Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


Calabrese Dissertation 11-30-21.pdf (1.46 MB)

ETD Abstract Container

Abstract Header

Theoretical and empirical tests of evolutionary models predicting androdioecy to be an evolutionarily stable mating system

Calabrese, Alissa
http://orcid.org/0000-0002-3295-236X
http://rave.ohiolink.edu/etdc/view?acc_num=akron1637261675658712

Abstract Details

2021, Doctor of Philosophy, University of Akron, Integrated Bioscience.
Within evolutionary biology, the evolution of sexual reproduction has been both a critical theme and a persistent dilemma. The frequency of sexual reproduction in the natural world and the variety of sexual systems point to its adaptiveness despite the genetic costs. A rare sexual system, androdioecy, includes males and hermaphrodites. Although uncommon, where androdioecy occurs it can be persistent, lasting millions of years. Several models have been developed to explain the maintenance of androdioecy as a stable mating system. Stable androdioecy has been proposed as (1) an artifact of the genetic mechanism of sex determination coupled with high levels of inbreeding depression (the Overdominance Model), (2) a result of sexual conflict between males and self-fertilizing hermaphrodites who are resistant to outcrossing (the Sexual Conflict Model), and (3) having an adaptive advantage in fragmented landscapes where connectivity between subpopulations is low (the Metapopulation Model). Herein, these models are tested empirically, using clam shrimp as a model organism, and theoretically using a simulation model. A multigenerational study using Eulimnadia texana determined whether males or male-producing hermaphrodites could invade hermaphrodite-only pools. Both invaded successfully and population sizes subsequently increased, in contradiction to the predictions of the Overdominance and Sexual Conflict models. Next, mating behaviors in Eulimnadia dahli were observed to assess differences in aggressive or resistant behaviors between hermaphrodites and males from “monogenic” (i.e., all hermaphroditic) and “amphigenic” (males/hermaphrodite) populations. Hermaphrodites from monogenic populations were predicted to be more resistant and have fewer outcrossing events than hermaphrodites from amphigenic populations. However, monogenic hermaphrodites outcrossed more often, in contradiction of the Sexual Conflict model. Finally, a simulation was created to model interactions between metapopulation structure and sexual systems. Organisms reproducing via dioecy, androdioecy, or hermaphroditism were seeded separately into metapopulation frameworks to assess the effects of reproductive mode on population attributes over a 100-generation time span. Colonization rates were highest in androdioecy and hermaphroditism. Fitness and inbreeding depression were inversely correlated, with dioecious groups suffering the lowest fitness. Androdioecious metapopulations retained greater genetic variance than the other treatments. Taken together the simulation results provide more support for the Metapopulation model than the others.
Stephen Weeks (Advisor)
Francisco Moore (Committee Member)
Zhong-Hui Duan (Committee Member)
Todd Blackledge (Committee Member)
Randall Mitchell (Committee Member)
103 p.
Animal Sciences; Biology; Computer Science; Evolution and Development; Genetics
mating systems; androdioecy; sex evolution; sexual conflict; hermaphroditism; clam shrimp; Eulimnadia; mating behavior

Recommended Citations

Citations

  • Calabrese, A. (2021). Theoretical and empirical tests of evolutionary models predicting androdioecy to be an evolutionarily stable mating system [Doctoral dissertation, University of Akron]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=akron1637261675658712

    APA Style (7th edition)

  • Calabrese, Alissa. Theoretical and empirical tests of evolutionary models predicting androdioecy to be an evolutionarily stable mating system. 2021. University of Akron, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=akron1637261675658712.

    MLA Style (8th edition)

  • Calabrese, Alissa. "Theoretical and empirical tests of evolutionary models predicting androdioecy to be an evolutionarily stable mating system." Doctoral dissertation, University of Akron, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1637261675658712

    Chicago Manual of Style (17th edition)

akron1637261675658712
112
© 2021, all rights reserved.
This open access ETD is published by University of Akron and OhioLINK.