Dinosaurs died out around 65 million years ago, likely wiped out by a huge comet or asteroid. But we can look at the fossil evidence they left behind to understand what these prehistoric beasts were really like. If you’re still relying on what you learned in grade school, and saw in Hollywood classics like Jurassic Park you’ve got dinosaurs all wrong. The scientific understanding of dinosaurs, and dinosaur behavior, has changed drastically even in recent years.
In ancient times, fossilized dinosaur bones were thought to have belonged to monsters, giants, or even dragons. In the 1800s, scientists realized that the teeth and bones were unlike those of any living animal so they must have been the remains of long-extinct creatures. And so, British paleontologist Sir Richard Owen coined the word “dinosaur” to describe these prehistoric creatures. But the fossil record can be hard to interpret, which brings me to those myths:
Dinosaurs were dumb: In the 1970s, a system was developed to estimate dinosaur intelligence based on the dinosaur’s brain weight relative to the brain weight of another living animal. It turns out that, based on that system, some dinosaurs (like the Velociraptor) were pretty smart.
Brontosaurus was the biggest dinosaur of all: Like me, you may have been taught that one of the biggest dinosaurs was the enormous plant-eater called Brontosaurus. But there’s one problem, that guy never even existed. Brontosaurus was invented when 19th century paleontologist O.C. Marsh misidentified an Apatosaurus skeleton as belonging to a new species. Even though the mistake was discovered in 1903, it wasn’t until the 1970s when museums got around to fixing their skeleton displays. Still, the long-necked dinosaurs were the largest.
Dinosaurs were covered in scales: You may have heard that some dinosaurs sported feathers. Fossil evidence now suggests that most or even all of them did. