Tyrannosaurus Rex as Smart as Crocodile, Not Primates or Humans: Study

A recent study has put to rest the notion that Tyrannosaurus rex was as brainy as a primate. For decades, scientists have likened the intelligence of T. rex to that of modern reptiles, like crocodiles. But a 2023 study sparked controversy by suggesting T. rex might have been closer in smarts to baboons or even humans.

However, a new study, published in The Anatomical Record has swung the pendulum back to the traditional view. Led by zoologist Kai Caspar from Heinrich Heine University Düsseldorf, the research team found that T. rex likely had a cognitive capacity more akin to crocodiles than primates.

The study addressed two main issues with the 2023 research. Firstly, it pointed out that previous estimates overestimated T. rex's brain size by assuming it filled the entire cranial cavity. Secondly, it highlighted inconsistencies in the data, including the inclusion of non-brain structures in brain size estimates and the use of samples from both juvenile and adult T. rex specimens.

By tidying up the dataset and excluding non-neural structures, the researchers arrived at different conclusions. Their estimates suggested that T. rex had between 250 million and 1.7 billion neurons, similar to counts in crocodiles. This starkly contrasts with the 2023 study, which proposed a neuron count closer to that of baboons.

However, the study cautioned against equating brain size and neuron count with intelligence. Neuron counts have shown to be unreliable predictors of cognitive ability across species. For instance, pigeons, despite their small brains, exhibit cognitive abilities comparable to monkeys with larger brains.

Despite the downgrade in intelligence from primate-level to crocodile-level, Caspar emphasized that understanding T. rex's brain biology can still offer valuable insights. It can shed light on the behaviors of both extinct dinosaurs and modern reptiles, enriching our understanding of evolutionary history. T. rex might not have been the brainiac we once thought, but its cognitive abilities still hold significant scientific intrigue.