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Biology

Theses/Dissertations

2020

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Full-Text Articles in Ecology and Evolutionary Biology

A Cophylogenetic Analysis Of Fungus Gardening Ants And Their Symbiotic Fungi, Katherine Beigel Dec 2020

A Cophylogenetic Analysis Of Fungus Gardening Ants And Their Symbiotic Fungi, Katherine Beigel

Biology Theses

Fungus-growing ants (Tribe Attini) and their fungal cultivars share a 50-million-year coevolutionary history. Large scale phylogenetic analyses depict a strong co-phyletic signal among ants and their farmed fungi yet fungus sharing among unrelated ant lineages is somewhat widespread. An overview of sharing has been hampered by a lack of genetic markers that exhibit intraspecific variation and surveys across geographic regions. For example, previous studies have shown similar sequences of the internal transcribed spacer (ITS) region of fungus in different species of Trachymyrmex, suggesting that these ant species are farming the same fungal clone. To examine whether this was a …


Influence Of Testosterone On Male-Male Competition In The Red-Sided Garter Snake, Thamnophis Sirtalis Parietalis, Isabella M. G. Bukovich Dec 2020

Influence Of Testosterone On Male-Male Competition In The Red-Sided Garter Snake, Thamnophis Sirtalis Parietalis, Isabella M. G. Bukovich

Senior Honors Projects, 2020-current

Female mimicry in the red-sided garter snake, Thamnophis sirtalis parietalis, is described in several well-studied evolutionary advantages, but an aspect that remains elusive is how reproductive traits are linked to the 3-fold higher circulating androgens in males with this phenotype. In this study, we implanted male garter snakes (n=15 per group) with either a blank implant (SHAM; control) or a T implant, the latter simulating the female mimic phenotype. Following simulated low-temperature dormancy, males were scored for courtship intensity over three days of behavioral trials with females housed in the same facility. Males were sacrificed, and sperm were collected …


Exposing Lettuce Plants To Cyanobacteria In A Closed Hydroponics System To Reduce Cyanobacterial Growth And Production, Emily Eberly Dec 2020

Exposing Lettuce Plants To Cyanobacteria In A Closed Hydroponics System To Reduce Cyanobacterial Growth And Production, Emily Eberly

Honors Projects

Sandusky Bay is largely populated by cyanobacterial algal blooms, mainly formed by Planktothrix. Fertilizers containing nitrogen and phosphorus run from agricultural lands into the bay, building up excess nutrients forming eutrophic waters. The Planktothrix feed off these nutrients and grow into algal blooms. To determine a potential solution to the growth of these blooms, I implemented a hydroponics system involving Lactuca Sativa for analysis of Planktothrix growth and productivity. Four different nutrient conditions were added to a Planktothrix-only solution and a solution growing Planktothrix with the lettuce in the hydroponics system. The four conditions consisted of no nutrient …


Impact Of Endangered Animal Protection Rights, Policies, And Practices On Zoonotic Disease Spread, Daniella Fedak-Lengel Dec 2020

Impact Of Endangered Animal Protection Rights, Policies, And Practices On Zoonotic Disease Spread, Daniella Fedak-Lengel

Honors Projects

Building on field research in Costa Rica and Belize, this honors project analyzes environmental and endangered animal protection policies, rights, and practices in Central America and the Caribbean, and assesses the impact of veterinary science and biological research and practice, particularly conservation biology, on animal welfare concerns. Informed by the recent surge in awareness regarding zoonoses and zoonotic disease transmission, prevention and control, resulting from the current global pandemic of SARS-CoV-2, the project assesses the need for new and innovative types of collaboration, particularly involving conservation biologists, environmental scientists, public health experts, law and policy makers, and global trade and …


Residency, Diel Movement, And Tidal Patterns Of Large Juvenile Bull Sharks (Carcharhinus Leucas) In Winyah Bay, Sc, Jeremy Lee Arnt Dec 2020

Residency, Diel Movement, And Tidal Patterns Of Large Juvenile Bull Sharks (Carcharhinus Leucas) In Winyah Bay, Sc, Jeremy Lee Arnt

Electronic Theses and Dissertations

No abstract provided.


