ENVIRONMENTAL STRESS AND THE MAINTENANCE OF SEX IN A FRESHWATER SNAIL

Curtis M Lively; Emily J Lyons; A D Peters; Jukka Jokela

doi:10.1111/j.1558-5646.1998.tb02029.x

ENVIRONMENTAL STRESS AND THE MAINTENANCE OF SEX IN A FRESHWATER SNAIL

Evolution. 1998 Oct;52(5):1482-1486. doi: 10.1111/j.1558-5646.1998.tb02029.x.

Authors

Curtis M Lively¹, Emily J Lyons¹, A D Peters¹, Jukka Jokela²

Affiliations

¹ Department of Biology, Indiana University, Bloomington, Indiana, 47405.
² Experimental Ecology, ETH-Zürich, ETH-Zentrum NW, CH-8092, Zürich, Switzerland.

PMID: 28565402
DOI: 10.1111/j.1558-5646.1998.tb02029.x

Abstract

Synergism among mutations can lead to an advantage to sexual reproduction, provided mutation rates are high enough (the mutational deterministic hypothesis). Here we tested the idea that competition for food can increase the advantage to sexual reproduction, perhaps by increasing the synergism among mutations in asexual individuals. We compared the survivorship of sexual and asexual snails (Potamopyrgus antipodarum) under two treatments: starved and fed. We predicted higher mortality for asexual snails when starved, but found that sexual and asexual individuals survived at the same rate, independent of treatment. These results suggest that the distribution of sex in this snail may not be explained by variation in competition among populations.

Keywords: Competition; Potamopyrgus antipodarum; environmental stress; geographic parthenogenesis; mutational deterministic hypothesis; sexual reproduction.