Jan 11, 2023 I Paul Seaburn

Are You Smarter Than a T. Rex? Maybe Not!

Most Hollywood movies depicting a Tyrannosaurus rex, especially the Jurassic Park series, do the Tyrant Lizard King no favors when it comes to depicting their intellectual abilities. Running, stomping, eating and scaring seem to be their only skills and, despite having the largest brains among the cast members, they never seem to be able to think their way out of problem situations. A new study may force a rewrite of the next script – researchers extrapolating bird brains, the T. rex’s closest modern relative, found that the giant lizards had more than enough brain neurons to think at a level where they would have been able to solve problems, create and use tools, even engage in cultural and social behaviors similar to modern birds … some of whom are pretty smart and social themselves.

“What if the asteroid hadn’t happened? That’s a whole other world that would have been terrifying.”

Yeah ... what if?

Suzana Herculano-Houzel, a neuroscientist and biologist at Vanderbilt University, is the author of the paper ”Therapod dinosaurs had primate-like numbers of telencephalic neurons,” published in the Journal of Comparative Neurology. She tells The Daily Mail her unusual idea was inspired by anti-apocalyptic thoughts – what if the asteroid-induced Cretaceous–Paleogene extinction event had not wiped out nearly all of the dinosaurs 66 million years ago? At that time, therapods were the apex predators and the T. rex was the apex of the apexes. Herculano-Houzel suspected that sheer size was not the only reason for its top position – this huge beast had to have some intelligence too. Unfortunately, there is no T. rex brain matter to study, so Herculano-Houzel turned to the modern but smaller T. rexes – birds.

“Birds have (tiny) neurons galore in their brains and cognition to match”

Suzana Herculano-Houzel is a Brazilian-born neuroscientist currently working as an Associate Professor at Vanderbilt University, where her lab investigates the extent and limitations of brain diversity, how brain diversity arose in evolution, and what difference it makes that brains are different. She starts her study with the fact that modern science has determined that the slang expression “bird-brained” to mean “not too intelligent” has been proven wrong – modern birds have been shown to have densely packed neurons in the tiny brains in their tiny skulls. Some can speak, some can use tools, some can even solve problems and many continue to impress us with their migration and homing abilities. In other words, “bird-brained” should be a compliment. Herculano-Houzel was also aware that paleontologists have determined that there is a strong evolutionary link modern birds of all sizes and the T. rex, velociraptors and other therapod dinosaurs – some of which were developing bird like characteristics before their lives were so rudely interrupted by that giant space rock hitting the Gulf of Mexico. What we don’t know is how much of their brain characteristics they shared. Herculano-Houzel had an idea.

“First, you have to have good reason to believe that the same proportionality that applies to birds already applied to dinosaurs like T. rex, which is what I just did.”

 She used a technique called phylogenetic bracketing, which uses the evolutionary tree to  predict the likelihood of unknown traits in extinct organisms and creatures. However, this wasn’t ordinary phylogenetic bracketing – while today’s largest birds like the ostrich and emu are huge in comparison to hummingbirds, they are the hummingbirds in comparison to T. rex. Moreover, their walnut-sized brains pale in comparison to the barrel-sized heads of T. rex. Would the T. rex be proportionally as smart as an ostrich? Or smarter?

In the paper, Herculano-Houzel explains that theropods were much different than other dinosaurs of their time. In particular, they had similar brain sizes to those you might expect to find in a bird of the same size. Knowing how many neurons are in the brain of an ostrich, she then estimated ho many there would be in the brain of a T. rex. That number is 3 billion neurons. Unless you are a neuroscientist, that doesn’t mean much, so Herculano-Houzel put it in perspective in a tweet.

“It's officially news: T. rex had baboon-like numbers of brain neurons, which means it had what it takes to build tools, solve problems, and live up to 40 years, enough to build a culture!” (@suzanahh)

Herculano-Houzel brings another perspective into the equation – age. T. rexes reached up to 40 years of age. If they had the brain power of a baboon and lived that long, they had plenty of time to do a lot of learning, experimenting, testing and failing in physical, mental and social activities. At the baboon level of intelligence, these giant predators could still be smart enough to form bonds with each other and develop a group relationship.

“If they were hunters, maybe you find evidence of them hunting in groups, using some sort of social communication. If you have no reason to expect that, you’re not going to look for that evidence.”

Social? Really?

With the intelligence of a baboon, which are not as smart as the top-level chimpanzees but still one of the smarter non-human primates, T. rex could have done so much more than is depicted in movies and books. Similarly, another large carnivorous dinosaur, the Alioramus, had over 1 billion, which would put its brain capacity at the level of a capuchin monkey – another small but smart primate. Herculano-Houzel also notes that a baboon-like T. rex could easily pass its knowledge down through generations. She gives another comparison – this time, to a different primate that has taken over entire cities in India.

“An elephant-sized but agile carnivoran biped endowed with macaque- or baboon-like cognition must have been an extremely competent predator indeed.”

And, had they not been wiped out in the Cretaceous–Paleogene extinction event, they could still be alive today – think of alligators, snapping turtles and other survivors – and taking over cities like macaque monkeys … begging for cow carcasses for food, blocking highways, defecating everywhere. Perhaps it was to our benefit that the T. rex was smart … but not smart enough.

Jurassic Park still owes them an apology.

Paul Seaburn

Paul Seaburn is the editor at Mysterious Universe and its most prolific writer. He’s written for TV shows such as "The Tonight Show", "Politically Incorrect" and an award-winning children’s program. He's been published in “The New York Times" and "Huffington Post” and has co-authored numerous collections of trivia, puzzles and humor. His “What in the World!” podcast is a fun look at the latest weird and paranormal news, strange sports stories and odd trivia. Paul likes to add a bit of humor to each MU post he crafts. After all, the mysterious doesn't always have to be serious.

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