Figure 6.
Speciation, Polyploidy, and Lineage Separation Events in the Brassicaceae Presented in Phylogenetic Context.
Brassicaceae chronogram adapted from Beilstein et al. (2010) was slightly modified by adjusting the branch lengths to reflect the ages of major polyploidy and lineage separation events. The positions of the well-known ancient α and β paleopolyploidy events in relation to various lineage divergence events are indicated. The positions of recent speciation and subsequent neo/mesopolyploidy events experienced by various Brassicaceae and a Cleomaceae species are indicated with dark colored ovals. The ages of previously inferred mesopolyploidy events in Australian Brassicaceae species (indicated with red colored asterisks) were recalculated based on the synonymous substitution values of the three nuclear genes reported by Mandáková et al. (2010a) and the calibrated synonymous substitution rate of 8.22 × 10−9. Numbers in parenthesis indicate estimated age of the speciation of parental diploids of each neo/mesopolyploid species. The actual neo/mesopolyploidization in these species may have occurred anytime between the age of speciation mentioned in brackets and the current day. E. Cretaceous, early Cretaceous; L. Cretaceous, late Cretaceous; Pal, Paleocene; Oligo, Oligocene; Pl, Pliocene; Q, Quarternary.