Fig. 1: Phylogeny of the eight species of brown algae investigated.

The approximate estimated ages of the nodes are based on ref. 34 and O. de Clerck (personal communication). A schematic view of typical gamete size differences (female in red and male in blue) for each species pair is presented. Dioicous species (D) are marked in brown and monoicous species (M) in black. Ma, million years ago.