary in amounts of carbon and nitrogen, form the basis of the mosquito-dominated food web. Differences in development times and mass between male and female mosquitoes may be the result of different reproductive constraints, which could also influence patterns of nutrient allocation. We examined …
Isotopic Incorporation Rates And Discrimination Factors In Mantis Shrimp Crustaceans., Maya Devries, Carlos Del Rio, Tate Tunstall, Todd Dawson
Isotopic Incorporation Rates And Discrimination Factors In Mantis Shrimp Crustaceans., Maya Devries, Carlos Del Rio, Tate Tunstall, Todd Dawson
Faculty Publications, Biological Sciences
Stable isotope analysis has provided insights into the trophic ecology of a wide diversity of animals. Knowledge about isotopic incorporation rates and isotopic discrimination between the consumer and its diet for different tissue types is essential for interpreting stable isotope data, but these parameters remain understudied in many animal taxa and particularly in aquatic invertebrates. We performed a 292-day diet shift experiment on 92 individuals of the predatory mantis shrimp, Neogonodactylus bredini, to quantify carbon and nitrogen incorporation rates and isotope discrimination factors in muscle and hemolymph tissues. Average isotopic discrimination factors between mantis shrimp muscle and the new diet …
Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga
Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga
Graduate Theses and Dissertations
Positive associations among species have contributed to the maintenance of biodiversity. These interactions are typically studied in pairwise fashion where two interacting organisms are the focus. This dissertation uses network theory to analyze positive plant-ant associations in three Neotropical forests. Obligate plant-ant mutualisms were used, where plants host the ants in domatia and provide food bodies while the ants protect the plants and can feed them. A network approach was used to depict all obligate plant-ant interactions within a community. The main questions asked at the community level were: 1) Do network structure and levels of specialization change geographically and, …
Consequences Of Vegetation Change On The Dynamics Of Labile Organic Matter And Soil Nitrogen Cycling In A Semiarid Ecosystem, Toby D. Hooker
Consequences Of Vegetation Change On The Dynamics Of Labile Organic Matter And Soil Nitrogen Cycling In A Semiarid Ecosystem, Toby D. Hooker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Sagebrush-dominated ecosystems are being transformed by wildfire, rangeland improvement techniques, and exotic plant invasions. These disturbances have substantial effects on the composition and structure of native vegetation, but the effects on ecosystem C and N dynamics are poorly understood. To examine whether differences in dominant vegetation affect the quantity and quality of plant organic matter inputs to soil, ecosystem C and N pools and rates of plant turnover were compared among historically grazed Wyoming big sagebrush, introduced perennial crested wheatgrass, and invasive annual cheatgrass communities. Since low soil moisture during the summer may inhibit the microbial colonization of plant detrital …
Using Stable Isotopes To Assess Population Structure And Feeding Ecology Of North Pacific Humpback Whales (Megaptera Novaeangliae), Briana Witteveen
Using Stable Isotopes To Assess Population Structure And Feeding Ecology Of North Pacific Humpback Whales (Megaptera Novaeangliae), Briana Witteveen
Electronic Theses and Dissertations
The North Pacific humpback whale (Megaptera novaeangliae) is a wide-ranging baleen whale species with a complex life history and population structure. As seasonal migrants, humpback whales are known to inhabit cooler, high-latitude waters when foraging and low-latitudes for mating and calving. Beyond this general migratory pattern, a number of demographic characteristics including, abundance, distribution, seasonal occurrence, and prey preferences remain unknown or poorly described. A complete understanding of humpback whale ecology is therefore lacking. Many methods used to explore these aspects of cetacean ecology are either prohibitively expensive or limited in the scope of what can be learned from their …
Stabel Isotope Turnover Rates And Diet-Tissue Discrimination In The Skin Of West Indian Manatees: Implcations For Evaluating Their Feeding Ecology And Habitat Use, Christy Alves
Electronic Theses and Dissertations
The West Indian manatee (Trichechus manatus) is an herbivorous marine mammal that occupies freshwater, estuarine, and marine habitats. Despite being considered endangered, relatively little is known about the feeding ecology of either of the two recognized subspecies, the Florida manatee (T.m. latirostris) and Caribbean or Antillean manatee (T.m. manatus). A better understanding of their respective feeding preferences and habitat use is essential to establish criteria on which conservation plans can be based. The present study expands on previous work on manatee feeding ecology by both assessing the application of stable isotope analysis to manatee tissue and providing critical baseline parameters …