Analysis Of Seasonal Changes In Thermal Stress Resilience And Innate Immunity In The Temperate Coral, Astrangia Poculata, From Future Climate Impacts, Tyler Eugene Harman Dec 2020

Analysis Of Seasonal Changes In Thermal Stress Resilience And Innate Immunity In The Temperate Coral, Astrangia Poculata, From Future Climate Impacts, Tyler Eugene Harman

Masters Theses

Over the years, global warming has had a devastating effect on coral reef ecosystems. Anthropogenic influences have caused significant increases in greenhouse gases, with a subsequent increase in solar radiation held within Earth’s atmosphere leading to increasing global temperatures. The increasing temperatures from concurrent increases in greenhouse gases impact fragile marine ecosystems such as coral reefs, which require particular environmental parameters such as temperature in order to survive and maintain a diverse ecosystem in which many marine species rely on. These increases in temperature exacerbate phenomena such as bleaching events and coral disease, drastically impacting coral on a global scale …


Soil Response To Fire Frequency In The Northern Columbia Basin Sagebrush Steppe, Leslie C. Nichols Dec 2020

Soil Response To Fire Frequency In The Northern Columbia Basin Sagebrush Steppe, Leslie C. Nichols

Boise State University Theses and Dissertations

Fire is one of the most significant disturbances in an ecosystem, as it is capable of altering the physical, chemical, and biological properties of soil, and the fire frequency in semi-arid ecosystems is increasing. These changes can potentially alter plant-soil feedbacks that may affect post-fire recovery of the native plant and soil communities and lead to an ecosystem state change. However, there is much uncertainty about the magnitude of change as soils are exposed to more fires, because soil recovery and changes in fire severity following a first fire mediate the impact of successive fires on soil properties. To improve …


The Effects Of Multiple Stressors On Stream Communities: The Convergence Of Drought, Nutrient Pollution, And Invasive Species, Robert Joseph Fournier Iii Dec 2020

The Effects Of Multiple Stressors On Stream Communities: The Convergence Of Drought, Nutrient Pollution, And Invasive Species, Robert Joseph Fournier Iii

Graduate Theses and Dissertations

Freshwater systems experience multi-faceted degradation from a variety of ecological and environmental stressors. Three common stressors in these systems, drought, nutrient pollution, and invasive species, have wide-ranging effects on stream population- community- and ecosystem dynamics. We have a broad understanding of how each of these stressors works to influence stream systems independently. However, we still know relatively little about if, and how, these stressors might interact when they co-occur. Though drought is a natural part of many stream systems, all three of these stressors can be exacerbated or facilitated by anthropogenic actions. Accordingly, as human population and resource use continue …


Neogene And Quaternary Events Shaped Diversification And Speciation In Bhutanese Rheophilic Fishes Of The Family Nemacheilidae (Cypriniformes) And Sisoridae (Siluriformes), Karma Wangchuk Dec 2020

Neogene And Quaternary Events Shaped Diversification And Speciation In Bhutanese Rheophilic Fishes Of The Family Nemacheilidae (Cypriniformes) And Sisoridae (Siluriformes), Karma Wangchuk

Graduate Theses and Dissertations

Biogeography of the Himalayan region [to include the Qinghai-Tibetan Plateau (QTP)] evolved over a ~30M year span, catalyzed by the collision of the Indian and Eurasian plates. The resulting uplift produced major ecological and climatic effects, that in turn drove the diversification of biodiversity. As a result, the QTP is designated as a global biodiversity hotspot particularly vulnerable to cumulative climatic effects, including shrinking distributions, declining numbers, and local extinctions. Understanding how the biodiversity within the Himalaya/ QTP was established and maintained is a necessary first step in prioritizing conservation efforts.

