Phylogenetic autocorrelation among brain measures.

<p>Degree of phylogenetic autocorrelation in relative brain volume measures using Blomberg’s k. K is the degree of phylogenetic signal, Z is the position in the Z distribution estimated from a tip rearrangement test using 100,000 iterations, and p is the p-value estimated from the tip rearrangement test.</p

Phylogenetic autocorrelation as measured using Moran’s I, which ranges between

<p>−<b>1 and 1.</b> Black circles indicate statistically significant autocorrelation at α≤0.05, and grey circles indicate measures that are not significant at α≤0.05.</p

Box plot showing relationship between diet and relative endocranial volume.

<p>Boxes indicate interquartile ranges, and whiskers spread to the furthest points outside the interquartile range, but within 1.5 times the interquartile range from the median.</p

PGLS regression outputs for all variables other than diet.

<p>Multiple regression output for the best model for each of the different response variables, not including effects of diet, because diet is categorical. Body SCI is the size change index for body mass or skull size. Brain SCI is the size change index for brain volume. Sociality is PC1 from the PCA of the variables describing social complexity. Home range is log home range size corrected for body size in the same way as brain volume. Forelimb use is our measure of forelimb dexterity. Finally, life history is PC1 from a PCA of the three life history variables we included in our analysis.</p

Carnivore phylogeny, demonstration of size-change indices, and relative endocranial volumes by family.

<p>a) Carnivore phylogeny with Pagel’s arbitrary branch lengths. Filled circles represent the hypothetical ancestors or nodes at which the ancestral traits were estimated. Heavy lines link each extant species to the ancestral node that was subtracted from the value for the extant species to obtain size change indices (SCIs). b) Demonstration of how SCIs were calculated. Most recent estimated ancestral size values (ASV) were subtracted from the associated value for extant species size (ESV), and the difference is equal to the SCI. c) Box-and-whisker plot displaying degree of variation in relative brain size within each family. Relative MCOEV is indicated by a white box and relative SCOEV by a grey box. Boxes indicate interquartile range, and whiskers spread to the furthest points outside the interquartile range, but within 1.5 times the interquartile range from the median.</p

Effects of diet on relative endocranial measures.

<p>Effects of diet from ANOVAs, and contrasts from multiple regressions. For the contrasts, C represents carnivore, O represents omnivore and I represents insectivore. In each case, the first species is the one being contrasted. For example, I vs. C means that the estimate of effect under β is the change in the response variable due to insectivory with carnivores as the intercept. Note that diet effects were estimated as part of the multiple regression results in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038447#pone-0038447-t003" target="_blank">Table 3</a>, and are in a separate table only for presentation purposes.</p