Data from: Elevated evolutionary rates of biting biomechanics reveal patterns of extraordinary cranio-dental adaptations in some herbivorous dinosaurs

Adaptation to specialist ecologies is a key innovation that has
contributed to the evolutionary success of many vertebrate clades,
underpinning the acquisition of diverse skull morphologies. Dinosaurs,
which dominated Mesozoic terrestrial faunas, acquired herbivory multiple
times, including in clades historically regarded as predominantly
carnivorous. The evolution of herbivory in theropod dinosaurs is linked to
drastic changes in dental and craniomandibular functional morphology, yet
whether such changes occurred more rapidly in herbivorous lineages
compared to in carnivorous lineages remains untested in a phylogenetic
framework. Here, we infer rates of phenotypic evolution in relative biting
edge lengths to test the hypothesis that the acquisition of herbivory is
associated with rapid changes in jaw biomechanics. We find elevated rates
of biomechanical evolution in theropods with foreshortened and beaked
skulls (Oviraptorosauria, Limusaurus), as well as in ceratopsians and
Diplodocus. A reduced biting edge length and increased jaw efficiency
unites these high-rate lineages, indicating selection for greater
efficiency in biting biomechanics. Additionally, we hypothesise that
extreme ontogenetic changes within species' lifetimes may be behind
some instances of branch-wise elevated rates. Thus, we show how
exceptional rates of biomechanical evolution can reveal signatures of
adaptations within dinosaur lineages and potentially along ontogenetic
sequences.