Semi-aquatic dinosaurs that roamed southern England 125 million years ago inherited the brainpower from their ancestors to catch the fish they lived on, according to new research.
Scientists from the University of Southampton and Ohio University have reconstructed the brains and inner ears of two spinosaurs, which they say helps reveal how these large predatory dinosaurs interacted with their environment.
Spinosaurs were adapted with long crocodile-like jaws and conical teeth to stalk river banks in search of prey, often large fish.
This way of life was a significant change from other theropods, such as allosaurus and tyrannosaurus.
Now the researchers have scanned the braincases of baryonyx fossils from Surrey and ceratosuchops from the Isle of Wight to better understand the evolution of spinosaur brains and senses – and the results have been published in the Journal of Anatomy.
A University of Southampton spokesman said: “The braincases of both specimens are well preserved, and the team digitally reconstructed the long-decayed internal soft tissues.
“The researchers found that the olfactory bulbs, which process smells, were not particularly developed, and the ear was probably connected to low-frequency sounds.
“Those parts of the brain involved in keeping the skull stable and the sight of prey may have been less developed than in the more specialized spinosaurs.”
Chris Barker, a PhD student at Southampton who led the study, said: “Despite their unusual ecology, the brains and senses of these early spinosaurs appear to have retained many features similar to other large theropods – there is no evidence that his half body. -aquatic lifestyles are reflected in the way their brains are organized.”
He explained that one interpretation of this evidence is that theropod ancestors already had brains and sensory adaptations suitable for part-time fish-catching, and that the spinosaurs only needed to develop their unusual snouts and teeth to become specialized. for semi-aquatic. there.
Contributing author Dr Darren Naish said: “Given that the skulls of all spinosaurs are so specialized for catching fish, it is surprising to see such a ‘non-specialised’ brain.
“But the results are still significant. It is exciting to learn so much about sensory abilities – hearing, smell, balance and so on – from British dinosaurs. Using cutting-edge technology, we obtained essentially all the brain-related information we could from these fossils.”