No selection for change in polyandry under experimental evolution

Andreas Sutter, Laura M Travers, Melanie Weedon, Keiko Oku, Thomas A R Price, Nina Wedell

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)
3 Downloads (Pure)

Abstract

What drives mating system variation is a major question in evolutionary biology. Female multiple mating (polyandry) has diverse evolutionary consequences, and there are many potential benefits and costs of polyandry. However, our understanding of its evolution is biased towards studies enforcing monandry in polyandrous species. What drives and maintains variation in polyandry between individuals, genotypes, populations and species remains poorly understood. Genetic variation in polyandry may be actively maintained by selection, or arise by chance if polyandry is selectively neutral. In Drosophila pseudoobscura, there is genetic variation in polyandry between and within populations. We used isofemale lines to found replicate populations with high or low initial levels of polyandry and tracked polyandry under experimental evolution over seven generations. Polyandry remained relatively stable, reflecting the starting frequencies of the experimental populations. There were no clear fitness differences between high versus low polyandry genotypes, and there was no signature of balancing selection. We confirmed these patterns in direct comparisons between evolved and ancestral females and found no consequences of polyandry for female fecundity. The absence of differential selection even when initiating populations with major differences in polyandry casts some doubt on the importance of polyandry for female fitness.

Original languageEnglish
Pages (from-to)717-730
JournalJournal of Evolutionary Biology
Volume32
Issue number7
Early online date10 Apr 2019
DOIs
Publication statusPublished - Jul 2019

Cite this