Sex as a strategy against rapidly evolving parasites

Alternative title Sex as a weapon against parasitism



Auld SKJR, Tinkler SK & Tinsley MC (2016) Sex as a strategy against rapidly evolving parasites [Sex as a weapon against parasitism]. Proceedings of the Royal Society B: Biological Sciences, 283 (1845), Art. No.: 20162226.

Why is sex ubiquitous when asexual reproduction is much less costly? Sex disrupts coadapted gene complexes; it also causes costs associated with mate finding and the production of males who do not themselves bear offspring. Theory predicts parasites select for host sex because genetically variable offspring can escape infection from parasites adapted to infect the previous generations. We examine this using a facultative sexual crustacean, Daphnia magna, and its sterilising bacterial parasite, Pasteuria ramosa. We obtained sexually and asexually produced offspring from wild-caught hosts and exposed them to contemporary parasites or parasites isolated from the same population one year later. We found rapid parasite adaptation to replicate within asexual but not sexual offspring. Moreover, sexually produced offspring were twice as resistant to infection as asexuals when exposed to parasites that had coevolved alongside their parents (i.e., the year 2 parasite). This fulfils the requirement that the benefits of sex must be both large and rapid for sex to be favoured by selection.

evolution of sex; Red Queen; parasitism; coevolution

Proceedings of the Royal Society B: Biological Sciences: Volume 283, Issue 1845

FundersNatural Environment Research Council
Publication date28/12/2016
Publication date online21/12/2016
Date accepted by journal18/11/2016
PublisherRoyal Society

People (1)


Professor Matthew Tinsley

Professor Matthew Tinsley

Professor, Biological and Environmental Sciences

Projects (1)