Fitness and the level of homozygosity in a social insect

C Haag-Liautard, Emma Vitikainen, L Keller, Liselotte Sundström

    Research output: Contribution to journalArticleScientificpeer-review

    Abstract

    To date very few studies have addressed the effects of inbreeding in social Hymenoptera, perhaps because the costs of inbreeding are generally considered marginal owing to male haploidy whereby recessive deleterious alleles are strongly exposed to selection in males. Here, we present one of the first studies on the effects of queen and worker homozygosity on colony performance. In a wild population of the ant Formica exsecta, the relative investment of single-queen colonies in sexual production decreased with increased worker homozygosity. This may either stem from increased homozygosity decreasing the likelihood of diploid brood to develop into queens or a lower efficiency of more homozygous workers at feeding larvae and thus a lower proportion of the female brood developing into queens. There was also a significant negative association between colony age and the level of queen but not worker homozygosity. This association may stem from inbreeding affecting queen lifespan and/or their fecundity, and thus colony survival. However, there was no association between queen homozygosity and colony size, suggesting that inbreeding affects colony survival as a result of inbred queens having a shorter lifespan rather than a lower fecundity. Finally, there was no significant association between either worker or queen homozygosity and the probability of successful colony founding, colony size and colony productivity, the three other traits studied. Overall, these results indicate that inbreeding depression may have important effects on colony fitness by affecting both the parental (queen) and offspring (worker) generations cohabiting within an ant colony.
    Original languageEnglish
    JournalJournal of Evolutionary Biology
    Volume22
    Issue number1
    Pages (from-to)134-142
    Number of pages9
    ISSN1010-061X
    DOIs
    Publication statusPublished - 2009
    MoE publication typeA1 Journal article-refereed

    Fields of Science

    • 1181 Ecology, evolutionary biology

    Cite this