Results of rank correlations, Spearman's rho (<i>ρ</i>) and Kendall's tau (<i>τ</i>), for global age ranks.

<p>Results of rank correlations, Spearman's rho (<i>ρ</i>) and Kendall's tau (<i>τ</i>), for global age ranks.</p

Phylogenetic model fitting results.

<p>Model selection based on comparison of corrected AICs and Akaike weights (AW) for Brownian motion (BM), Brownian motion with trend (BM_T), Ornstein-Uhlenbeck (OU), and early burst (EB) models;</p><p>AICc, Akaike's Information Criterion corrected for small sample size; AW, Akaike weight;</p><p><i>β</i>, BM rate parameter; <i>μ</i>, step mean; <i>θ</i>, trait mean; <i>α</i>, constraint parameter; <i>r</i>, decay rate;</p><p>bold = best model; italics = non-negligible model (AW ≥1/8 best model).</p

Ancestral state reconstructions for basal skull length in Permian and Triassic cynodonts.

<p>Colored horizontal bars indicate ranges of tip taxa spanning more than one stratigraphic bin (e.g., <i>Procynosuchus</i>, <i>Cynosaurus</i>). Permian-Triassic boundary indicated by dashed line. Abbreviations: CiAZ, <i>Cistecephalus</i> Assemblage Zone; CynAZ, <i>Cynognathus</i> Assemblage Zone; DAZ, <i>Dicynodon</i> Assemblage Zone; LAZ, <i>Lystrosaurus</i> Assemblage Zone.</p

Cladograms subsampled from five stratigraphic bins for analysis of diversification rate shifts. A

<p>, <i>Tropidostoma</i> Assemblage Zone. <b>B</b>, <i>Cistecephalus</i> Assemblage Zone. <b>C</b>, <i>Dicynodon</i> Assemblage Zone. <b>D</b>, <i>Lystrosaurus</i> Assemblage Zone. <b>E</b>, <i>Cynognathus</i> Assemblage Zone. Gray branches represent ghost lineages for terminal taxa or clades that appear in a succeeding stratigraphic interval. Numbers at nodes represent <i>p</i>-values near or below 0.05 for the Δ₁ (top) and Δ₂ (bottom) statistics. Significant shifts are observed along the branch between the node of Eutherocephalia and non-<i>Scylacosuchus</i> eutherocephalians for the <i>Tropidostoma</i> AZ subsample (A), and a marginally significant shift is observed along the branch between Eutheriodontia and Eutherocephalia for the <i>Cistecephalus</i> AZ (B).</p

Time series model fitting of body size evolution in Karoo therocephalians and cynodonts.

<p>GRW, generalized random walk (directional); URW, unbiased random walk;</p><p>AICc, Akaike's Information Criterion corrected for small sample size; AW, Akaike weight;</p><p><i>μ</i>, step mean; <i>σ²</i>, step variance; <i>θ</i>, trait mean; <i>ω</i>, trait variance;</p><p>bold = best model; italics = non-negligible model (AW ≥1/8 best model).</p

Complete reference cladogram with nodes numbered for estimation of patristic distances.

<p>Sources include: therocephalians, Huttenlocker <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Huttenlocker2" target="_blank">[54]</a>, Huttenlocker et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Huttenlocker1" target="_blank">[33]</a>, Sigurdsen et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Sigurdsen1" target="_blank">[55]</a>; cynodonts, Hopson & Kitching <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Hopson1" target="_blank">[56]</a>, Abdala et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Abdala1" target="_blank">[45]</a>, Sidor & Hancox <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Sidor3" target="_blank">[57]</a>, Ranivoharimanana et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Ranivoharimanana1" target="_blank">[60]</a>, Oliveira et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Oliveira1" target="_blank">[58]</a>, Liu & Olsen <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087553#pone.0087553-Liu1" target="_blank">[59]</a>.</p

Results of rank correlations, Spearman's rho (<i>ρ</i>) and Kendall's tau (<i>τ</i>), for clade ranks and patristic distances.

<p>Results of rank correlations, Spearman's rho (<i>ρ</i>) and Kendall's tau (<i>τ</i>), for clade ranks and patristic distances.</p

Traitgram of body size evolution in a global sample of Permian through Triassic eutheriodonts, approximating an ‘early burst’ Brownian process (EB) of trait evolution.

<p>Arrow denotes location of <i>Lystrosaurus</i> Assemblage Zone taxa along the time-axis. Graphic created using the <i>traitgram()</i> function in ‘picante.’</p

Spearman's rank correlation tests on clade rank (A, B) and patristic distance (C) versus maximum basal skull length for the global dataset of Middle Permian through Late Triassic eutheriodonts.

<p>Solid circles represent Permian taxa (therocephalian subclade = blue; cynodont subclade = gold), open diamonds represent Early Triassic <i>Lystrosaurus</i> Assemblage Zone (LAZ) taxa, and open circles represent Triassic post-LAZ taxa.</p

Ancestral state reconstructions for basal skull length in Permian and Triassic therocephalians.

<p>Colored horizontal bars indicate ranges of tip taxa spanning more than one stratigraphic bin. Note that significant decreases in mean sizes of major subgroups across the Permian-Triassic boundary (dashed line) were associated with the loss of large-bodied taxa and the survival of pre-existing small-bodied taxa or clades. Abbreviations: CiAZ, <i>Cistecephalus</i> Assemblage Zone; CynAZ, <i>Cynognathus</i> Assemblage Zone; DAZ, <i>Dicynodon</i> Assemblage Zone; LAZ, <i>Lystrosaurus</i> Assemblage Zone.</p