According to new research, the jaws of theropod dinosaurs evolved over time to be stronger, which allowed them to eat more difficult foods.
The University of Birmingham’s team was able, using digital modeling and computer simulations. They were also able map the changes made in fossil records.
They uncovered a common trend of jaw strengthening in theropods – dinosaurs known for their hollow bones and three-toed limbs – as well as an upturned jaw in carnivore theropods, and a downturned jaw in herbivores.
These improvements over many millions of years have made their jaws stronger when they are biting. This reduces the chance of breaking bones from harder foods.
A life reconstruction of the Late Cretaceous Iren Dabasu Formation fauna showing different diets for theropod dinosaurs. These dietary niche partitionings may have helped to diversify theropod dinosaurs, eventually leading to modern bird evolution.
They created computer models that included over 40 lower jaws for five species from theropod dinosaur families.
These included carnivores like Tyrannosaurus and Velociraptor, and lesser-known herbivores like ornithomimosaurs, therizinosaurs and oviraptorosaurs.
Fion Waisum Ma was the PhD researcher behind this research. She said that while theropod dinosaurs have been commonly depicted as prey in popular culture they actually are much more varied.
“It is fascinating to observe the jaws becoming more structurally strong over time in both carnivores (and herbivores),” she stated.
This gives them the ability to use a larger variety of food products.
Theropod dinosaurs experienced extreme diet changes over their evolutionary history, which spanned 165 millions years.
They started out as carnivores. Later, they evolved into more specialist carnivores.
“Studying the changes in their eating habits can help us understand how we might transition to other vertebrate foods.”
This team provided an example showing how it changed over time.
Guanlong, an early carnivore like Tyrannosauroids had a very straight and slender jaw.
Tarbosaurus’s and Tyrannosaurus’s later forms developed deeper jaws. The front part bent up, increasing jaw strength.
Team explained that the strength of the jaw is crucial in the evolution herbivorous dinosaurs. This was due to repetitive plant cropping stress.
Caudipteryx and Erlikosaurus, herbivores, have jaws that bend in a downward direction. This could be helpful to relieve stress.
“It’s fascinating to observe how theropod dinosaurs have evolved various strategies to increase jaw strength depending on what they eat,” said Dr Stephan Lautenschlager (Senior Lecturer, University of Birmingham) and the senior author of this study.
A new study claims that the jaws developed from dinosaur jaws to grow stronger over time.
A team of researchers from Birmingham, England used digital modeling and computer simulations to create a map of changes in the fossil record.
Researchers discovered a pattern of jaw strengthening among theropods. These dinosaurs were known for their hollow bones, three-toed limbs and three-toed feet.
‘This was achieved through bone remodelling – a mechanism where bone is deposited in regions of the jaw that experience high stresses during feeding.’
Dr Lautenschlager added: “The similarity in jaw strengthening through time and growth suggests that developmental patterns of juvenile dinosaurs ultimately affected evolution.
“This probably facilitated jaw evolution and the overall success of theropod dinosaurs for more than 150 million years.”
The findings have been published in the journal Current Biology.