The structure, composition, and shape of teeth have been related to dietary specialization in many vertebrate species, but comparative studies on snakes’ teeth are lacking. Yet, snakes have diverse dietary habits that may impact the shape of their teeth. We hypothesize that prey properties, such as hardness and shape, as well as feeding behavior, such as aquatic or arboreal predation, or holding vigorous prey, impose constraints on the evolution of tooth shape in snakes. We compared the morphology of the dentary teeth of 63 species that cover the phylogenetic and dietary diversity of snakes, using 3D geometric morphometrics and linear measurements. Our results show that prey hardness, foraging substrate, and the main foraging mechanical challenge are important drivers of tooth shape, size, and curvature. Overall, long, slender, curved teeth with a thin layer of hard tissue are observed in species that need to maintain a grip on their prey.  Short, stout, less curved teeth are associated with species that undergo high or repeated loads. Our study demonstrates the diversity of tooth morphology in snakes and the need to investigate its underlying functional implications to better understand the evolution of teeth in vertebrates.

We microCT scanned the dentary teeth of 63 species of snakes using a Phoenix Nanotom S μCT‐scanner (General Electric, Fairfield, CT, USA). The 3D reconstruction was done using Phoenix datos|x2 (v2.3.0, General Electric, Fairfield, CT, USA) and the subsequent segmentation was performed using VGStudioMax (v1.0, Volume Graphics GmbH, Heidelberg, Germany). We then compare the shape of these teeth using 3D geometric morphometrics. We used phylogenetic comparative analysis to investigate the relationship between shape and diet. We provide the R code, Rdata, and all necessary files to reproduce our results.

We also added the supplementary material related to our publication.

R, Meshlab, MorphoDig