Benjamin Faulkner

My research identifies skeletal adaptations that distinguish plant-eating lizards from meat-eaters beyond just teeth and jaws. By analyzing body proportions across 95 specimens from 20 families, I’ve discovered that herbivorous lizards have proportionally larger skeletal hip dimensions and trunk volumes to accommodate their specialized digestive systems. This provides paleontologists with a new method to identify herbivores in the reptile fossil record when evidence from the head is incomplete or ambiguous.

Herbivory has evolved multiple times in reptiles, but identifying plant-eaters in the fossil record traditionally relies on teeth and jaws, which can be ambiguous, fragmented, or missing entirely. My research uses a present-to-past approach, investigating whether living herbivorous lizards have skeletal adaptations beyond the skull that could provide reliable indicators of diet type in fossils. I measured 13 skeletal features from 95 lizard specimens across 20 families and applied multivariate statistical analyses to determine how body shape correlates with diet. Results revealed that herbivorous lizards have proportionally larger hip and trunk dimensions relative to their head size compared to carnivores, reflecting the room needed for their enlarged digestive systems, which are required to process fibrous plant material. Statistical models using these measurements correctly identified diet types with 85% accuracy, with body measurements performing as well as head measurements when used independently. This supports the “”accommodation space hypothesis”” – that herbivores’ specialized digestive systems are reflected in the skeleton as measurable proportional differences. This work provides paleontologists with additional tools to better understand when and how many times plant-eating evolved throughout reptile history.