Reduced sperm performance in backcross hybrids between species pairs of whitefish (Coregonus clupeaformis)

A. R. Whiteley, K. N. Persaud, N. Derome, R. Montgomerie, L. Bernatchez

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


Previous work has demonstrated that genomic incompatibilities work together with ecologically divergent selection to promote and maintain reproductive isolation between incipient species (dwarf and normal) of lake whitefish (Coregonus clupeaformis (Mitchill, 1818)). Whitefish spawn in groups with external fertilization, which creates conditions for strong sperm competition. In this study, we asked whether reduced sperm performance in hybrids from whitefish speciespair matings might contribute to postzygotic isolating mechanisms between these taxa. We examined two sperm traits, sperm swimming speed and flagellum length, in pure dwarf and normal whitefish and in their F1 and backcross hybrids. We observed significantly reduced sperm swimming speed in backcross but not in F1 hybrids. Sperm flagellum length was not significantly correlated with sperm swimming speed. These results demonstrate that F1 hybrids formed in nature should be capable of the same fertilization success as the parental species during sperm competition, everything else being equal. However, reduced sperm performance in the backcross generation is consistent with other evidence suggesting that genomic incompatibilities create a range of negative fitness effects in post-F1 whitefish hybrids and provides evidence for an additional postzygotic isolation mechanism involved in the incipient speciation of sympatric dwarf and normal whitefish.

Original languageEnglish
Pages (from-to)566-572
Number of pages7
JournalCanadian Journal of Zoology
Issue number7
StatePublished - Jul 2009


Dive into the research topics of 'Reduced sperm performance in backcross hybrids between species pairs of whitefish (Coregonus clupeaformis)'. Together they form a unique fingerprint.

Cite this