Pre and post zygotic fitness components of hybridization in spadefoot toads Public Deposited

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  • March 21, 2019
  • Wojtowicz, Elizabeth
    • Affiliation: College of Arts and Sciences, Department of Biology
  • When hybrids are unfit, selection favors the evolution of pre-mating barriers that impede gene flow and promote population differentiation. Hybrid fitness, however, is complex and may vary across life-stages. Additionally, the costs may differ between species. Using spadefoot toads I examined pre- and post- zygotic fitness components of hybridization. First, I focused on two post-mating pre-zygotic barriers: fertilization success and clutch size. Fertilization success did not differ between conspecific and heterospecific males. Average clutch size did not differ as a result of heterospecific pairing. Therefore, species-specific gamete recognition is absent between these species. Second, I investigated post-zygotic fitness components of hybrid growth and survival in the period immediately following metamorphosis. Data suggests that while hybridization may be beneficial in early development, condition immediately following metamorphosis may lead to decreased survival over time. Hybrids were intermediate in size, suggesting one species may benefit more than the other.
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  • In Copyright
  • Pfennig, Karin
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  • University of North Carolina at Chapel Hill
  • Open access

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