Research sheds new light on dinosaur hunting techniques
First, palaeontologists dared to suggest that T. rex wasn't the fearsome predator portrayed by the media. Now, new research suggests that the smaller carnivorous dinosaurs weren't as vicious as previously thought either.
Scientists at the University of Manchester and the Natural History Museum carried out a study into the workings of the enormous foot claw found on the small meat-eating dinosaurs Velociraptor (of Jurassic Park infamy) and Deinonychus, both belonging to a group called dromaeosaurs. The study has found that instead of slicing through flesh and disembowelling prey, as previously thought, the dinosaur primarily used its foot claw as a tool to hold on to and perhaps clamber over its victims.
'The alleged disembowelling claws of Velociraptor and its close relatives have long captured the imagination of both science and the media.' Said Dr Phil Manning of the University of Manchester (The Manchester Museum). 'Disarming such a legendary dinosaur is in many ways a great pity, but hopefully it will help us understand more about this enigmatic group's hunting technique and predatory abilities.'
The results of this experiment were first shown on The Truth about Killer Dinosaurs, a BBC television production. A team from Pennicott Payne Models and Special Effects produced a scientifically accurate robotic limb, based on detailed measurements from dromaeosaur fossil remains and information on limb function in living animals, to test the disembowelling theory. Information on the shape and composition of the claw was gleaned from a study of living birds and reptiles.
The robotic limb was used to mimic a strong kicking motion and its damaging effect was tested (at high and low speed) by impacting it into the flesh of pig and crocodile carcasses. Instead of producing the expected large slashing wound, only small, rounded puncture holes where produced. Moreover, the curvature of the claw was found to cause flesh around the wound to bunch together, preventing the claw from falling out. Scientists also discovered that the depth of the wound was not substantial enough to pose a danger to a large herbivorous dinosaur (such as the contemporary Tenontosaurus), but would have been fatal to smaller prey.
This new research suggests that instead of using their claws for slashing, these dinosaurs may have used them for climbing. Research into the curvature of the claw has shown that it could have been used for gripping onto the flanks of live prey. The dromaeosaur's sharp serrated teeth would then tear into the flesh of its prey whilst clinging tightly to its victim. There are some similarities between this and the hunting techniques of modern day big cats, which use their protracted claws to cling onto their prey as their powerful jaws deliver the killer blow.
"This work disproves a long-standing idea about Velociraptor and its relatives and sheds light on an entirely novel way of life in these animals", said Dr Paul Barrett of the Natural History Museum.
Notes for editors
This research is published in Biology Letters, online at: http://www.journals.royalsoc.ac.uk/