Multiple paternity in wild house mice (Mus musculus musculus): effects on offspring genetic diversity and body mass
Article first published online: 22 DEC 2013
© 2013 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Ecology and Evolution
Volume 4, Issue 2, pages 200–209, January 2014
How to Cite
Ecology and Evolution 2014; 4(2):200–209.
- Issue published online: 20 JAN 2014
- Article first published online: 22 DEC 2013
- Manuscript Accepted: 14 NOV 2013
- Manuscript Revised: 12 NOV 2013
- Manuscript Received: 19 AUG 2013
- Austrian Science Fund (FWF). Grant Number: P 24711-B21
- Genetic benefits;
- genetic diversity;
- house mice;
- multiple paternity
Multiple mating is common in many species, but it is unclear whether multiple paternity enhances offspring genetic diversity or fitness. We conducted a survey on wild house mice (Mus musculus musculus), and we found that in 73 pregnant females, 29% of litters had multiple sires, which is remarkably similar to the 23–26% found in feral populations of Mus musculus domesticus in the USA and Australia, respectively. The question is: How has selection maintained multiple mating in these subspecies since the evolutionary divergence, ca. 2800–6000 years ago? We found no evidence that multiple paternity enhanced females’ litter size, contrary to the fertility assurance or genetic benefits hypotheses. Multiple paternity was associated with reduced mean and variance in offspring body mass, which suggests that females allocate fewer resources or that there is increased intrauterine conflict in multiple- versus single-sired litters. We found increased allelic diversity (though not heterozygosity) in multiple-sired litters, as predicted by the genetic diversity hypothesis. Finally, we found that the dams’ heterozygosity was correlated with the mean heterozygosity of their offspring in single- and multiple-sired litters, suggesting that outbred, heterozygous females were more likely to avoid inbreeding than inbred, homozygous females. Future studies are needed to examine how increased genetic diversity of litters and smaller mean (and variance) offspring body mass associated with multiple paternity affect offspring fitness.