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Over the past two decades there has been much discussion surrounding the potential of zoos as conservation institutions. Although zoos have clearly intensified their rhetorical and programmatic commitment to conservation (both ex situ and in situ), many critics remain skeptical of these efforts. This study was comprised of two parts:

Over the past two decades there has been much discussion surrounding the potential of zoos as conservation institutions. Although zoos have clearly intensified their rhetorical and programmatic commitment to conservation (both ex situ and in situ), many critics remain skeptical of these efforts. This study was comprised of two parts: 1) an investigation of the general relationship between U.S. zoological institutions and the conservation agenda, and 2) a more specific single case study of conservation engagement and institutional identity at the Phoenix Zoo. Methods included extensive literature review, expert interviews with scholars and zoo professionals, site visits to the Phoenix Zoo and archival research. I found that the Phoenix Zoo is in the process of consciously creating a conservation-centered institutional identity by implementing and publicizing various conservation initiatives. Despite criticism of the embrace of conservation by zoos today, these institutions will be increasingly important agents of biodiversity protection and conservation education in this century.
ContributorsLove, Karen (Author) / Minteer, Ben (Thesis advisor) / Kinzig, Ann (Committee member) / Collins, James (Committee member) / Arizona State University (Publisher)
Created2014
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Description
In complex consumer-resource type systems, where diverse individuals are interconnected and interdependent, one can often anticipate what has become known as the tragedy of the commons, i.e., a situation, when overly efficient consumers exhaust the common resource, causing collapse of the entire population. In this dissertation I use mathematical modeling

In complex consumer-resource type systems, where diverse individuals are interconnected and interdependent, one can often anticipate what has become known as the tragedy of the commons, i.e., a situation, when overly efficient consumers exhaust the common resource, causing collapse of the entire population. In this dissertation I use mathematical modeling to explore different variations on the consumer-resource type systems, identifying some possible transitional regimes that can precede the tragedy of the commons. I then reformulate it as a game of a multi-player prisoner's dilemma and study two possible approaches for preventing it, namely direct modification of players' payoffs through punishment/reward and modification of the environment in which the interactions occur. I also investigate the questions of whether the strategy of resource allocation for reproduction or competition would yield higher fitness in an evolving consumer-resource type system and demonstrate that the direction in which the system will evolve will depend not only on the state of the environment but largely on the initial composition of the population. I then apply the developed framework to modeling cancer as an evolving ecological system and draw conclusions about some alternative approaches to cancer treatment.
ContributorsKareva, Irina (Author) / Castillo-Chavez, Carlos (Thesis advisor) / Collins, James (Committee member) / Nagy, John (Committee member) / Smith, Hal (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Despite years of effort, the field of conservation biology still struggles to incorporate theories of animal behavior. I introduce in Chapter I the issues surrounding the disconnect between behavioral ecology and conservation biology, and propose the use of behavioral knowledge in population viability analysis. In Chapter II, I develop a

Despite years of effort, the field of conservation biology still struggles to incorporate theories of animal behavior. I introduce in Chapter I the issues surrounding the disconnect between behavioral ecology and conservation biology, and propose the use of behavioral knowledge in population viability analysis. In Chapter II, I develop a framework that uses three strategies for incorporating behavior into demographic models, outline the costs of each strategy through decision analysis, and build on previous work in behavioral ecology and demography. First, relevant behavioral mechanisms should be included in demographic models used for conservation decision-making. Second, I propose rapid behavioral assessment as a useful tool to approximate demographic rates through regression of demographic phenomena on observations of related behaviors. This technique provides behaviorally estimated parameters that may be applied to population viability analysis for use in management. Finally, behavioral indices can be used as warning signs of population decline. The proposed framework combines each strategy through decision analysis to provide quantitative rules that determine when incorporating aspects of conservation behavior may be beneficial to management. Chapter III applies this technique to estimate birthrate in a colony of California sea lions in the Gulf of California, Mexico. This study includes a cost analysis of the behavioral and traditional parameter estimation techniques. I then provide in Chapter IV practical recommendations for applying this framework to management programs along with general guidelines for the development of rapid behavioral assessment.
ContributorsWildermuth, Robert (Author) / Gerber, Leah R. (Thesis advisor) / Collins, James (Committee member) / Smith, Andrew (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Evolution is the foundation of biology, yet it remains controversial even among college biology students. Acceptance of evolution is important for students if we want them to incorporate evolution into their scientific thinking. However, students’ religious beliefs are a consistent barrier to their acceptance of evolution due to a perceived

