Lineages evolved under stronger sexual selection show superior ability to invade conspecific competitor populations

Godwin, Joanne L., Spurgin, Lewis G., Michalczyk, Łukasz, Martin, Oliver Y., Lumley, Alyson J., Chapman, Tracey and Gage, Matthew J. G. (2018) Lineages evolved under stronger sexual selection show superior ability to invade conspecific competitor populations. Evolution Letters, 2 (5). pp. 511-523. ISSN 2056-3744

[thumbnail of Published manuscript]
PDF (Published manuscript) - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview


Despite limitations on offspring production, almost all multicellular species use sex to reproduce. Sex gives rise to sexual selection, a widespread force operating through competition and choice within reproduction, however, it remains unclear whether sexual selection is beneficial for total lineage fitness, or if it acts as a constraint. Sexual selection could be a positive force because of selection on improved individual condition and purging of mutation load, summing into lineages with superior fitness. On the other hand, sexual selection could negate potential net fitness through the actions of sexual conflict, or because of tensions between investment in sexually selected and naturally selected traits. Here, we explore these ideas using a multigenerational invasion challenge to measure consequences of sexual selection for the overall net fitness of a lineage. After applying experimental evolution under strong versus weak regimes of sexual selection for 77 generations with the flour beetle Tribolium castaneum, we measured the overall ability of introductions from either regime to invade into conspecific competitor populations across eight generations. Results showed that populations from stronger sexual selection backgrounds had superior net fitness, invading more rapidly and completely than counterparts from weak sexual selection backgrounds. Despite comprising only 10% of each population at the start of the invasion experiment, colonizations from strong sexual selection histories eventually achieved near‐total introgression, almost completely eliminating the original competitor genotype. Population genetic simulations using the design and parameters of our experiment indicate that this invasion superiority could be explained if strong sexual selection had improved both juvenile and adult fitness, in both sexes. Using a combination of empirical and modeling approaches, our findings therefore reveal positive and wide‐reaching impacts of sexual selection for net population fitness when facing the broad challenge of invading competitor populations across multiple generations.

Item Type: Article
Uncontrolled Keywords: experimental evolution,genic capture,introgression,mutation load,population fitness,tribolium
Faculty \ School: Faculty of Science > School of Biological Sciences
UEA Research Groups: Faculty of Science > Research Centres > Centre for Ecology, Evolution and Conservation
Faculty of Science > Research Groups > Organisms and the Environment
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 26 Sep 2018 14:30
Last Modified: 25 Aug 2023 00:23
DOI: 10.1002/evl3.80

Actions (login required)

View Item View Item