Gynodioecy is a sexual system in which females and hermaphrodites co‐occur. In most gynodioecious angiosperms, sex is determined by an interaction between mitochondrial male‐sterility genes ( To test for balancing selection and/or the repeated introduction of novel We confirmed that mitotype diversity and female frequency were positively correlated across populations, consistent with balancing selection. However, while low‐female populations hosted mostly common mitotypes, high‐female populations and female plants hosted mostly rare, recombinant mitotypes likely to carry novel Our results suggest that balancing selection maintains established
The persistence of populations declining from novel stressors depends, in part, on their ability to respond by trait change via evolution or plasticity. White‐nose syndrome ( We examined whether persistence of We measured body fat in early and late winter during initial Infection prevalence was not significantly lower than observed in declining populations. However, at two sites, infection loads were lower than observed in declining populations. Body fat in early winter was significantly higher in four of the six persisting populations than during Physiological models of energy use indicated that these higher fat stores could reduce
- PAR ID:
- 10461265
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Animal Ecology
- Volume:
- 88
- Issue:
- 4
- ISSN:
- 0021-8790
- Page Range / eLocation ID:
- p. 591-600
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary CMS ) that arise via recombination and nuclear restorer alleles that evolve to suppress them. In theory, gynodioecy occurs when multipleCMS types are maintained at equilibrium frequencies by balancing selection. However, some gynodioecious populations contain very high frequencies of females. High female frequencies are not expected under balancing selection, but could be explained by the repeated introduction of novelCMS types.CMS , we characterised cytoplasmic haplotypes from 61 populations ofLobelia siphilitica that vary widely in female frequency.CMS types.CMS types across this species, but extreme female frequencies result from frequent invasion by novelCMS types. We conclude that balancing selection alone cannot account for extreme population sex‐ratio variation within a gynodioecious species. -
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