Evolution is the foundation of biology, yet it remains controversial even among college biology students. Acceptance of evolution is important for students if we want them to incorporate evolution into their scientific thinking. However, students’ religious beliefs are a consistent barrier to their acceptance of evolution due to a perceived conflict between religion and evolution. Using pre-post instructional surveys of students in introductory college biology, Study 1 establishes instructional strategies that can be effective for reducing students' perceived conflict between religion and evolution. Through interviews and qualitative analyses, Study 2 documents how instructors teaching evolution at public universities may be resistant towards implementing strategies that can reduce students' perceived conflict, perhaps because of their own lack of religious beliefs and lack of training and awareness about students' conflict with evolution. Interviews with religious students in Study 3 reveals that religious college biology students can perceive their instructors as unfriendly towards religion which can negatively impact these students' perceived conflict between religion and evolution. Study 4 explores how instructors at Christian universities, who share the same Christian backgrounds as their students, do not struggle with implementing strategies that reduce students' perceived conflict between religion and evolution. Cumulatively, these studies reveal a need for a new instructional framework for evolution education that takes into account the religious cultural difference between instructors who are teaching evolution and students who are learning evolution. As such, a new instructional framework is then described, Religious Cultural Competence in Evolution Education (ReCCEE), that can help instructors teach evolution in a way that can reduce students' perceived conflict between religion and evolution, increase student acceptance of evolution, and create more inclusive college biology classrooms for religious students.
ContributorsBarnes, Maryann Elizabeth (Author) / Brownell, Sara (Thesis advisor) / Nesse, Randolph (Committee member) / Collins, James (Committee member) / Husman, Jenefer (Committee member) / Maienschein, Jane (Committee member) / Arizona State University (Publisher)
Created2018
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Description
Guided by Tinto’s Theory of College Student Departure, I conducted a set of five studies to identify factors that influence students’ social integration in college science active learning classes. These studies were conducted in large-enrollment college science courses and some were specifically conducted in undergraduate active learning biology courses.

Guided by Tinto’s Theory of College Student Departure, I conducted a set of five studies to identify factors that influence students’ social integration in college science active learning classes. These studies were conducted in large-enrollment college science courses and some were specifically conducted in undergraduate active learning biology courses. Using qualitative and quantitative methodologies, I identified how students’ identities, such as their gender and LGBTQIA identity, and students’ perceptions of their own intelligence influence their experience in active learning science classes and consequently their social integration in college. I also determined factors of active learning classrooms and instructor behaviors that can affect whether students experience positive or negative social integration in the context of active learning. I found that students’ hidden identities, such as the LGBTQIA identity, are more relevant in active learning classes where students work together and that the increased relevance of one’s identity can have a positive and negative impact on their social integration. I also found that students’ identities can predict their academic self-concept, or their perception of their intelligence as it compares to others’ intelligence in biology, which in turn predicts their participation in small group-discussion. While many students express a fear of negative evaluation, or dread being evaluated negatively by others when speaking out in active learning classes, I identified that how instructors structure group work can cause students to feel more or less integrated into the college science classroom. Lastly, I identified tools that instructors can use, such as name tents and humor, which can positive affect students’ social integration into the college science classroom. In sum, I highlight inequities in students’ experiences in active learning science classrooms and the mechanisms that underlie some of these inequities. I hope this work can be used to create more inclusive undergraduate active learning science courses.
ContributorsCooper, Katelyn M (Author) / Brownell, Sara E (Thesis advisor) / Stout, Valerie (Committee member) / Collins, James (Committee member) / Orchinik, Miles (Committee member) / Zheng, Yi (Committee member) / Arizona State University (Publisher)
Created2018
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Description
Recognizing that CEOs are less capable of diversifying their employment risks than shareholders who could diversify their investment risks through portfolio investments, agency theory assumes that CEOs tend to be risk averse compared with shareholders. Based on this assumption, agency theory scholars suggest that to align the risk preference of

Recognizing that CEOs are less capable of diversifying their employment risks than shareholders who could diversify their investment risks through portfolio investments, agency theory assumes that CEOs tend to be risk averse compared with shareholders. Based on this assumption, agency theory scholars suggest that to align the risk preference of CEOs with that of shareholders, CEOs need to be closely monitored and have less power. SEC regulators have been adopting the suggestion and accordingly CEO power has been reduced in the past decades. However, the empirical results are mixed and cannot provide solid support for the suggestion that reducing CEO power could lead the CEO to take more risks.

Considering that managerial risk taking is an important issue in strategic management research and agency theory has been widely adopted in academia and business worlds, it is imperative to clarify the mechanism behind the relationship between CEO power and risk taking. My study aims to fill this research gap. In this study I follow agency theory to take an employment security perspective and fully consider how CEOs’ concern about employment security is affected by their power and ownership structure to enrich the understanding of the effects of CEO power and ownership structure on risk taking. I fine-tune the key concept CEO power into the CEO power over board and introduce a key aspect of ownership structure - nontransient investor ownership. I further suggest that CEO power over board and nontransient investor ownership affect CEOs’ employment security and the resulting CEO risk taking. In addition, I consider a set of industry and firm characteristics as the boundary conditions for the effects of CEO power and nontransient investor ownership on CEO risk-taking. This set of industry and firm characteristics include industry complexity, industry dynamism, industry munificence and firm slack.

I test my theory using a large-scale, multi-year sample of U.S. publicly listed S&P 1500 firms between 2001 and 2017. My main hypotheses about the effects of CEO power over board and nontransient investor ownership on CEO risk taking receive strong support.
ContributorsZhu, Qi (Author) / Shen, Wei (Thesis advisor) / Zhu, David (Thesis advisor) / Certo, Trevis (Committee member) / Arizona State University (Publisher)
Created2019
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Description
One way pathogen prevalence is maintained is by persistence within reservoir host species. Reservoir hosts are species that do not show any signs of disease when a pathogen infects them. As a result, the pathogen survives and is able to remain in the host population. Batrachochytrium dendrobatidis (Bd) is a

One way pathogen prevalence is maintained is by persistence within reservoir host species. Reservoir hosts are species that do not show any signs of disease when a pathogen infects them. As a result, the pathogen survives and is able to remain in the host population. Batrachochytrium dendrobatidis (Bd) is a chytrid fungus that has caused extensive amphibian declines. It has been suspected that reservoir hosts are a key to Bd remaining in certain amphibian populations. I studied dragonfly naiads (Anisoptera spp.), the aquatic life cycle stage immediately following hatching and preceding the emergence of wings, as potential reservoir hosts for Bd on the Mogollon Rim in Arizona. On the Mogollon Rim winter temperatures fall below the optimal thermal range for Bd. Boreal chorus frogs (Pseudacris maculata), the most common amphibian species on the Rim, maintain subzero body temperatures to survive the winter. Since the optimal thermal range for Bd is between 4°C and 25°C, it is unlikely that Bd can grow on the skin of these frogs during winter. As a result, it is unknown how Bd prevalence is maintained in the area. Recent studies showed that Bd can grow in non-amphibian hosts. I hypothesized that Bd could grow within the digestive tracts of dragonfly naiads, since they stay in the water and don’t maintain subzero body temperatures during the cold winters on the Rim. Non-native and native naiads were both included in this study; the non-native naiads were purchased from a company in California while the native naiads were captured from ponds on the Mogollon Rim. The digestive tracts of the naiads were then dissected, and the DNA was extracted using an animal tissue spin-column protocol. The extracted DNA was analyzed by qPCR. The qPCR analysis of the native and non-native dragonfly naiads revealed that the samples were either Bd-negative or very weakly Bd-positive, with most being the former. Based on these results, it does not appear that naiads are biologically significant reservoir hosts for Bd.
ContributorsAnigwe, Christopher (Author) / Collins, James (Thesis director) / DeNardo, Dale (Committee member) / Brus, Evan (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Amphibians have been experiencing a worldwide decline that is in part caused by an infectious disease, chytridiomycosis, specific to frogs and salamanders. Globally many species have declined or gone extinct because of the pathogenic fungus Batrachochytrium dendrobatidis, also known as the amphibian chytrid or Bd. By the time Bd was

