Strong asymmetry in the relative strengths of prezygotic and postzygotic barriers between two damselfly sister species
Author
Summary, in English
One of the longest debates in biology has been over the relative importance of different isolating barriers in speciation. However, for most species, there are few data evaluating their relative contributions and we can only speculate on the general roles of pre- and postzygotic isolation. Here, we quantify the absolute and cumulative contribution of 19 potential reproductive barriers between two sympatric damselfly sister species, Ischnura elegans and I. graellsii, including both premating (habitat, temporal, sexual and mechanical isolation) and postmating barriers (prezygotic: sperm insemination success and removal rate, oviposition success, fertility, fecundity; postzygotic: hybrid viability, hybrid sterility and hybrid breakdown). In sympatry, total reproductive isolation between I. elegans females and I. graellsii males was 95.2%, owing mostly to a premating mechanical incompatibility (93.4%), whereas other barriers were of little importance. Isolation between I. graellsii females and I. elegans males was also nearly complete (95.8%), which was caused by the cumulative action of multiple prezygotic (n= 4, 75.4%) and postzygotic postmating barriers (n= 5, 7.4%). Our results suggest that premating barriers are key factors in preventing gene flow between species, and that the relative strengths of premating barriers is highly asymmetrical between the reciprocal crosses.
Department/s
Publishing year
2012
Language
English
Pages
690-707
Publication/Series
Evolution
Volume
66
Issue
3
Links
Document type
Journal article
Publisher
Wiley-Blackwell
Topic
- Evolutionary Biology
Status
Published
Project
- Hybridisation in damselflies
Research group
- Molecular Ecology and Evolution Lab
ISBN/ISSN/Other
- ISSN: 1558-5646