Plant mating systems play a key role in structuring genetic variation both within and between species. In hybrid zones, the outcomes and dynamics of hybridization are usually interpreted as the balance between gene flow and selection against hybrids. Yet, mating systems can introduce selective forces that alter these expectations; with diverse outcomes for the level and direction of gene flow depending on variation in outcrossing and whether the mating systems of the species pair are the same or divergent. We present a survey of hybridization in 133 species pairs from 41 plant families and examine how patterns of hybridization vary with mating system. We examine if hybrid zone mode, level of gene flow, asymmetries in gene flow and the frequency of reproductive isolating barriers vary in relation to mating system/s of the species pair. We combine these results with a simulation model and examples from the literature to address two general themes: (1) the two-way interaction between introgression and the evolution of reproductive systems, and (2) how mating system can facilitate or restrict interspecific gene flow. We conclude that examining mating system with hybridization provides unique opportunities to understand divergence and the processes underlying reproductive isolation.
Bibliographical noteFunding Information:
MP was supported by funding from the European Union's Seventh Framework Programme (FP7/2007‐2013) under grant agreement number 329960, CF an Austrian Science Foundation FWF grant (Project M 2463‐B29), SY an NSERC Banting Fellowship and YB an NSF DEB grant number 1754246. TD and EC were supported by the IST Austria Intern programme.
MP was supported by funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement number 329960, CF an Austrian Science Foundation FWF grant (Project M 2463-B29), SY an NSERC Banting Fellowship and YB an NSF DEB grant number 1754246. TD and EC were supported by the IST Austria Intern programme.
© 2019 The Authors. New Phytologist © 2019 New Phytologist Trust
- gene flow
- mating system
- reproductive isolation