Large theropods were as intelligent as reptiles, but not as smart as apes, according to a new study led by paleontologists at the University of Bristol.
tyrannosaurus rex Holotype specimen at the Carnegie Museum of Natural History in Pittsburgh, USA. Image credit: Scott Robert Anselmo / CC BY-SA 3.0.
in study Vanderbilt University paleontologist Suzana Herculano-Hausel announced last year that dinosaurs tyrannosaurus It had a huge number of neurons and was much more intelligent than expected.
She argued that these high numbers of neurons could directly inform intelligence, metabolism, and life history. tyrannosaurus In some habits they were more like monkeys.
Theropod dinosaurs of North America from the Late Cretaceous tyrannosaurus “It is an apex predator, one of the largest, heaviest, and most powerful (in terms of bite force) terrestrial carnivores ever known,” said Dr. Heidi George from the University of Bristol.
“Recently, Dr. Herculano Hausel proposed that we should add primate-level intelligence to great apes. tyrannosaurusAlready an impressive predation history, based on high estimates of the number of neurons in the forebrain. ”
“This conclusion arose from the paradigm that neurological variables inferred from endocasts can be used to infer metabolic parameters, behavior, and lifespan of fossil species.”
In the new study, Dr. George and his co-authors took a closer look at the techniques used to predict both brain size and number of neurons in dinosaur brains.
They found that previous assumptions about the size of dinosaur brains and the number of neurons they contained were unreliable.
This new study follows decades of analysis in which paleontologists and biologists studied the size and anatomy of dinosaur brains and used these data to infer behavior and lifestyle.
Information about dinosaur brains comes not only from the shape of the brain cavity itself, but also from its mineral fillings, called endocasts.
The authors found that their brain size, particularly the size of the forebrain, was overestimated, and thus the number of neurons was also overestimated.
Furthermore, we show that estimates of neuron number are not a reliable guide to intelligence.
“To reliably reconstruct the biology of a long-extinct species, researchers need to examine multiple lines of evidence, including skeletal anatomy, bone histology, the behavior of living relatives, and trace fossils.” the researchers said.
“To determine the intelligence of dinosaurs and other extinct animals, it's best to use a wealth of evidence, from gross anatomy to fossilized footprints, rather than relying solely on estimates of neuron counts,” Dr. Heidi said. added.
“We argue that it is not a good idea to predict the intelligence of extinct species when only the number of neurons reconstructed from endocasts is sufficient,” said Dr. Kai Kasper, a paleontologist at Heinrich Heine University. Ta.
“Neuron number is not a good predictor of cognitive ability, and using neuron number to predict intelligence in long-extinct species can lead to very misleading interpretations,” Mikel Crusafont Catalan Paleontologist said Dr. Ornella Bertrand, a paleontologist at the Institute.
“The possibility is that tyrannosaurus The possibility that they were as intelligent as baboons is both fascinating and frightening, and has the potential to transform the way we view our past,” said Dr Darren Naish, a palaeontologist at the University of Southampton. .
“But our study shows how all the data we have contradicts this idea. They were more like smart giant crocodiles, which was just as fascinating. ”
of result Published in anatomical records.
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Kai R. Kasper other.How clever! tyrannosaurus• Examine claims about the extraordinary cognitive abilities of dinosaurs and the application of neuron number estimation in paleontological research. anatomical records, published online on April 26, 2024. doi: 10.1002/ar.25459
Source: www.sci.news