Fishes in global montane regions, such as the Himalaya, …


Assessment Of Genetic Diversity In Largetooth Sawfish, Pristis Pristis, Populations Over The 20th Century, Ann Fearing Dec 2020

Assessment Of Genetic Diversity In Largetooth Sawfish, Pristis Pristis, Populations Over The 20th Century, Ann Fearing

Master's Theses

The Critically Endangered Largetooth Sawfish, Pristis pristis, experienced global declines in range and abundance over the past century and Australia is now their last stronghold. This research aimed to understand whether these declines have been accompanied by a reduction in levels of genetic diversity. Using P. pristis tissue samples sourced from natural history specimens, three fragments (616-bp, 386-bp, 141-bp) in the mitochondrial DNA (mtDNA) control region were PCR-amplified. At each fragment, significant genetic structure was found in P. pristis overall (ΦST=0.946, N=9; 0.813, N=54; 0.771, N=99). The Indo-West Pacific and Atlantic/Eastern Pacific each harbor genetically distinct lineages of …


Effects Of Long-Term Variation In Temperature On Reproductive Phenology In A Population Of Eastern Bluebirds (Sialia Sialis), Paul Pleiman Dec 2020

Effects Of Long-Term Variation In Temperature On Reproductive Phenology In A Population Of Eastern Bluebirds (Sialia Sialis), Paul Pleiman

Graduate Theses and Dissertations

This study investigates the relationship between multiple temperature variables, to include annual and pre-lay date temperatures with first-egg and mean first-egg lay dates of the eastern bluebird at the Warner Parks in Nashville, Tennessee, USA. Data is collected by citizen scientists for the Eastern Bluebird Nesting Box Project while visiting artificial nest boxes throughout the park and recording observations made during the breeding season. Temperature data is retrieved from the Northwest Alliance for Computational Science and Engineering’s Parameter-elevation Regressions on Independent Slopes Model (PRISM) Climate Group, based at Oregon State University. The analyses showed no correlation between annual or pre-lay …


Fish And Macroinvertebrate Response To Restoration And Conservation Efforts, Madison C. Cogar Dec 2020

Fish And Macroinvertebrate Response To Restoration And Conservation Efforts, Madison C. Cogar

MSU Graduate Theses

Fish and macroinvertebrate response to restoration and conservation efforts varies in regards to the size and structure of the system (e.g. headwater streams in WV versus large rivers such as the Mississippi River). This project reviews fish and macroinvertebrate rebound in treated acid mine drainage (AMD) streams in WV as well as macroinvertebrate drift patterns in the Mississippi and Missouri Rivers. AMD is a product of a chemical reaction resulting in an acidic water outflow from mining sites, which may harm aquatic life. As a response, passive AMD treatment systems have been installed. I tested the effectiveness of remediation by …


The Occurrence Of Microplastics Among Freshwater Fish Guilds In A South Carolina Reservoir, Chasity Rae Moore Dec 2020

The Occurrence Of Microplastics Among Freshwater Fish Guilds In A South Carolina Reservoir, Chasity Rae Moore

Graduate Theses

No abstract provided.


Spatial Use By Mammals Within Two State Parks In The Ozarks National Scenic Riverways, Benjamin Aaron Smith Dec 2020

Spatial Use By Mammals Within Two State Parks In The Ozarks National Scenic Riverways, Benjamin Aaron Smith

MSU Graduate Theses

A mammalian species inventory with comparisons between sampled sites was conducted via multiple methodologies to document presence of mammals at two Missouri state parks within the Ozark National Scenic Riverways. Camera traps, small mammal traps, acoustic detectors, and mist nets were used to detect species at the parks, and species similarity indices and occupancy analyses were used to discern use of space. A mammalian inventory was compiled for each area of inquiry. Greater diversity was found at the park with more variable habitat types. Bat activity was more in the park with a known hibernaculum, though species specific activity differed …


Drivers Of Rickettsial Pathogen Transmission And Spillover In Local Tick Populations In Southeastern Virginia, Alexandra Cumbie Dec 2020

Drivers Of Rickettsial Pathogen Transmission And Spillover In Local Tick Populations In Southeastern Virginia, Alexandra Cumbie

Biomedical Sciences Theses & Dissertations

Cases of spotted fever group rickettsiosis are becoming more prevalent in the United States. In Virginia, there are three human-biting ticks which are largely responsible for the spread of rickettsial pathogens and the increase in disease cases. These species include Dermacentor variabilis, Amblyomma americanum, and Amblyomma maculatum; all of which are vectors of rickettsial agents to vertebrate hosts. These species are sympatric as adults and have the potential to share large and small mammal hosts. Their interactions on and off host and their associated rickettsiae were the focus of this dissertation work. Amblyomma americanum is the vector …


