IngentaConnect Genetic variation and asexual reproduction in the facultatively p...

Authors: Corley, L. S.¹; Blankenship, J. R.²; Moore, A. J.³

Source: Journal of Evolutionary Biology, Volume 14, Number 1, January 2001 , pp. 68-74(7)

Abstract:

Asexual reproduction could offer up to a two-fold fitness advantage over sexual reproduction, yet higher organisms usually reproduce sexually. Even in facultatively parthenogenetic species, where both sexual and asexual reproduction is sometimes possible, asexual reproduction is rare. Thus, the debate over the evolution of sex has focused on ecological and mutation-elimination advantages of sex. An alternative explanation for the predominance of sex is that it is difficult for an organism to accomplish asexual reproduction once sexual reproduction has evolved. Difficulty in returning to asexuality could reflect developmental or genetic constraints. Here, we investigate the role of genetic factors in limiting asexual reproduction in Nauphoeta cinerea, an African cockroach with facultative parthenogenesis that nearly always reproduces sexually. We show that when N. cinerea females do reproduce asexually, offspring are genetically identical to their mothers. However, asexual reproduction is limited to a nonrandom subset of the genotypes in the population. Only females that have a high level of heterozygosity are capable of parthenogenetic reproduction and there is a strong familial influence on the ability to reproduce parthenogenetically. Although the mechanism by which genetic variation facilitates asexual reproduction is unknown, we suggest that heterosis may facilitate the switch from producing haploid meiotic eggs to diploid, essentially mitotic, eggs.

Keywords: developmental constraints; evolution of sex; heterozygosity; quantitative genetics

Document Type: Research article

DOI: 10.1046/j.1420-9101.2001.00254.x

Affiliations: 1: Department of Entomology, University of Wisconsin, Madison, WI 53706, USA 2: Department of Genetics, Duke University, Durham, NC 27710, USA 3: School of Biological Sciences, University of Manchester, Manchester M13 9PT, UK

You have access to the full text article on a website external to Ingentaconnect.

Please click here to view this article on InterScience.

You may be required to register and activate access on InterScience before you can obtain the full text. If you have any queries please contact onlinehelp@oxon.blackwellpublishing.com

Genetic variation and asexual reproduction in the facultatively parthenogenetic cockroach Nauphoeta cinerea: implications for the evolution of sex