Data for: Reproductive isolating mechanisms contributing to asymmetric hybridization in Killifishes (Fundulus spp.)
Cite this dataset
MacPherson, Nathalie; Champion, Chloe; Weir, Laura; Dalziel, Anne (2022). Data for: Reproductive isolating mechanisms contributing to asymmetric hybridization in Killifishes (Fundulus spp.) [Dataset]. Dryad. https://doi.org/10.5061/dryad.xwdbrv1h8
When species hybridize, one F1 hybrid cross type often predominates. Such asymmetry can arise from differences in a variety of reproductive barriers, but the relative roles and concordance of pre-mating, post-mating prezygotic barriers, and post-zygotic barriers in producing these biases in natural animal populations have not been widely investigated. Here, we study a population of predominantly F1 hybrids between two killifish species (Fundulus heteroclitus and Fundulus diaphanus) in which >95% of F1 hybrids have F. diaphanus mothers and F. heteroclitus fathers (D♀×H♂). To determine why F. heteroclitus x F. diaphanus F1 hybrids (H♀×D♂) are so rare, we tested for asymmetry in pre-mating reproductive barriers (female preference, male aggression) at a common salinity (10 ppt) and post-mating, pre-zygotic (fertilization success) and post-zygotic (embryonic development time and hatching success) reproductive barriers at a range of ecologically relevant salinities (0, 5, 10, and 15 ppt). We found that F. heteroclitus females preferred conspecific males, while F. diaphanus females did not, matching the observed cross bias in the wild. Naturally rare H♀×D♂ crosses also had lower fertilization success than all other cross types, and a lower hatching success than the prevalent D♀×H♂ crosses at the salinity found in the hybrid zone centre (10 ppt). Furthermore, the naturally predominant D♀×H♂ crosses had a higher hatching success than F. diaphanus crosses at 10ppt, which may affect their relative abundance. The present study suggests that a combination of incomplete mating, post-mating pre-zygotic and post-zygotic reproductive isolating mechanisms act in concert to produce hybrid asymmetry in this system.
All analyses conduced in R.
Natural Sciences and Engineering Research Council