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University of Colorado
1.
Flynn, Andrew James Haberstroh.
Morphological Predictors and Genetic Consequences of Nest Predation in the North American Barn Swallow Hirundo Rustica Erythrogaster.
Degree: MA, Ecology & Evolutionary Biology, 2012, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/23 
► Nest predation is the primary cause of reproductive failure in most bird species, and is a powerful source of natural selection. As nest predation…
(more)
▼ Nest predation is the primary cause of reproductive failure in most bird species, and is a powerful source of natural selection. As nest predation is strongly tied to an individual's reproductive performance, the ways in which parents respond to predation risk is likely shaped by natural selection. In particular, species that engage in multiple breeding attempts in a given season are able to modify their breeding strategies through extra-pair mating which might be influenced by predation events. I examined relationships between parental morphological variation, extra-pair mating, and nest predation in the North American barn swallow in order to examine morphological predictors and genetic consequences associated with nest predation in the wild. The findings of this study suggest that parental morphology may play a significant role in nest predation risk and that females may alter the paternity of her offspring after a predation event based on features of her mate's morphology.
Advisors/Committee Members: Rebecca J. Safran, Michael Breed, Samuel Flaxman.
Subjects/Keywords: Mating Strategies; Morphology; Nest Predation; Paternity; Ecology and Evolutionary Biology
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APA (6th Edition):
Flynn, A. J. H. (2012). Morphological Predictors and Genetic Consequences of Nest Predation in the North American Barn Swallow Hirundo Rustica Erythrogaster. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/23
Chicago Manual of Style (16th Edition):
Flynn, Andrew James Haberstroh. “Morphological Predictors and Genetic Consequences of Nest Predation in the North American Barn Swallow Hirundo Rustica Erythrogaster.” 2012. Masters Thesis, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/23.
MLA Handbook (7th Edition):
Flynn, Andrew James Haberstroh. “Morphological Predictors and Genetic Consequences of Nest Predation in the North American Barn Swallow Hirundo Rustica Erythrogaster.” 2012. Web. 24 Jan 2021.
Vancouver:
Flynn AJH. Morphological Predictors and Genetic Consequences of Nest Predation in the North American Barn Swallow Hirundo Rustica Erythrogaster. [Internet] [Masters thesis]. University of Colorado; 2012. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/23.
Council of Science Editors:
Flynn AJH. Morphological Predictors and Genetic Consequences of Nest Predation in the North American Barn Swallow Hirundo Rustica Erythrogaster. [Masters Thesis]. University of Colorado; 2012. Available from: https://scholar.colorado.edu/ebio_gradetds/23
University of Colorado
2.
Perkins, Jerome Philippe.
Influence of Food Web Structure on Predator-Prey Dynamics in a Patchy Environment.
Degree: MS, Applied Mathematics, 2013, University of Colorado
URL: https://scholar.colorado.edu/appm_gradetds/32
► In order to model the spatial distributions of predators and prey many investigators have used a simplified three-species system where a predator species consumes…
(more)
▼ In order to model the spatial distributions of predators and prey many investigators have used a simplified three-species system where a predator species consumes a prey species that consumes a resource. One of the recurring predictions from such models is that the spatial distribution of the predator will match the spatial distribution of the resource instead of that of the prey; this is known as ``leapfrogging". While it is interesting that leapfrogging is consistently predicted by models of three species, tritrophic systems, real biological communities are more complicated, being less like chains and more like multi-dimensional food webs (i.e., multiple prey and predator species interacting with each other). I ask: Are systems with more species and more connections among them well approximated by simpler, three-species single-chain models? I construct two different five-dimensional systems (a resource consumed by two prey species consumed by two predator species) and compare them to the single-chain system to see if more complicated systems yield the same predictions as a simpler single-chain system. I discovered that, in aggregate, the dynamics of predators in a multi-species web, is very similar to the dynamics of a simpler, single-chain system; yet individualy the dynamics of predator species in a multi-species web are very different from the dynamics of a simpler, single-chain system.
Advisors/Committee Members: Samuel Flaxman, Anne Dougherty, Juan Restrepo.
Subjects/Keywords: Dynamics; Predator; Prey; Spatial Distributions; Biology; Demography, Population, and Ecology
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APA (6th Edition):
Perkins, J. P. (2013). Influence of Food Web Structure on Predator-Prey Dynamics in a Patchy Environment. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/appm_gradetds/32
Chicago Manual of Style (16th Edition):
Perkins, Jerome Philippe. “Influence of Food Web Structure on Predator-Prey Dynamics in a Patchy Environment.” 2013. Masters Thesis, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/appm_gradetds/32.
