The relationship between diversity and disparity during the evolutionary history of a clade provides
unique insights into evolutionary radiations and the biological response to bottlenecks and to
extinctions. Here we present the first comprehensive comparison of diversity and disparity of
captorhinids, a group of basal amniotes that is important for understanding the early evolution of
high-fiber herbivory. A new fully resolved phylogeny is presented, obtained by the inclusion of 31
morphometric characters. The new dataset is used to calculate diversity and disparity through the
evolutionary history of the clade, using both discrete and continuous characters. Captorhinids do
not show a decoupling between diversity and disparity, and are characterized by a rather symmetric
disparity distribution, with a peak in occupied morphospace at about the midpoint of the clade’s
evolutionary history (Kungurian). This peak represents a delayed adaptive radiation, identified by the
first appearance of several high-fiber herbivores in the clade, along with numerous omnivorous taxa.
The discrete characters and continuous morphometric characters indicate the same disparity trends.
Therefore, we argue that in the absence of one of these two possible proxies, the disparity obtained
from just one source can be considered robust and representative of a general disparity pattern