Assessment Of Factors Influencing Migratory Landbird Use Of Forested Stopover Sites Along The Delmarva Peninsula During Autumn Migration, J. Andrew Arnold Dec 2020

Assessment Of Factors Influencing Migratory Landbird Use Of Forested Stopover Sites Along The Delmarva Peninsula During Autumn Migration, J. Andrew Arnold

Biological Sciences Theses & Dissertations

Autumn migration is a time when billions of birds move from breeding grounds in North America to wintering grounds in Central and South America, with many individuals relying on stopover habitats en route for resting and refueling purposes. These stopover sites are critical to the survival of the hundreds of species of migratory landbirds that migrate annually, and thus identifying important stopover sites is a high priority for conserving such taxa. The Delmarva Peninsula; a coastal region of Delaware, Maryland, and Virginia along the mid-Atlantic flyway; consists of forested habitats with ample food and shelter that likely serves as quality …


Cross-Host Correlations And Multivariate Effects Of Herbivore Specialization, Daniel J. Zydek Nov 2020

Cross-Host Correlations And Multivariate Effects Of Herbivore Specialization, Daniel J. Zydek

USF Tampa Graduate Theses and Dissertations

The distribution of insect herbivores among plant hosts is largely nonrandom: most herbivores have limited sets of hosts within one or a few plant families. This host use specialization is reinforced by traits that confer differential fitness across host plant species. Classic explanations for herbivore specialization predict that evolutionary trade-offs reinforce these relationships by imposing costs in the form of reduced potential fitness on alternative hosts, due to negative genetic correlations in fitness across hosts. This prediction that trade-offs constrain host use in herbivores can be tested with experimental evolution, by showing the direct evolutionary effects of host manipulation on …


Quantifying Structure And Variation In Complex Phylogenetic Data, Genevieve Geraldine Mount Nov 2020

Quantifying Structure And Variation In Complex Phylogenetic Data, Genevieve Geraldine Mount

LSU Doctoral Dissertations

Identifying the source and structure of variation in nature is crucial to understanding fundamental aspects of evolution. Despite a recent plethora of genetic and morphological data, many interesting questions about the relationships between different groups remain unresolved. My dissertation evaluates three approaches for identifying and quantifying the variation within phylogenetic datasets. Characterizing variation within datasets and across analytical methods gives insight into biologically interesting characters, unusual evolutionary processes, and areas for model improvement.

Network-based community detection approaches offer a powerful tool to describe variation in phylogenetic signal across the genome (i.e., gene tree variation). In Chapter 2, I investigate the …


Evolution Of Green Blood In New Guinea Lizards: Phylogenomics, Biogeography, And Comparative Genomics, Zachary Rodriguez Nov 2020

Evolution Of Green Blood In New Guinea Lizards: Phylogenomics, Biogeography, And Comparative Genomics, Zachary Rodriguez

LSU Doctoral Dissertations

Non-model organisms with evolutionary novelties and complex distributions can provide valuable insight into the mechanisms underlying biological diversity. Green blood is one of the most unusual vertebrate physiologies and has repeatedly evolved in lizards from the megadiverse island of New Guinea. An unusually high concentration of the toxic green bile pigment biliverdin causes the green coloration of these lizards' blood, muscles, and bones. This dissertation uncovered the complex history of this novel trait (Chapter 2), identified protein-coding sequences that underlie green blood in lizards (Chapter 3), and explored evolutionary processes that drive genetic diversity in high-elevation lizards. To accurately trace …


Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes Nov 2020

Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes

Biology ETDs

Few studies have examined inoculum potential of ectomycorrhizal fungi (EMF) in the absence of plant hosts, yet persistence of these fungi may be paramount to resilience of Pinus edulis and other mycorrhizal plant species. We conducted a study in which seven sites were selected in northwestern New Mexico with known dates of P. edulis extirpation and a lack of regeneration. Age classes included: two sites extirpated 10-20 years ago, two extirpated 55-65 years ago, two extirpated 500+ years ago, and one extirpated 11,000+ years ago. At each site, two plots were paired: an extirpated plot and the nearest live adult …


