A new study has found that dinosaur claw shapes evolved to adapt to the species' changing dietary needs.
Dr. Stephan Lautenschlager, lead author of the study from Bristol's School of Earth Sciences, and his colleagues stated that these animals shifted from being carnivores to herbivores. The analysts studied the dinosaur group known as the therizinosaurus, which lived around 145 and 66 million years ago - these were huge animals that grew up to 7 meter tall, had long necks, claws longer than their forelimbs, and down-like feathers on their bodies. They found that a group of dinosaurs called therapods, which included species such as the Tyrannosaurus Rex and Velociraptor, have highly variant claw form and function.
"Theropod dinosaurs are bipedal, which means their forelimbs were no longer involved in walking as in other dinosaurs. This allowed them to develop a whole new suite of claw shapes adapted to different functions," Dr. Lautenschlager said in a press release.
To see how the different claws and forelimbs were utilized, researchers made computer models that simulated different situations and went through different species and claw morphologies. The dinosaur claws were also studied side by side with today's existing mammals, whose claws are known for particular uses.
A number of theropod groups, which included the therinozaurs, went from being carnivores to herbivores during evolution. The study showed how the claws of these dinosaurs changed to do a variety of things, such as grasping, digging, and piercing.
"It's fascinating to see that, with the shift from a carnivorous to a plant-based diet, we find a large variety of claw shapes adapted to different functions," Dr. Lautenschlager added. "This suggests that dietary adaptations were an important driver during the evolution of therapod dinosaurs and their transition to modern birds."
Further details of this study can be read in the journal, Proceedings of the Royal Society B.
