• Login
    View Item 
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Interactions Among Multiple Plastic Traits in Caterpillar Thermoregulation

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    azu_etd_15038_sip1_m.pdf
    Size:
    1.624Mb
    Format:
    PDF
    Download
    Author
    Nielsen, Matthew Erik
    Issue Date
    2016
    Keywords
    Behavior
    Caterpillar
    Color
    Phenotypic Plasticity
    Temperature
    Ecology & Evolutionary Biology
    Battus Philenor
    Advisor
    Papaj, Daniel R.
    
    Metadata
    Show full item record
    Publisher
    The University of Arizona.
    Rights
    Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
    Abstract
    Adaptive phenotypic plasticity is a key mechanism by which organisms deal with variation in many different aspects of their environment. Adaptive plasticity can occur in any trait, from aspects of biochemistry and morphology to behaviors. Because so many different traits can be plastic, organisms often respond plastically to a given change in their environment, such as an increase in temperature, with adaptive changes in multiple traits. Nevertheless, how these different plastic responses interact with each other and evolve together has received little attention. My research addresses these potential interactions among plastic traits and proposes new hypotheses regarding the causes and consequences of these interactions. It does so by focusing on heat avoidance in the caterpillars of Battus philenor (the pipevine swallowtail) which involves two distinct plastic mechanisms. First, the caterpillars can change color when they molt, a form of morphological plasticity in which they develop a red color under high temperatures which cools them by absorbing less solar radiation. Second, when the caterpillars become too hot, they will leave their host to seek cooler thermal refuges, a case of behavior as a form of plasticity. In terms of function, I demonstrated through field research that these two responses to high temperatures are largely redundant. Behavior provides a much stronger and faster response than color change, and red coloration provides little additional cooling when on a refuge. Instead, the primary benefit of color change is that it reduces the use of refuge seeking behavior, allowing the caterpillars to stay on their hosts longer. Using laboratory experiments, I demonstrated that this change in the use of refuge-seeking behavior with color occurs because color changes the cue for the behavior, body temperature, rather having any effect on how the caterpillar responds to that cue. Alternatively, similar experiments on caterpillars of varying sizes show that developmental size change lowers the body temperature at which caterpillars leave their host, demonstrating a change in the response to the cue (although larger caterpillars are also warmer, so both mechanisms are likely relevant for how size changes the expression of behavior). All of my research to this point was conducted on the local population in southern Arizona, which experiences quite high temperatures, but B. philenor is also found in much cooler environments, such as the Appalachian Mountains. Given this variation in their thermal environment, I used common garden experiments to compare the capacity for color change and refuge-seeking among B. philenor caterpillars from across the species range. Both color change and refuge seeking not only occurred in all populations, but also had the same reaction norms, occurring at the same temperatures and to the same degree. This is particularly notable for color change, which is not observed in the wild in northeastern populations, and thus has persisted despite minimal if any use. Overall, I have shown that studies of plasticity need to account for plasticity in different traits as well as the interactions between these forms of plasticity. My research on B. philenor provides a model for how to address these interactions, which future research can extend to additional organisms and environmental circumstances.
    Type
    text
    Electronic Dissertation
    Degree Name
    Ph.D.
    Degree Level
    doctoral
    Degree Program
    Graduate College
    Ecology & Evolutionary Biology
    Degree Grantor
    University of Arizona
    Collections
    Dissertations

    entitlement

     
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.