Dinosaur claws may have been used for digging and grasping
comments
The fearsome claws that once made up a dinosaur's killing repertoire may have evolved to have a much more mundane and everyday use.
Theropod dinosaurs - a group which includes the Tyrannosaurus Rex and velociraptor - are often regarded as carnivorous, predatory animals, using their sharp claws to capture prey.
But, a detailed analysis of the claws on the forelimbs of a unique group of these dinosaurs has revealed that the form and shape varied widely between species, suggesting they may have been used for digging and grasping.
A study from the University of Bristol has revealed that during their transition from carnivores to herbivores, therapod dinosaurs developed a large variety of claw shapes adapted to specific functions such as digging, grasping or piercing. This illustration shows the different shapes in the therizinosaur group of theropods
WHAT WERE THE THERIZINOSAURS?
Theropod dinosaurs - a group which includes the Tyrannosaurus Rex and velociraptor - are often regarded as carnivorous, predatory animals.
The name, for example, means 'beast footed'.
Therizinosaurs were an unusual group of theropods that lived between 145 and 66 million years ago.
They were large animals - up to 22ft (7 metres) tall with claws more than 19 inches (50 cm) long on their forelimbs.
They also had elongated necks and a coat of primitive, down-like feathers along their bodies.
Unlike their nearest relatives, however, the teeth and jaw morphology of therizinosaurs suggest they were herbivores.
Dr Stephan Lautenschlager from Bristol University's School of Earth Sciences studied the differences in claw shape to see how they are related to different functions.
His research, published in the journal Proceedings of the Royal Society B, focused on the therizinosaurs - an unusual group of theropods that lived between 145 and 66 million years ago.
Dr Lautenschlager said therizinosaurs were very large animals, up to 22ft (7 metres) tall, with claws more than 19 inches (50 cm) long on their forelimbs.
They also had elongated necks and a coat of primitive, down-like feathers along their bodies.
Unlike their nearest relatives, however, the teeth and jaw morphology of therizinosaurs suggest they were herbivores.
To fully understand how the different claws on the forelimbs were used, detailed computer models were created to simulate a variety of possible functions for different species and claw morphologies.
The dinosaur claws were also compared to the claws of modern-day mammals.
To understand how the different claws on the forelimbs were used, computer models were created to simulate a variety of possible functions. The claws were also compared to those of modern-day mammals. This is a fossil of the enlarged claws on the forelimbs of the Therizinosaurus cheloniformes
In the course of evolution, several theropod groups, including therizinosaurs, changed from being carnivores to become plant eaters.
The new study reveals that, during this transition, theropod dinosaurs developed a large variety of claw shapes adapted to specific functions, such as digging, grasping or piercing.
Dr Lautenschlager said: 'Theropod dinosaurs were all 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.'
'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.
'This suggests dietary adaptations were an important driver during the evolution of theropod dinosaurs and their transition to modern birds.'
The research also found the claws of the nothronychus theropod adapted specifically for digging.
Put the internet to work for you.
0 comments:
Post a Comment