Figure 3. Chronogram. The maximum clade credibility tree amongst 9000 in Vicariance and convergence in Magellanic and New Zealand long-looped brachiopod clades (Pan-Brachiopoda: Terebratelloidea)

Figure 3. Chronogram. The maximum clade credibility tree amongst 9000 trees from an uncorrelated lognormal relaxed clock analysis of the rDNA alignment. Nodes are labelled A–R and show mean node ages and 95% highest posterior density (HPD) ranges as wide black bars. See Table 1 for details of SDmean, 95% HPD confidence limits of mean ages, descriptions of nodes and of mean age agreement with external ages. Vertical lines labelled NZ (New Zealand), MAG (Magellanic), Laq (laqueoid) and Short (short-looped terebratulidine) mark the respective clades and the proximate and more distant outgroups. Evolutionary model for dating analysis: 18 taxa, 2833 sites, general time reversible with estimated frequency of invariant sites and gamma rate distribution (four rate categories) with empirical base frequencies; uncorrelated lognormal distribution. Priors: substitution rates, Jefferies; site model alpha and invariant, Normal, mean = 0.7, SD = 0.1, initial = 0.7; tree model root height, lognormal logx mean = 2.39, SD = 0.5; defined taxon sets, default tree prior. Markov chain Monte Carlo chain 107 cycles, sampled every 103. TreeAnnotator was used to identify the maximum clade credibility tree of 9000 trees after 1001 trees were discarded as burnin.