MLA Handbook (7th Edition):
Perkins, Jerome Philippe. “Influence of Food Web Structure on Predator-Prey Dynamics in a Patchy Environment.” 2013. Web. 24 Jan 2021.
Vancouver:
Perkins JP. Influence of Food Web Structure on Predator-Prey Dynamics in a Patchy Environment. [Internet] [Masters thesis]. University of Colorado; 2013. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/appm_gradetds/32.
Council of Science Editors:
Perkins JP. Influence of Food Web Structure on Predator-Prey Dynamics in a Patchy Environment. [Masters Thesis]. University of Colorado; 2013. Available from: https://scholar.colorado.edu/appm_gradetds/32
University of Colorado
3.
Rodriguez, Michael John.
The Effects of Wind on Foraging Strategies of Atta cephalotes Leaf-Cutter Ants.
Degree: MS, Ecology & Evolutionary Biology, 2014, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/55
► Successful foragers alter their behavior in response to variation in local conditions, resulting in reduction of foraging costs and maximization of resource gain. In…
(more)
▼ Successful foragers alter their behavior in response to variation in local conditions, resulting in reduction of foraging costs and maximization of resource gain. In eusocial colonies, individuals may adjust their own efforts to maximize the productivity of the colony as a whole. Maximization of colony productivity can be achieved through sub-maximal individual performance. Attine leaf-cutter ant foragers often cut leaf fragments shorter than the hind legs could allow, suggesting other factors contribute to load size determination. Several studies have shown reasons why leaf-cutter ants cut smaller loads than they could maximally carry. The effects of wind speed on leaf-cutter load size selection were examined in this study and showed conditions in which leaf-cutter foragers change their behavior to cut larger loads than normal. In response to wind treatments, foragers cut larger leaf loads and fewer minima workers hitchhiked on those leaves. This study highlights behavioral plasticity of leaf-cutter foragers in response to local conditions on the foraging trail, and it adds to our knowledge of resource allocation in central-place foraging systems.
Advisors/Committee Members: Michael D. Breed, Rebecca Safran, Samuel Flaxman.
Subjects/Keywords: ants; behavior; efficiency; foraging; leaf-cutter; load selection; Behavior and Ethology
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APA (6th Edition):
Rodriguez, M. J. (2014). The Effects of Wind on Foraging Strategies of Atta cephalotes Leaf-Cutter Ants. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/55
Chicago Manual of Style (16th Edition):
Rodriguez, Michael John. “The Effects of Wind on Foraging Strategies of Atta cephalotes Leaf-Cutter Ants.” 2014. Masters Thesis, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/55.
MLA Handbook (7th Edition):
Rodriguez, Michael John. “The Effects of Wind on Foraging Strategies of Atta cephalotes Leaf-Cutter Ants.” 2014. Web. 24 Jan 2021.
Vancouver:
Rodriguez MJ. The Effects of Wind on Foraging Strategies of Atta cephalotes Leaf-Cutter Ants. [Internet] [Masters thesis]. University of Colorado; 2014. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/55.
Council of Science Editors:
Rodriguez MJ. The Effects of Wind on Foraging Strategies of Atta cephalotes Leaf-Cutter Ants. [Masters Thesis]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/ebio_gradetds/55
University of Colorado
4.
McCreery, Helen Felicity.
Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving.
Degree: PhD, 2018, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/123
► Across scales, complexity emerges within groups of simple individuals. In many cases, groups succeed at tasks that are well beyond the capabilities of individuals; this…
(more)
▼ Across scales, complexity emerges within groups of simple individuals. In many cases, groups succeed at tasks that are well beyond the capabilities of individuals; this is collective intelligence. Ants provide some of the best examples of collective intelligence, and groups of ants succeed at remarkable challenges. A highly conspicuous example of such behavior in ants is <i>cooperative transport</i>, which occurs when a group collectively moves a large, heavy food object. Cooperative transport groups must overcome two major challenges: 1) agreeing on a travel direction and 2) navigating around obstacles. The first challenge requires breaking deadlocks to reach a consensus decision. The second requires problem solving – groups must make a series of new decisions, each building on the previous. My goal was to discover the individual- and group-level mechanisms that allow some ant species to overcome these challenges, and spectacularly succeed at cooperative transport. At the individual level, I found that theoretically, even groups of individuals with simple behavioral rules can break deadlocks. Individuals only need to determine whether they are aligned with the majority. My theoretical work also indicates that individual persistence – reluctance to change direction – promotes group consensus. I tested this hypothesis empirically, and found that species with more persistent individuals form more coordinated groups, and artificially increasing persistence increases coordination. At the group level, I discovered that object size and mass affect group coordination time and speed, but not the maintenance of coordination. Finally, in a species of expert transporters, groups excel at maintaining consensus while navigating obstacles, and they add complexity to their navigation strategy only if simpler behavior fails. My dissertation contributes to our understanding of emergent group behavior by demonstrating simple behavioral rules and a trait – persistence – that promote consensus. I have identified object properties that influence transport in surprising ways, and found that groups use a flexible and robust problem solving strategy for obstacle navigation. This work elucidates important mechanisms that allow some species to excel at cooperative transport.
