Evolution of increased self-sperm production in postdauer hermaphroditic nematodes

Abstract

A recent study suggests that postdauer Caenorhabditis elegans hermaphrodites produce more self-sperm and have larger brood sizes than worms that bypass diapause. Why might natural selection favor increased self-sperm production in postdauer hermaphrodites? This question is addressed by developing an age-structured model for an exponentially growing worm population descending from a founder postdauer hermaphrodite. It is assumed that natural selection favors those founders that have the largest number of living descendants at some fixed future time. Increased self-sperm production in postdauer hermaphrodites can then evolve when the diapause-bypassing descendants suffer a higher mortality rate than their parental postdauer founders. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution..