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- Creators: Barrett, The Honors College
- Status: Published
Description
Foraging has complex effects on whole-organism homeostasis, and there is considerable evidence that foraging behavior is influenced by both environmental factors (e.g., food availability, predation risk) and the physiological condition of an organism. The optimization of foraging behavior to balance costs and benefits is termed state-dependent foraging (SDF) while behavior that seeks to protect assets of fitness is termed the asset protection principle (APP). A majority of studies examining SDF have focused on the role that energy balance has on the foraging of organisms with high metabolism and high energy demands ("high-energy systems" such as endotherms). In contrast, limited work has examined whether species with low energy use ("low-energy systems" such as vertebrate ectotherms) use an SDF strategy. Additionally, there is a paucity of evidence demonstrating how physiological and environmental factors other than energy balance influence foraging behavior (e.g. hydration state and free-standing water availability). Given these gaps in our understanding of SDF behavior and the APP, I examined the state-dependency and consequences of foraging in a low-energy system occupying a resource-limited environment - the Gila monster (Heloderma suspectum, Cope 1869). In contrast to what has been observed in a wide variety of taxa, I found that Gila monsters do not use a SDF strategy to manage their energy reserves and that Gila monsters do not defend their energetic assets. However, hydration state and free-standing water availability do affect foraging behavior of Gila monsters. Additionally, as Gila monsters become increasingly dehydrated, they reduce activity to defend hydration state. The SDF behavior of Gila monsters appears to be largely driven by the fact that Gila monsters must separately satisfy energy and water demands with food and free-standing water, respectively, in conjunction with the timescale within which Gila monsters balance their energy and water budgets (supra-annually versus annually, respectively). Given these findings, the impact of anticipated changes in temperature and rainfall patterns in the Sonoran Desert are most likely going to pose their greatest risks to Gila monsters through the direct and indirect effects on water balance.
ContributorsWright, Christian (Author) / Denardo, Dale F. (Thesis advisor) / Harrison, Jon (Committee member) / McGraw, Kevin (Committee member) / Sullivan, Brian (Committee member) / Wolf, Blair (Committee member) / Arizona State University (Publisher)
Created2014
Description
Parental care provides many benefits to offspring. One widely realized benefit is enhanced regulation of offspring's thermal environment. The developmental thermal environment during development can be optimized behaviorally through nest site selection and brooding, and it can be further enhanced by physiological heat production. In fact, enhancement of the developmental thermal environment has been proposed as the initial driving force for the evolution of endothermy in bird and mammals. I used pythons (Squamata: Pythonidae) to expand existing knowledge of behavioral and physiological parental tactics used to regulate offspring thermal environment. I first demonstrated that brooding behavior in the Children's python (Antaresia childreni) is largely driven by internal mechanisms, similar to solitary birds, suggesting that the early evolution of the parent-offspring association was probably hormonally driven. Two species of python are known to be facultatively thermogenic (i.e., are endothermic during reproduction). I expand current knowledge of thermogenesis in Burmese pythons (Python molurus) by demonstrating that females use their own body temperature to modulate thermogenesis. Although pythons are commonly cited as thermogenic, the actual extent of thermogenesis within the family Pythonidae is unknown. Thus, I assessed the thermogenic capability of five previously unstudied species of python to aid in understanding phylogenetic, morphological, and distributional influences on thermogenesis in pythons. Results suggest that facultative thermogenesis is likely rare among pythons. To understand why it is rare, I used an artificial model to demonstrate that energetic costs to the female likely outweigh thermal benefits to the clutch in species that do not inhabit cooler latitudes or lack large energy reserves. In combination with other studies, these results show that facultative thermogenesis during brooding in pythons likely requires particular ecological and physiological factors for its evolution.
ContributorsBrashears, Jake (Author) / DeNardo, Dale (Thesis advisor) / Harrison, Jon (Committee member) / Deviche, Pierre (Committee member) / McGraw, Kevin (Committee member) / Smith, Andrew (Committee member) / Arizona State University (Publisher)
Created2012
Description
The Mexican gray wolf (Canis lupus baileyi) is a genetically distinct subspecies of the gray wolf (Canis lupus) that was driven to the brink of extinction as a result of human persecution. The wolf is listed as Endangered under the Endangered Species Act, and a recovery program is underway in Arizona and New Mexico to restore its population. However, the wolf is struggling to recover due to high mortality, which is a result of continued human hostility toward it. This thesis examines historical and current human attitudes toward the wolf and the implications that they have had on the extermination and recovery of the subspecies. An overview is given of wolf biology, the history of wolf extermination and recovery, and recent events relating to the recovery of the wolf. Negative impacts on ranching, hunting, and human safety are the main reasons for opposition toward wolves and wolf recovery; these concerns are analyzed, and solutions to them are proposed, with the goal of addressing them while fostering non-lethal coexistence with the wolf. In addition, opposition to wolves and wolf recovery is tied in with larger socio-political issues and is influenced by the representation of the wolf in culture; these issues in the context of wolves are also analyzed.
ContributorsLenk, Heather Nicole (Author) / Smith, Andrew (Thesis director) / Minteer, Ben (Committee member) / Brown, David E. (Committee member) / School of Life Sciences (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
A literature review summarizing the current status of conservation efforts of the Mojave Desert tortoise (Gopherus agassizii) including a brief overview of the Endangered Species Act (ESA) and its applicability to this species' conservation. A genetic and physiological comparison of the morphologically similar Mojave species with the Sonoran (Gopherus morafkai) species proceeded by an analysis of if and how the ESA should apply to the Sonoran population. Analysis of current plans and interagency cooperations followed by a multi-step proposal on how best to conserve the Sonoran population of Desert tortoise.