Spatio-Temporal Dynamics Of Fungal Communities And Their Effects On Plants, Kel Cook Nov 2020

Spatio-Temporal Dynamics Of Fungal Communities And Their Effects On Plants, Kel Cook

Biology ETDs

Fungi perform several critical functions in the environment. Spatiotemporal distributions of fungal communities will mediate when and where these functions happen and how they vary across the landscape. I first explored tropical tree canopy fungal community variation at small spatial scales and documented near total turnover of fungi across sub-meter distances and among adjacent substrates. The second chapter analyzed fungal turnover over the course of three years, where community stability was driven primarily by abundant fungi. In the third chapter, I tested effects of the environment, including host plant and habitat, on canopy fungal communities and found only small effects, …


Genetic Basis Of Hybrid Sterility Between Drosophila Pseudoobscura And D. Persimilis, Alannah J.P. Mattice Oct 2020

Genetic Basis Of Hybrid Sterility Between Drosophila Pseudoobscura And D. Persimilis, Alannah J.P. Mattice

Electronic Thesis and Dissertation Repository

Speciation is the underlying process that leads to formation of new species, and therefore is the basis of biodiversity. Genes involved in each stage of speciation, such as those involved in interspecies sterility, remain elusive. Male hybrid sterility and postzygotic isolation between Drosophila pseudoobscura and D. persimilis was examined in this study through backcrossing of female hybrids into each parental line (introgression), selecting for a sterile sperm phenotype, needle-eye sperm. Sperm phenotypes did not separate through backcrossing; instead, males presented with multiple sperm phenotypes. A relationship between the phenotypes observed and the potential genes involved was examined through whole genome …


Characterizing The Diversity Of The Eukaryotic Microbiome In Marine Crustacean Zooplankton., Rose-Lynne Savage Oct 2020

Characterizing The Diversity Of The Eukaryotic Microbiome In Marine Crustacean Zooplankton., Rose-Lynne Savage

Electronic Thesis and Dissertation Repository

Understanding zooplankton productivity is critical for modeling marine food web function, of which one poorly known factor is the influence of zooplankton symbionts. Zooplankton protist symbiont diversity is underestimated due to the limited surveys and techniques previously used. Using 18S V4 metabarcoding, I characterized the eukaryotic microbiomes associated with crustacean zooplankton from the northern Strait of Georgia, BC. Apostome ciliates were most abundant in all hosts except for cyclopoid copepods, which were dominated by Syndiniales. Most symbiont lineages were more abundant in one or two hosts, suggesting some degree of host preference. Microbiome data also provided information on diet, confirming …


Great Lakes Snake: Estimating The Occupancy And Detection Probabilities Of The Eastern Massasauga Rattlesnake (Sistrurus Catenatus), Arin June Thacker Sep 2020

Great Lakes Snake: Estimating The Occupancy And Detection Probabilities Of The Eastern Massasauga Rattlesnake (Sistrurus Catenatus), Arin June Thacker

Masters Theses

Detailed knowledge of a species’ range and distribution is important for understanding species persistence and developing species management plans. This issue is particularly pronounced in threatened species with wide-spread range and a low detectability in their natural environment, as surveying and successfully encountering this type of species is oftentimes difficult. One such species is the eastern massasauga rattlesnake (Sistrurus catenatus), a smallbodied pit viper with a distribution centered around the Great Lakes region. We used singleseason occupancy modeling in order to reassess the status of historic massasauga occurrences. We evaluated factors affecting eastern massasauga detection probability from a …


Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams Sep 2020

Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams

Master's Theses

Planktonic larvae of marine organisms are increasingly being exposed and required to respond to a changing physical environment. Adult sea urchins occupy both intertidal and subtidal waters and broadcast spawn gametes into the water column to contend with variable physical conditions. To answer how populations of invertebrates residing at different depths adequately prepare their offspring to cope with different levels of ultraviolet radiation (UVR), we collected adult purple sea urchins, Strongylocentrotus purpuratus, from four sites (two intertidal and two subtidal (~15 m deep)) on the central coast of CA to compare UV tolerance in offspring. Our measurements of UVA …


Genetic Population Structure And Microbiome Of German Cockroaches In Urban Environments, Xueyang Fan Aug 2020

