Fig. 4

Conservation of generation bias across the Ectocarpales (Ectocarpus sp. and S. lomentaria) and Laminariales (S. japonica and M. pyrifera). a Pairwise single orthologs (PSOs) in Ectocarpales and Laminariales. Genes with conserved gametophyte (yellow) or sporophyte bias (blue) exhibited the same bias in the same generation in the two species. Genes with “discordant bias” (green) were gametophyte-biased in one species and sporophyte-biased in the other species. “Gain/loss of bias” genes (pink) were generation-biased in one species but not in the other species. Unbiased PSOs are shown in gray. b Overall level of generation-biased expression (log2FC) for PSOs that are conserved versus PSOs that gained bias in Ectocarpales and Laminariales. c Representations of generation-biased gene gain/loss events across the branches of the Ectocarpales and Laminariales phylogeny. Expected numbers of events are based on multiple stochastic mappings (see the “Methods” section for detail)