Abstract
BackgroundReproductive interference can mediate interference competition between species through sexual interactions that reduce the fitness of one species by another. Theory shows that the positive frequency-dependent effects of such costly errors in mate recognition can dictate species coexistence or exclusion even with countervailing resource competition differences between species. While usually framed in terms of pre-mating or post-zygotic costs, reproductive interference manifests between individual Caenorhabditis nematodes from negative interspecies gametic interactions: sperm cells from interspecies matings can migrate ectopically to induce female sterility and premature death. The potential for reproductive interference to exert population level effects on Caenorhabditis trait evolution and community structure, however, remains unknown.ResultsHere we test whether a species that is superior in individual-level reproductive interference (C. nigoni) can exact negative demographic effects on competitor species that are superior in resource competition (C. briggsae and C. elegans). We observe coexistence over six generations and find evidence of demographic reproductive interference even under conditions unfavorable to its influence. C. briggsae and C. elegans show distinct patterns of reproductive interference in competitive interactions with C. nigoni.ConclusionsThese results affirm that individual level negative effects of reproductive interference mediated by gamete interactions can ramify to population demography, with the potential to influence patterns of species coexistence separately from the effects of direct resource competition.
Highlights
Reproductive interference can mediate interference competition between species through sexual interactions that reduce the fitness of one species by another
To test whether harm induced by C. nigoni male sperm affects other species at the demographic level, we assessed populations of C. elegans or C. briggsae mixed with C. nigoni
We confirmed that the intrinsic population growth rate of the obligately outcrossing species C. nigoni is lower than the population growth rate of both
Summary
Reproductive interference can mediate interference competition between species through sexual interactions that reduce the fitness of one species by another. Reproductive interference (RI) can result from reduced fitness in one or both species through direct harm, wasted time or energy, or forfeited gametes from interspecies sexual interactions as a form of interference competition [7,8,9]. Similar to other interspecies interactions, RI can influence community structure and evolutionary trajectories from species displacement versus coexistence, specialization (e.g. spatial, temporal, or habitat), and reproductive character displacement [7, 10, 11]. Even if interspecies sexual interactions affect individual fitness (‘component RI’), theory shows that community characteristics are not guaranteed to be perturbed (‘demographic RI’) [10]; if demographic RI occurs, some mechanism of component RI must be present [10]. It is crucial to determine the incidence of both component and
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