Advisors/Committee Members: Michael D. Breed, Samuel Flaxman, Rebecca Safran, Alexander Cruz, Nikolaus Correll.
Subjects/Keywords: collective behavior; collective decision; cooperative transport; decentralized control; emergent behavior; formicidae; Ecology and Evolutionary Biology; Entomology
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APA (6th Edition):
McCreery, H. F. (2018). Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/123
Chicago Manual of Style (16th Edition):
McCreery, Helen Felicity. “Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving.” 2018. Doctoral Dissertation, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/123.
MLA Handbook (7th Edition):
McCreery, Helen Felicity. “Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving.” 2018. Web. 24 Jan 2021.
Vancouver:
McCreery HF. Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving. [Internet] [Doctoral dissertation]. University of Colorado; 2018. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/123.
Council of Science Editors:
McCreery HF. Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving. [Doctoral Dissertation]. University of Colorado; 2018. Available from: https://scholar.colorado.edu/ebio_gradetds/123
University of Colorado
5.
Orlofske, Sarah Anne.
Predation on parasites and its consequences for transmission.
Degree: PhD, Ecology & Evolutionary Biology, 2013, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/43
► Predation and parasitism are each important ecological processes within communities and ecosystems. However, the interactions between predation and parasitism may have significant consequences for…
(more)
▼ Predation and parasitism are each important ecological processes within communities and ecosystems. However, the interactions between predation and parasitism may have significant consequences for transmission dynamics and disease in host populations. Predators play multiple roles including changing host densities, behavior, and morphology that could lead to different disease outcomes. Furthermore, direct predation on parasites can potentially lead to reduction in disease risk to host populations. Here, I used a combination of mathematical modeling, small-scale laboratory studies, and a semi-realistic mesocosm experiment to characterize parasite transmission dynamics, provide a predictive framework for the role of direct predation on parasites, and evaluate the direct and indirect (trait-mediated interactions) effects of multiple predators on transmission and infection. My study system included the trematode parasite,
Ribeiroia ondatrae, larval amphibian hosts, and a suite of invertebrate and vertebrate species that co-occur in nature. Using laboratory experiments and maximum likelihood approach, I characterized non-linear functions as the most accurate representation of transmission. These models capture the saturation of infection at high exposure levels and subsequent experiments with anesthetized hosts suggest that parasite behavior may be an underlying mechanism for nonlinear relationships. Next, I identified damselfly larvae and juvenile mosquitofish (
Gambusia affinis) as predators of
R. ondatrae and California Newts (
Taricha torosa) as alternative hosts. In transmission trials, both damselflies and newts reduced transmission by ~50% through the independent mechanisms of consumption and infection. Additional experiments including a wider range of parasite species showed that predation on parasites is based on predator foraging mode (active vs. ambush) and body size, parasite size and light availability. In more realistic aquatic communities with multiple trophic levels, I found that the trait-mediated indirect effects of predators of parasites and predators of hosts, including reduced activity and morphological changes were associated with higher infection compared to communities with predators absent. My research demonstrates both the direct and trait-mediated roles of predation on disease dynamics and identifies direct predation on parasites as an important factor in transmission dynamics. Future research should evaluate patterns of predator diversity and abundance with the prevalence and pathology due to
R. ondatrae in nature.
Advisors/Committee Members: Pieter Johnson, Samuel Flaxman, Brett Melbourne, Valerie McKenzie, David Bortz.
Subjects/Keywords: amphibians; community ecology; infectious diseases; predation; transmission; trematodes; Ecology and Evolutionary Biology; Parasitology; Population Biology
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APA (6th Edition):
Orlofske, S. A. (2013). Predation on parasites and its consequences for transmission. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/43
Chicago Manual of Style (16th Edition):
Orlofske, Sarah Anne. “Predation on parasites and its consequences for transmission.” 2013. Doctoral Dissertation, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/43.
