Jaw Shapes of 90 Shark Species Show: Evolution Driven by Habitat
Published:06 Jun.2023    Source:University of Vienna

One of the most prominent traits in sharks is the shape of their lower jaws, which bear also impressive teeth. With their jaws, sharks are able to feed on a wide variety of prey, which also places them among the Ocean's top predators. The wide prey spectrum is also reflected in the corresponding adaptations that sharks have evolved through out their evolutionary history. All of these adaptations allow them to spread into virtually all marine habitats, with some species even venturing into freshwater.

To study the potential relationship between jaw morphology and the sharks' life style, an international and multidisciplinary research team, from the University of Vienna, Imperial College London (UK), Muséum national d'histoire naturelle (Paris, France), Christian-Albrechts-University (Kiel, Germany), and Naturalis Museum (Leiden, The Netherlands) conducted a quantitative analysis by using X-ray computed tomographic scans of the jaws of 90 shark species and preparing 3D reconstructions to estimate how jaw shape of sharks evolved through time.
The results illustrate the importance of prey, level in the marine webs and habitat in relation to jaw shape diversity among shark species. This also helps to uncover the evolutionary causes of the differences in jaw morphology related to habitats.