The focus of the study by Dr Stephan Lautenschlager and Dr Emily Rayfield of the University of Bristol with Dr Perle Altangerel (National University of Ulaanbaatar) and Professor Lawrence Witmer (Ohio University) was the skull of Erlikosaurus andrewsi, a 3-4m (10-13ft) large herbivorous dinosaur called a therizinosaur, which lived more than 90 million years ago during the Cretaceous Period in what is now Mongolia, and which shows evidence that part of its snout was covered by a keratinous beak.
This new study reveals that keratinous beaks played an important role in stabilizing the skeletal structure during feeding, making the skull less susceptible to bending and deformation.
Lead author Lautenschlager of Bristol's School of Earth Sciences said that it has classically been assumed that beaks evolved to replace teeth and thus save weight, as a requirement for the evolution of flight.
He said that their results indicated that keratin beaks were in fact beneficial to enhance the stability of the skull during biting and feeding.
Co-author Dr Emily Rayfield, Reader of Palaeobiology at Bristol said that by using Finite Element Analysis, a computer modelling technique routinely used in engineering, they were able to deduce very accurately how bite and muscle forces affected the skull of Erlikosaurus during the feeding process.
She said that this further allowed them to identify the importance of soft-tissue structures, like the keratinous beak, which are normally not preserved in fossils.
Co-author Lawrence Witmer, Chang Professor of Paleontology at the Ohio University Heritage College of Osteopathic Medicine said that beaks evolved several times during the transitions from dinosaurs to modern birds, usually accompanied by the partial or complete loss of teeth and their study showed that keratin-covered beaks represented a functional innovation during dinosaur evolution.
--ANI (Posted on 03-12-2013)