ContributorsKulik, Elise Chikako (Author) / Kusumi, Kenro (Thesis director) / Tollis, Marc (Committee member) / Wilson Sayres, Melissa (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
White-nose syndrome (WNS) is a fungal infection devastating bat populations throughout eastern North America. WNS is caused by a fungus, Pseudogymnoascus destructans (Pd), that invades the skin of hibernating bats. While there are a number of treatments being researched, there is currently no effective treatment for WNS that is deployed in the field, except a few being tested on a limited scale. Bats have lowered immune function and response during hibernation, which may increase susceptibility to infection during the winter months. Antimicrobial peptides (AMPs) are a crucial component of the innate immune system and serve as barriers against infection. AMPs are constitutively expressed on skin and facilitate wound healing, stimulate other immune responses, and may also stay active on bat skin during hibernation. AMPs are expressed by all tissues, have direct killing abilities against microbes, and are a potential treatment for bats infected with Pd. In this investigation, the fungicidal activity of several readily available commercial AMPs were compared, and killing assay protocols previously investigated by Frasier and Lake were replicated to establish a control trial for use in future killing assays. Another aim of this investigation was to synthesize a bat-derived AMP for use in the killing assay. Sequences of bat-derived AMPs have been identified in bat skin samples obtained from a large geographic sampling of susceptible and resistant species. Contact was made with GenScript Inc., the company from which commercially available AMPs were purchased, to determine the characteristics of peptide sequences needed to synthesize an AMP for lab use. Based on recommendations from GenScript Inc., peptide sequences need to have a hydrophobicity of less than 50% and a sequence length of less than 50 amino acids. These criteria serve as a potential barrier because none of the known bat-derived sequences analyzed satisfy both of these requirements. The final aim of this study was to generate a conceptual model of the immune response molecules activated when bats are exposed to a fungal pathogen such as Pd. Overall, this work investigated sources of variability between trials of the killing assay, analyzed known bat-derived peptide sequences, and generated a conceptual model that will serve as a guideline for identification of immune response molecules on the skin of bats in future proteomics work.
ContributorsBarton, Madisen L (Author) / Moore, Marianne (Thesis director) / Penton, Christopher (Committee member) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The International Union for Conservation of Nature's Red List of Threatened Species is the most comprehensive and objective global approach to evaluate the conservation status of species by categorizing species based on relative extinction risk. For the Global Muranidae IUCN Red List assessment, all known, taxonomically valid species of Muraenidae were assessed for their extinction risk using the IUCN Red List Global Categories and Criteria. Of all 208 Muraenidae species, it was concluded that 86% of species qualified for Least Concern, 13% of species are Data Deficient, and 1% of species qualified for a threatened category. Channomuraena bauchotae is listed as threatened under VU D2 and Gymnothorax parini qualified for VU B2ab(iii). This study will have brought the International Union for the Conservation of Nature one step closer to their goal of conducting Red List assessments of all the world's species(not including microorganisms). Future implications of this study may include future monitoring of key habitat areas and species or conducting further research to gain a more in depth understanding of the life history and threats to Muraenidae.
ContributorsLaurence, Paige Marie (Author) / Polidoro, Beth (Thesis director) / Ralph, Gina (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
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
Description
This thesis examines how the wording of proposed government policies can affect the level of public support that a given policy generates. By surveying 158 Phoenix residents, I tested the differing degrees of support that voters would have for a proposed city ordinance, which would stop Homeowners' Associations from restricting the use of native desert plants in residential landscaping. The ordinance was framed in the survey as a self-governance issue or a water conservation issue. I found that the message frames had little effect on the overall level of support for the ordinance, since most residents had moderate support for the policy. However, participants who were either residents of Homeowners' Associations that did not have native plant restrictions, or native residents of Arizona, demonstrated greater levels of support for the self-determination frame of the proposed ordinance. These findings have implications for policy makers who use targeted messages to establish pro-environmental policies at the local level.
ContributorsSmith, Mary Hannah (Author) / Darnall, Nicole (Thesis director) / Ramirez, Mark (Committee member) / Tetreault, Colin (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Politics and Global Studies (Contributor)
Created2013-05
Description
Zoos are doing amazing projects to help wildlife globally and locally. A lot of people aren't aware of what goes on with these conservation projects because much of it happens behind the scenes. So I decided to make a film to explain how zoos facilitate our world's wildlife. My film can be viewed at this link: https://www.youtube.com/watch?v=_JmLGf138zY
ContributorsRossman, Chloe June (Author) / Sandler, Kevin (Thesis director) / Wells, Stuart (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Film, Dance and Theatre (Contributor)
Created2014-05
Description
The purpose of my thesis is to illustrate the story of the black-footed ferret's conservation, and to provide my own suggestions for how to eventually get the species removed from the Endangered Species List, marking a successful rebound in population numbers. I highlight my personal experience working at the Phoenix Zoo's black-footed ferret breeding center. In the first chapter, I present the species by describing its morphology, diet, reproduction, behaviors, range, and habitat. In the second chapter, I recount the chronological history of the conservation of the species, starting with its rediscovery following its putative "extinction", and ending with its present status. In the third chapter, I discuss the threats that have led to the species' overall decline and continue to affect its persistence today. In the fourth and final chapter, I conclude by making recommendations regarding what needs to occur in order to eventually get the species delisted.
ContributorsGeer, Emily Maren (Author) / Smith, Andrew T. (Thesis director) / Minteer, Ben (Committee member) / Wells, Stuart (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05