Temperature determination of male outcrossing ability in a simultaneous hermaphrodite

Abstract

Phally is a genital dimorphism found in some species of self-compatible simultaneous hermaphrodites. Both aphallics and euphallics can self-fertilize but only euphallics develop a functional penis and prostate allowing them to donate sperm. Previous studies of phally in the gastropod Bulinus truncatus (Mollusca: Pulmonata) suggest that phally may be under direct genetic control in some populations and strongly influenced by environmental factors in others. Experiments identify temperature as a cue affecting phally determination in two populations. A higher proportion of euphallics was produced at low temperature (22 ± 1°C) than at high temperature (30 ± 1°C). -from Authors