Between Dec 19, 2024 and Jan 2, 2025, datasets can be submitted to DRUM but will not be processed until after the break. Staff will not be available to answer email during this period, and will not be able to provide DOIs until after Jan 2. If you are in need of a DOI during this period, consider Dryad or OpenICPSR. Submission responses to the UDC may also be delayed during this time.
 

Behavioral ecology of parasitoid diet breadth and insect defenses

Loading...
Thumbnail Image

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

Behavioral ecology of parasitoid diet breadth and insect defenses

Published Date

2017-07

Publisher

Type

Thesis or Dissertation

Abstract

One of the primary challenges animals face is consuming enough nutrients of sufficient quality that they might realize their reproductive potential. Many strategies have evolved, but robust explanations for the causes and consequences of variation in diet breadth remain elusive. I’ve used field and comparative lab studies of a specialist parasitoid wasp (Pteromalus cassotis) with a closely-related generalist (Pteromalus puparum) across several potential butterfly host species to better understand how physiological and behavioral trade-offs might limit parasitoids' host ranges. When paired with eleven host species, both parasitoids preferred those hosts on which they performed best, but I found little support for the idea that physiological trade-offs drive the evolution of specialized foraging strategies. Intriguingly, the generalist was more likely than the specialist to accept unsuitable hosts, while the specialist was more likely than the generalist to reject suitable hosts. I also reared monarch butterflies (Danaus plexippus) to be more or less chemically defended and found that host toxicity influenced the behavior and performance of the specialist. The generalist often killed monarch hosts, but was incapable of developing in them. Finally, I investigated the role of behavior in avoiding natural enemy-induced mortality of insect pupae, which are relatively immobile and are often presumed to be vulnerable to natural enemies. I review many examples to show that pupae likely benefit from a variety of behaviors performed before pupation (by the larva or pre-pupa), behaviors of the pupa itself, and behaviors of conspecific and heterospecific individuals. Taken together, my dissertation provides the first details on the natural history and chemical ecology of interactions between P. cassotis and the monarch butterfly. My findings suggest that, in some cases, behavioral decisions may be more important than physiological trade-offs in shaping animal diet breadth. These findings have implications for organisms in rapidly changing environments and biological control efforts because they demonstrate that specialist foragers may retain the evolutionary potential for host switches, and generalists can cause difficult-to-measure non-target mortality.

Description

University of Minnesota Ph.D. dissertation.July 2017. Major: Ecology, Evolution and Behavior. Advisor: Karen Oberhauser. 1 computer file (PDF); xii, 153 pages.

Related to

Replaces

License

Collections

Series/Report Number

Funding information

Isbn identifier

Doi identifier

Previously Published Citation

Other identifiers

Suggested citation

Stenoien, Carl. (2017). Behavioral ecology of parasitoid diet breadth and insect defenses. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/206621.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.