While we don't like to talk ill of the dead, new physiological analysis has found that the king of the dinosaurs was not so smart after all. It upends previous research that last year likened the brain and neuronal composition of the Tyrannosaurus rex to that of a primate.
It's been a rough year or two for the long extinct dinosaur. First, we questioned their teeth, finding that those iconic chompers could very much have been smaller and hidden behind lips, and now an international team of paleontologists, behavioral scientists and neurologists have concluded that the T. rex wasn't smarter than your average lizard or crocodile. Why all the hate, science?
The new study kicks dirt in the face of the 2023 findings that the dinosaur's neuron count was a direct indication of its intelligence. It proposed that this would indicate high cognitive skills that could be backed up by evidence of 'evolved' cognitive skills such as tool use. But when the scientists replicated the previous study's method, the results told a very different story.
“The possibility that T. rex might have been as intelligent as a baboon is fascinating and terrifying, with the potential to reinvent our view of the past”, said Darren Naish, a paleontologist from the University of Southampton. “But our study shows how all the data we have is against this idea. They were more like smart giant crocodiles, and that’s just as fascinating.”
If you ask us, "smart giant crocodile" is possibly more terrifying than a monkey with a big ol' pink bum that matches its face.
How the team got to this dino diss involved looking at a bigger picture of physiology – skeletal anatomy, bone histology, trace fossils and the kinds of behaviors their modern-day relatives possess. This was paired with existing data on dinosaur brain size and shape.
When the researchers looked at endocasts of T. rex brains – internal modeling of the cranial vault where the dinosaurs' soft tissue would have once been housed – they found that previous brain-size estimates had been inflated, particularly around the all-important forebrain. This, the team argues, is a result of not taking into account the fact that dinosaurs, as reptiles, would most likely have had a lot of cerebrospinal fluid in their cranial vault, so a model of the brain filling that entire cavity is misleading.
Sadly, for the T. rex, the team says the neuron count estimates were too high, also. Neuron count also correlates with body size – the bigger you are as a species, the more you're likely to have – but when looked at in context with all of the other information, the dinosaur's cognitive abilities appeared to be more in the crocodile range.
“Neuron counts are not good predictors of cognitive performance, and using them to predict intelligence in long-extinct species can lead to highly misleading interpretations,” said Ornella Bertrand from the Miquel Crusafont Catalan Institute of Palaeontology.
“Determining the intelligence of dinosaurs and other extinct animals is best done using many lines of evidence ranging from gross anatomy to fossil footprints instead of relying on neuron number estimates alone,” said Hady George from the School of Earth Sciences at Bristol University.
So where does that leave the T. rex? There are worse things to be called than a reasonably smart lizard. After all, intelligence isn't everything. We bet these legendary therapods had other skills, such as giving really good massages and high-fives. Oh, wait...
The research was published in The Anatomical Record.
Source: University of Bristol
