Open AccessSelection and Maintenance of Androdioecy in Caenorhabditis elegans
Author(s) -
Andrew D. Stewart,
Patrick C. Phillips
Publication year - 2002
Publication title -
genetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.792
H-Index - 246
eISSN - 1943-2631
pISSN - 0016-6731
DOI - 10.1093/genetics/160.3.975
Subject(s) - biology , selfing , inbreeding depression , genetics , caenorhabditis elegans , population , mating , outcrossing , inbreeding , mating system , evolutionary biology , ecology , gene , demography , pollen , sociology
Caenorhabditis elegans is an androdioecious nematode composed of selfing hermaphrodites and rare males. A model of male maintenance demonstrates that selfing rates in hermaphrodites cannot be too high or else the frequency of males will be driven down to the rate of spontaneous nondisjunction of the X chromosome. After their outcrossing ability is assessed, males are found to skirt the frequency range in which they would be maintained. When male maintenance is directly assessed by elevating male frequency and observing the frequency change through time, males are gradually eliminated from the population. Males, therefore, appear to reproduce at a rate just below that necessary for them to be maintained. Populations polymorphic for a mutation (fog-2) that effectively changes hermaphrodites into females demonstrate that there is strong selection against dioecy. Factors such as variation in male mating ability and inbreeding depression could potentially lead to the long-term maintenance of males.