Amphibians have been experiencing a worldwide decline that is in part caused by an infectious disease, chytridiomycosis, specific to frogs and salamanders. Globally many species have declined or gone extinct because of the pathogenic fungus Batrachochytrium dendrobatidis, also known as the amphibian chytrid or Bd. By the time Bd was discovered it was too late to stop the spread and it has now been found on almost every continent. The trade of captive amphibians, used as pets, bait, and educational animals provides an opportunity to spread Bd. Because some amphibians can carry Bd without experiencing symptoms, it is possible for even healthy looking amphibians to spread the amphibian chytrid if they are moved from one location to another. Recently, a new species Batrachochytrium salamandrivorans (Bsal) was found on salamanders. Bsal was identified before it reached the United States, prompting concern regarding its spread and a call for regulation regarding the trade of captive amphibians. There are some regulations in place controlling the trade of amphibians, but they are insufficient to stop the spread of amphibian chytrid in captive populations. A 2016 law prohibits the importation of 201 salamander species. However, there is no central organization to sample or certify if amphibians are free from Bd or Bsal. Although some stores say they test for these pathogens the tests are unregulated and not reported to any central body. If the captive amphibian trade is to go disease free, there would need to be a significant push to coordinate testing efforts. To estimate Bd's prevalence in Arizona captive amphibian populations, I contacted pet stores, bait stores, and sanctuary or educational organizations to ask if I could sample their amphibian collections. My research built on the 2008 work of Angela Picco, who sampled for the amphibian chytrid in Arizona bait shops. I found that amphibian owners were often hesitant and unwilling to participate in this research opportunity. There are multiple reasons for this hesitancy including a fear of increased regulation, the potential for reporting to a government agency (USDA), or the eventual cessation of amphibian trade. The lack of willing participants suggests there may be difficulties in coordinating future sampling efforts for Bd and Bsal.
ContributorsFadlovich, Rachel Maurine (Author) / Collins, James (Thesis director) / Minteer, Ben (Committee member) / Brus, Evan (Committee member) / School of Life Sciences (Contributor) / Department of English (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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With the new independence of adulthood, college students are a group susceptible to adopting unsupported, if not harmful, health practices. A survey of Arizona State University undergraduate students (N=200) was conducted to evaluate supplement use, trust in information sources, and beliefs about supplement regulation. Of those who reported using supplements,

With the new independence of adulthood, college students are a group susceptible to adopting unsupported, if not harmful, health practices. A survey of Arizona State University undergraduate students (N=200) was conducted to evaluate supplement use, trust in information sources, and beliefs about supplement regulation. Of those who reported using supplements, college students most frequently received information from friends and family. STEM majors in fields unrelated to health who were taking a supplement were found to be less likely to receive information about the supplement from a medical practitioner than those in health fields or those in non-STEM majors (-26.9%, p=0.018). STEM majors in health-related fields were 15.0% more likely to treat colds and/or cold symptoms with research-supported methods identified from reliable sources, while non-health STEM and non-STEM majors were more likely to take unsupported cold treatments (p=0.010). Surveyed students, regardless of major, also stated they would trust a medical practitioner for supplement advice above other sources (88.0%), and the majority expressed a belief that dietary supplements are approved/regulated by the government (59.8%).
ContributorsPerez, Jacob Tanner (Author) / Hendrickson, Kirstin (Thesis director) / Lefler, Scott (Committee member) / College of Liberal Arts and Sciences (Contributor) / School of Molecular Sciences (Contributor) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Conservation is a complicated entity consisting of a multitude of professional fields including social issues, cultural issues, and physical science. This thesis evaluates the positive and negative aspects of two broad types of conservation: top down fortress conservation and bottom up community-based conservation. Fortress conservation has many negative aspects, such

Conservation is a complicated entity consisting of a multitude of professional fields including social issues, cultural issues, and physical science. This thesis evaluates the positive and negative aspects of two broad types of conservation: top down fortress conservation and bottom up community-based conservation. Fortress conservation has many negative aspects, such as displacing human communities and preventing utilization of resources. However, it also has positive aspects, such as preventing the destruction of delicate ecosystems and slowing down extinctions. Community-based conservation is more inclusive and focuses on including the indigenous populations located within the proposed conservation site in the decision-making process. Its negatives include having an anthropocentric goal instead of valuing nature's intrinsic values. Understanding the differences inherent in these two methods is necessary in order to implement a conservation network with the highest chance for success.
ContributorsFink, Laurel Berylline (Author) / Smith, Andrew (Thesis director) / Collins, James (Committee member) / Minteer, Ben (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05