MLA Handbook (7th Edition):
Orlofske, Sarah Anne. “Predation on parasites and its consequences for transmission.” 2013. Web. 24 Jan 2021.
Vancouver:
Orlofske SA. Predation on parasites and its consequences for transmission. [Internet] [Doctoral dissertation]. University of Colorado; 2013. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/43.
Council of Science Editors:
Orlofske SA. Predation on parasites and its consequences for transmission. [Doctoral Dissertation]. University of Colorado; 2013. Available from: https://scholar.colorado.edu/ebio_gradetds/43
University of Colorado
6.
McCreery, Helen Felicity.
Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving.
Degree: PhD, 2017, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/93
► Across scales, complexity emerges within groups of simple individuals. In many cases, groups succeed at tasks that are well beyond the capabilities of individuals;…
(more)
▼ Across scales, complexity emerges within groups of simple individuals. In many cases, groups succeed at tasks that are well beyond the capabilities of individuals; this is collective intelligence. Ants provide some of the best examples of collective intelligence, and groups of ants succeed at remarkable challenges. A highly conspicuous example of such behavior in ants is cooperative transport, which occurs when a group collectively moves a large, heavy food object. Cooperative transport groups must overcome two major challenges: 1) agreeing on a travel direction and 2) navigating around obstacles. The first challenge requires breaking deadlocks to reach a consensus decision. The second requires problem solving – groups must make a series of new decisions, each building on the previous. My goal was to discover the individual- and group-level mechanisms that allow some ant species to overcome these challenges, and spectacularly succeed at cooperative transport. At the individual level, I found that theoretically, even groups of individuals with simple behavioral rules can break deadlocks. Individuals only need to determine whether they are aligned with the majority. My theoretical work also indicates that individual persistence – reluctance to change direction – promotes group consensus. I tested this hypothesis empirically, and found that species with more persistent individuals form more coordinated groups, and artificially increasing persistence increases coordination. At the group level, I discovered that object size and mass affect group coordination time and speed, but not the maintenance of coordination. Finally, in a species of expert transporters, groups excel at maintaining consensus while navigating obstacles, and they add complexity to their navigation strategy only if simpler behavior fails. My dissertation contributes to our understanding of emergent group behavior by demonstrating simple behavioral rules and a trait – persistence – that promote consensus. I have identified object properties that influence transport in surprising ways, and found that groups use a flexible and robust problem solving strategy for obstacle navigation. This work elucidates important mechanisms that allow some species to excel at cooperative transport.
Advisors/Committee Members: Michael D. Breed, Samuel Flaxman, Rebecca Safran, Alexander Cruz, Nikolaus Correll.
Subjects/Keywords: collective behavior; collective decision; cooperative transport; decentralized control; emergent behavior; Formicidae; Ecology and Evolutionary Biology; Entomology
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APA ·
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APA (6th Edition):
McCreery, H. F. (2017). Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/93
Chicago Manual of Style (16th Edition):
McCreery, Helen Felicity. “Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving.” 2017. Doctoral Dissertation, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/93.
MLA Handbook (7th Edition):
McCreery, Helen Felicity. “Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving.” 2017. Web. 24 Jan 2021.
Vancouver:
McCreery HF. Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/93.
Council of Science Editors:
McCreery HF. Cooperative Transport in Ants: Emergent Coordination and Collective Problem Solving. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/ebio_gradetds/93
University of Colorado
7.
Knight, Kevin Bracy.
Global Primate Species Decline in the Anthropocene: Threats and Triage.
