Since the 1970s, scientists generally held the belief that Tyrannosaurus rex (T. rex) boasted intelligence on par with modern reptiles. However, a 2023 study from a Brazilian neuroscientist stirred controversy, suggesting that T. rex might have possessed cognitive abilities closer to those of primates. This notion raised questions: Could this fearsome dinosaur have been as intelligent as a baboon or even a human?
However, a recent study published in The Anatomical Record offers a different perspective. Led by zoologist Kai Caspar from Heinrich Heine University Düsseldorf in Germany, an international team of scientists revisited the topic. Their findings align more closely with the traditional view, suggesting that T. rex’s intelligence was akin to that of a crocodile rather than a primate.
The study addressed two main issues with the 2023 research. Firstly, it pointed out that the earlier study overestimated T. rex’s brain size by assuming that the brain filled the entire cranial cavity. This assumption, the researchers argue, doesn’t align with the available data on dinosaur endocasts. Secondly, the 2023 study included inconsistent data, mixing samples from both juvenile and adult T. rex individuals.
To refine their analysis, Caspar and his team standardized body mass estimates and excluded structures within the T. rex skull that aren’t directly involved in neural activity. Despite their efforts, they couldn’t replicate the findings of the 2023 study. Instead, their estimates suggested that T. rex likely had a similar number of neurons to crocodiles, rather than the higher count proposed by the Brazilian study.
However, the study emphasizes that brain size and neuron count alone aren’t reliable indicators of cognitive intelligence. As seen in modern animals, such as pigeons, intelligence can vary widely regardless of brain size or neuron count.
Caspar emphasizes that attributing T. rex’s intelligence to that of a crocodile doesn’t diminish its fascinating nature. Understanding more about T. rex’s brain biology can provide insights into the behaviors of both extinct dinosaurs and modern reptiles, contributing to our broader understanding of evolutionary history. Ultimately, while T. rex may not have possessed primate-level intelligence, it remains a captivating subject of study, shedding light on the diverse world of prehistoric life.
