Fig. 4.

Independent contrasts for body size and MA, showing shifts in these traits for extinction victims (either individual genera or higher clades) relative to their nearest surviving relatives. Patterns recovered from analyses of phylogenetically uncorrected data predict that points should be clustered in the shaded quadrant (i.e., victims should have larger body sizes and lower MA values). Shifts are significantly biased toward decreased MA for both datasets (gradual, P = 0.011; punctuated, P = 0.022; one-tailed t test), but neither demonstrates a significant bias in body-size shifts (gradual, P = 0.19; punctuated, P = 0.51; one-tailed t test).