Degree: PhD, 2017, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/105
► The Anthropocene mass extinction, or sixth mass extinction, represents a threat to global biodiversity. The only precedents for extinction at this pace are events similar…
(more)
▼ The Anthropocene mass extinction, or sixth mass extinction, represents a threat to global biodiversity. The only precedents for extinction at this pace are events similar to the K-Pg extinction of the non-avian dinosaurs and over 75% of the other species on Earth at the time. To be effective, conservation science needs to rapidly change focus to a larger scale. In this dissertation, I explore several conservation avenues through the lenses of ecology and economics using global primate species to examine my hypotheses. In Chapter II, I assess shared traits among primates that may indicate increased extinction risk using a hierarchical Bayesian framework. I find the traits most associated with primate species’ risk are evolutionary relationship (i.e., closely related species are similarly endangered) and habitat specialization. In Chapter III, I combine species’ geographic ranges with historic human population maps dating back 200 years to assess whether primate species exhibit a lag in extinction after anthropogenic encroachment. I see strong evidence of extinction debt among primates; current species decline best correlates with human population density roughly 100 years in the past. In Chapter IV, I examine the role of national-scale socioeconomic factors in species risk. To do so, I test socioeconomic data for nations of the world as predictors of species risk within each nation. Analysis of socioeconomic factors show a tradeoff between the well-being of the people of a nation and primate risk. The higher the human standard of living, the greater the primate extinction risk. However, this analysis also illuminates the strength of international cooperation – species found in more countries are at less risk. In Chapter V, I explore conservation triage, a method of prioritizing which species to conserve, given limited resources. To do this, I modeled primate species extinctions across 150 years into the future under varying prioritization schemes and calculated extinction and phylogenetic diversity loss. I find triage focused on evolutionarily distinct species that are also at-risk may save more species and diversity than a method focused solely on the rarest species. The research in this dissertation supports addressing global primate extinction on a large scale – prioritizing the use of limited resources to address multiple species simultaneously.
Advisors/Committee Members: Christy M. McCain, Herbert Covert, Stacey Smith, Samuel Flaxman, Sharon Collinge.
Subjects/Keywords: conservation triage; ecology; economics; extinction; primate; conservation biology; Ecology and Evolutionary Biology; Other Ecology and Evolutionary Biology
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APA (6th Edition):
Knight, K. B. (2017). Global Primate Species Decline in the Anthropocene: Threats and Triage. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/105
Chicago Manual of Style (16th Edition):
Knight, Kevin Bracy. “Global Primate Species Decline in the Anthropocene: Threats and Triage.” 2017. Doctoral Dissertation, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/105.
MLA Handbook (7th Edition):
Knight, Kevin Bracy. “Global Primate Species Decline in the Anthropocene: Threats and Triage.” 2017. Web. 24 Jan 2021.
Vancouver:
Knight KB. Global Primate Species Decline in the Anthropocene: Threats and Triage. [Internet] [Doctoral dissertation]. University of Colorado; 2017. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/105.
Council of Science Editors:
Knight KB. Global Primate Species Decline in the Anthropocene: Threats and Triage. [Doctoral Dissertation]. University of Colorado; 2017. Available from: https://scholar.colorado.edu/ebio_gradetds/105
University of Colorado
8.
Mihaljevic, Joseph Richard.
Understanding the Effects of Host and Pathogen Diversity on Disease and Pathogen Transmission at Multiple Spatial Scales.
Degree: PhD, Ecology & Evolutionary Biology, 2014, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/60
► In wildlife communities, the diversity of both host species and pathogens can affect disease and transmission dynamics. However, the various mechanisms leading to these…
(more)
▼ In wildlife communities, the diversity of both host species and pathogens can affect disease and transmission dynamics. However, the various mechanisms leading to these biodiversity effects occur at strikingly different spatial scales. For my dissertation, I used empirical and theoretical tools to understand how pathogen and host diversity affect transmission at multiple scales. First, I conducted a series of laboratory experiments using a genus of viruses,
Ranavirus, which can cause devastating die-offs in amphibian populations. I asked how multiple virus types might interact to affect individual-level probabilities of infection and, subsequently, population-level transmission dynamics. I found that co-exposure to two
Ranavirus species substantially increased the probability of an amphibian larva becoming infected, as well as the average viral load among individuals. Concordantly, the presence of multiple
Ranavirus species led to larger epidemics in experimental populations, as well as an increased probability of mortality. This research illustrates that
Ranavirus coinfection could strongly mediate epidemic dynamics in natural amphibian populations. In the next part of my dissertation, I created an epidemiological model in which a single pathogen circulates through a vertebrate host community. I found that the relationship between host species richness and pathogen transmission could be positive, negative, or non-monotonic depending on how the host's total community density scales with host richness and the type of pathogen transmission assumed. These results highlight that host community composition influences transmission in complex ways, suggesting that observing a consistent effect of host diversity in natural systems is unlikely. Finally, scaling up and using a metacommunity framework, I developed a statistical method to explore how symbiont (including pathogen) communities are structured across space. I then applied this method to a large scale, longitudinal data set of amphibian symbiont communities and discovered that the structure of these communities changes through time and is predominantly influenced by temporal changes in host community composition. Overall, my research illustrates that transmission dynamics are influenced by factors at multiple spatial scales and that integrating across scales is important for understanding how, where, and when biodiversity will affect disease dynamics.
