FIGURE 1. Phylogenetic tree of our extant comparative sample generated using TimeTree (www.timetree.org; Kumar et al., 2017).
FIGURE 2. Boxplots of Dirichlet normal energy (DNE), relief index (RFI), and orientation patch count rotated (OPCR) across extant mammals classified by diet and a subset of fossil groups. Abbreviations for diet categories: ado = animal-dominated omnivore; carn = carnivore; frug = frugivore; inv = invertivore; pdo = plant-dominated omnivore; sis = soft-invertebrate specialist. Abbreviations for fossil groups: Alph. = Alphadontidae; Herpet. = Herpetotheriidae; Ped. = Pediomyidae.
FIGURE 3. Bivariate scatter plots of log-transformed Dirichlet normal energy (lnDNE), relief index (lnRFI), and orientation patch count rotated (lnOPCR) values, and a 3D scatterplot of all three DTA metrics (bottom right) for our extant comparative sample. Shapes correspond to our assigned diet categorizations. See Table 2 for taxonomic names. Abbreviations for diet categories: ado = animal-dominated omnivore; carn = carnivore; frug = frugivore; inv = invertivore; pdo = plant-dominated omnivore; sis = soft-invertebrate specialist.
FIGURE 4. Bivariate scatter plots of log-transformed Dirichlet normal energy (lnDNE), relief index (lnRFI), and orientation patch count rotated (lnOPCR) values, and a 3D scatterplot of all three DTA metrics (bottom right) for our fossil sample. Colored polygons are regions of the morphospace occupied by extant mammals in our dietary categories. Shapes correspond to fossil groups. See Table 3 for taxonomic names. Abbreviations for diet categories: ado = animal-dominated omnivore; carn = carnivore; frug = frugivore; inv = invertivore; pdo = plant-dominated omnivore; sis = soft-invertebrate specialist.
FIGURE 5. Morphological disparity of NALK metatherians during different time bins (top) and in two major subclasses (bottom). We calculated disparity as the variance of each DTA metric and the sum of variances. The 95% confidence intervals were generated using a custom bootstrapping function with 1,000 replicates. Top row: all-metatherian disparity for each time bin. Sample size for each time bin is shown in parentheses at the bottom of the far-left plot: pre-Aquilan (preA) = 7; Aquilan = 8; Judithian = 18; Lancian = 18. Bottom row: disparity of alphadontids vs. disparity of pediomyids. Sample size for each taxon is shown in parentheses at the bottom of the far-left plot: Alphadontidae = 19 and Pediomyidae = 8. See Table 11 for p -values.
FIGURE 6. Patterns of taxonomic diversity and dietary diversity of NALK metatherians. Top: Known taxonomic diversity (gray squares and line) of NALK metatherians and the metatherian diversity sampled in this study (black circles and line). Middle: Dietary diversity of NALK metatherians through time (out of six dietary categories). Judithian diversity count is based on our DFA classification of Iugomortiferum thoringtoni as a carnivore. Bottom: Hypothesized phylogenetic relationships of NALK metatherians sampled in this study (the deltatheriid Atokatheridium boreni was removed). The phylogeny is modified from Williamson et al. (2014), Wilson et al. (2016), and Cohen et al. (2020). Thick horizontal bars represent the known temporal range of each species. Bar colors represent the dietary categories assigned to each taxon in this study. For cases in which specimens of the same species were classified differently, we include both classifications in this figure, with the exception of Iugomortiferum thoringtoni and Didelphodon vorax. Our DFA classification for Iugomortiferum thoringtoni (carn) contradicts additional lines of evidence that suggests it is a plant-dominated omnivore (see Discussion), and thus we classify it here as ‘carn/pdo.’ Our DFA classifies the two Didelphodon vorax specimens as an animal-dominated omnivore and an invertivore, but additional lines of evidence suggest that it is an animal-dominated omnivore (see Discussion). Abbreviations for diet categories: ado = animal-dominated omnivore; carn = carnivore; frug = frugivore; inv = invertivore; pdo = plant-dominated omnivore; sis = soft-invertebrate specialist. Abbreviations for NALMAs: Aquil = Aquilan; La = Lancian.
FIGURE 7. Scatterplots of lnDNE versus lnRFI of NALK metatherians through time. Points represent species averages for each DTA metric. Time proceeds upward with the oldest time bin (pre-Aquilan) at the bottom and the youngest time bin (Lancian) at the top. Colored polygons are regions of the morphospace occupied by extant mammals in our dietary categories. Markers correspond to fossil groups. Abbreviations for diet categories: ado = animal-dominated omnivore; carn = carnivore; frug = frugivore; inv = invertivore; pdo = plant-dominated omnivore; sis = soft-invertebrate specialist.