Genetic Population Structure And Microbiome Of German Cockroaches In Urban Environments, Xueyang Fan

Dissertations

Pests of human habitats may harbor and disperse pathogens that cause human disease. One such pest is the German cockroach (Blattella germanica), which is known to harbor numerous pathogens, including Klebsiella and Pseudomonas. The aim of this study is to reveal the importance of the German cockroach as a potential vector of human medically important diseases. To do so, this study investigates German cockroach population structure and their associated bacterial microbiome in urban residential environments. Ninety German cockroaches are collected from three residential apartment buildings in three New Jersey cities. Samples are caught by glue traps and stored at -20°C. …


Distributions And Abundances Of The Red Tide Dinoflagellate Alexandrium Catenella In The Eastern Gulf Of Maine And Bay Of Fundy In Relation To Diatoms In June, July And August Of 2019, Kimberly Lina D'Adamo Aug 2020

Distributions And Abundances Of The Red Tide Dinoflagellate Alexandrium Catenella In The Eastern Gulf Of Maine And Bay Of Fundy In Relation To Diatoms In June, July And August Of 2019, Kimberly Lina D'Adamo

Electronic Theses and Dissertations

A series of three oceanographic survey cruises were conducted in June, July, and August of 2019 in the northeastern Gulf of Maine and Bay of Fundy. Surface water samples were collected and analyzed for enumerations of cell densities of the dinoflagellate Alexandrium catenella in relation to cell densities of diatoms. Hydrographic profiles of temperature, salinity, and nutrients (silicate and nitrate) were also made at each station. Data were analyzed to determine if there was any statistically significant evidence of allelopathic interference imparted by diatoms that impede A. catenella. A. catenella cells were most abundant in June, reaching 6,195 cells per …


Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso Aug 2020

Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso

University of New Orleans Theses and Dissertations

One of the most important gene families to play a role in adaptive immunity is the major histocompatibility complex (MHC). MHC class II loci are considered to be the most variable loci in the vertebrate genome, and studies have shown that this variability can be maintained through complex co-evolutionary dynamics between host and parasite. Despite the rich body of research into the MHC, there is comparatively little understanding of its genomic architecture in reptiles. Similarly, loci associated with innate immunity have received little attention in reptiles compared to other vertebrates. In the first chapter, we investigated the structure and organization …


Hind Wing Eyespots Of Brassolini Butterflies (Lepidoptera, Nymphalidae): Evolutionary Diversification And Functions In Anti-Predator Defense And Mating Behavior, Logan Crees Aug 2020

Hind Wing Eyespots Of Brassolini Butterflies (Lepidoptera, Nymphalidae): Evolutionary Diversification And Functions In Anti-Predator Defense And Mating Behavior, Logan Crees

University of New Orleans Theses and Dissertations

Ventral hind wing eyespots are prominent pattern elements in Brassolini butterflies, likely functioning in predator-prey interactions and reproductive activities. Caligo and Opsiphanes differ in male mate-seeking behaviors and it has been suggested that Caligo females use the male cua1 eyespot as a mate-locating cue, but Opsiphanes females do not seem to do so. We predict Caligo males should have larger eyespots than congeneric females, but the sexes would not differ in eyespot size in Opsiphanes. Our analyses supported both these predictions. Displacing the eyespot to the center of the wing makes eyespots more conspicuous, we asked if eyespot position …


Competitive Interactions: Spatial And Temporal Niche Partitioning Between Brook And Brown Trout In Southwest Michigan, Frederick J. Glassen Aug 2020

Competitive Interactions: Spatial And Temporal Niche Partitioning Between Brook And Brown Trout In Southwest Michigan, Frederick J. Glassen

Masters Theses

Niche diet partitioning between Brook Trout and Brown Trout were studied in two southwestern Michigan, USA streams, one dominated by Brook Trout, the other with both Brook and Brown Trout. Brook Trout are endemic to eastern North America and have been introduced throughout the world for sport fishing. Brown Trout were first introduced to Michigan in 1883 using a genetic strain from Germany. Stomach contents were collected from a population of Brook Trout in the absence of Brown Trout in Frost Creek, while the other population was in potential competition with Brown Trout in Cedar Creek. Absent Brown Trout, Brook …