Advisors/Committee Members: Pieter T.J. Johnson, Andrew Martin, Samuel Flaxman, Christy McCain, Robert Garcea.
Subjects/Keywords: Bayesian inference; community ecology; disease ecology; epidemiology; metacommunity; Biodiversity; Biology; Epidemiology; Population Biology
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APA (6th Edition):
Mihaljevic, J. R. (2014). Understanding the Effects of Host and Pathogen Diversity on Disease and Pathogen Transmission at Multiple Spatial Scales. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/60
Chicago Manual of Style (16th Edition):
Mihaljevic, Joseph Richard. “Understanding the Effects of Host and Pathogen Diversity on Disease and Pathogen Transmission at Multiple Spatial Scales.” 2014. Doctoral Dissertation, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/60.
MLA Handbook (7th Edition):
Mihaljevic, Joseph Richard. “Understanding the Effects of Host and Pathogen Diversity on Disease and Pathogen Transmission at Multiple Spatial Scales.” 2014. Web. 24 Jan 2021.
Vancouver:
Mihaljevic JR. Understanding the Effects of Host and Pathogen Diversity on Disease and Pathogen Transmission at Multiple Spatial Scales. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/60.
Council of Science Editors:
Mihaljevic JR. Understanding the Effects of Host and Pathogen Diversity on Disease and Pathogen Transmission at Multiple Spatial Scales. [Doctoral Dissertation]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/ebio_gradetds/60
University of Colorado
9.
Joseph, Maxwell B.
Tools for the Occurrence of Free-Living and Symbiotic Organisms in Space and Time.
Degree: PhD, Ecology & Evolutionary Biology, 2016, University of Colorado
URL: https://scholar.colorado.edu/ebio_gradetds/79
► This doctoral dissertation broadly aims to improve methods for understanding the occurrence of organisms in space and time, including organisms that cause disease. The…
(more)
▼ This doctoral dissertation broadly aims to improve methods for understanding the occurrence of organisms in space and time, including organisms that cause disease. The processes that drive occurrence are often represented mathematically as ecological theories, which can be applied to uncover actionable insights into disease management. This was a focus of my first chapter which characterized the gap between disease ecology theory and infectious disease management. My second chapter focused on filling in a gap theoretically at the intersection of multi-host pathogens and host community disassembly. Specifically, I construct a theoretical model to evaluate disease consequences when hosts are extirpated according to a variety of rules predicted from community ecology. The third chapter develops a method to link representations of latent processes that drive species occurrence to observable (with error) data, with the goal of understanding multiple causal pathways in an occupancy model. The fourth also extends occupancy models, but to allow for multi-host multi-symbiont (parasites included) systems. Chapter five is somewhat different topically, focusing on missing species trait interpolation, but methodologically is not much of a departure, drawing on Bayesian hierarchical modeling as in the previous two chapters. The final chapter develops a theoretical model to generate predictions about the effect of host diversity on the diversity and transmission of symbiotic organisms.
Advisors/Committee Members: Pieter T. J. Johnson, Vanja Dukic, Samuel Flaxman, Andrew Martin, Valerie McKenzie.
Subjects/Keywords: wildlife; hosts and symbbiont; Ecology and Evolutionary Biology
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APA (6th Edition):
Joseph, M. B. (2016). Tools for the Occurrence of Free-Living and Symbiotic Organisms in Space and Time. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/ebio_gradetds/79
Chicago Manual of Style (16th Edition):
Joseph, Maxwell B. “Tools for the Occurrence of Free-Living and Symbiotic Organisms in Space and Time.” 2016. Doctoral Dissertation, University of Colorado. Accessed January 24, 2021.
https://scholar.colorado.edu/ebio_gradetds/79.
MLA Handbook (7th Edition):
Joseph, Maxwell B. “Tools for the Occurrence of Free-Living and Symbiotic Organisms in Space and Time.” 2016. Web. 24 Jan 2021.
Vancouver:
Joseph MB. Tools for the Occurrence of Free-Living and Symbiotic Organisms in Space and Time. [Internet] [Doctoral dissertation]. University of Colorado; 2016. [cited 2021 Jan 24].
Available from: https://scholar.colorado.edu/ebio_gradetds/79.
Council of Science Editors:
Joseph MB. Tools for the Occurrence of Free-Living and Symbiotic Organisms in Space and Time. [Doctoral Dissertation]. University of Colorado; 2016. Available from: https://scholar.colorado.edu/ebio_gradetds/79
. 
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