Fig. 1: Theoretical framework for the evolution of sexual systems.
From: Switches, stability and reversals in the evolutionary history of sexual systems in fish
Illustration of potential evolutionary transitions between gonochorism (in grey) and simultaneous hermaphroditism (in yellow) via mixed systems (mixed pathways) as described in plants and some animals; via sequential hermaphroditism (sequential pathways: protogyny in red and protandry in blue) as recently suggested4; or without intermediate states (direct pathways) as proposed for plants6. Double-headed arrows indicate theoretical pathways.
