Hostname: page-component-7c8c6479df-5xszh Total loading time: 0 Render date: 2024-03-28T17:27:56.752Z Has data issue: false hasContentIssue false

The proximate determinants of sex ratio in C. elegans populations

Published online by Cambridge University Press:  30 April 2003

ASHER D. CUTTER
Affiliation:
Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
LETICIA AVILÉS
Affiliation:
Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
SAMUEL WARD
Affiliation:
Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The soil nematode Caenorhabditis elegans is an example of a species in which self-fertilizing hermaphrodites predominate, but functional males continue to persist – allowing outcrossing to persevere at low levels. Hermaphrodites can produce male progeny as a consequence of sex chromosome non-disjunction or via outcrossing with males. Consequently, the genetics of sex determination coupled with the efficiency by which males find, inseminate and obtain fertilizations with hermaphrodites will influence the frequency at which males and outcrossing occurs in such populations. Behavioural and physiological traits with a heritable basis, as well as ecological characters, may influence male reproductive success and therefore sex ratio. Because sex ratio is tied to male reproductive success, sex ratio greatly affects outcrossing rates, patterns of genetic variation, and the ability of natural selection to act within populations. In this paper we explore the determinants of male frequency in C. elegans with a mathematical model and experimental data. We address the role of the genetic machinery of sex determination via sex chromosome non-disjunction on sex ratio and the influence of physiological components of C. elegans' life history that contribute to variation in sex ratio by way of male reproductive success. Finally, we discuss the short-term and long-term factors that are likely to affect sex ratio and breeding system evolution in species like C. elegans.

Type
Research Article
Copyright
© 2003 Cambridge University Press