Brett Smith for redOrbit.com – Your Universe Online
Sauropod dinosaurs, like Diplodocus and Brachiosaurus, were the largest land animals to ever walk the Earth and many of these massive creatures lived alongside each other in close proximity.
These enormous herbivores developed feeding adaptations unique to their particular species which permitted them to divvy up the available plant life in an area they might have to share, according to new research from British scientists at The Natural History Museum in London and University of Bristol.
Published in Proceedings of the Royal Society B, the new study also looked at how these animals could get enough sustenance into their bodies, considering they had such small heads and mouths.
In their investigation, researchers used CT tests to digitally build up the skulls of Camarasaurus and Diplodocus, together with the jaw and neck muscles of both species based on evidence left on the bones.
Image Above: The completed skull model of the Late Jurassic North American sauropod dinosaur, Camarasaurus. Credit: David Button
From this information, a biomechanical computer modeled the skull of Camarasaurus using Finite Element Analysis (FEA), a process often used in engineering and design to determine stress and pressure distribution across complicated shapes. This model was then compared to a pre-existing model of Diplodocus in order to examine how the dinosaurs ate.
“Our results show that although neither could chew, the skulls of both dinosaurs were sophisticated cropping tools,” said study author David Button, a sauropod expert at the University of Bristol. “Camarasaurus had a robust skull and strong bite, which would have allowed it to feed on tough leaves and branches. Meanwhile, the weaker bite and more delicate skull of Diplodocus would have restricted it to softer foods like ferns.”
“However, Diplodocus could also have used its strong neck muscles to help it detach plant material through movements of the head,” Button added. “This indicates differences in diet between the two dinosaurs, which would have allowed them to coexist.”
The study team also used biomechanical information from other sauropod species to determine the functional differences in their skulls and jaws. They discovered that other sauropods were also highly diverse in feeding adaptations, indicating a wide range of diets.
“In modern animal communities differences in diet such as this – termed ‘dietary niche partitioning’ – allow multiple similar species to coexist by reducing competition for food,” explained study author Emily Rayfield, a professor of paleobiology at Bristol. “This is the first study to provide strong, numerical, biomechanical evidence for (this phenomenon) in a fossil community.”
The study also aids in explaining the development of sauropod feeding methods and how these enormous creatures ate enough food to sustain their size. While earlier sauropods might have been able to consume a wide range of plants, evidence from later lineages indicates that the parallel evolution of traits led to more specialized feeding behaviors.
“Our study provides insight not only into the ecology of dinosaurs but more generally into the mechanisms supporting species-richness in other animal communities, both from the fossil record and in the present-day,” said study author Paul Barrett, a vertebrate and anthropology paleobiologist at The Natural History Museum.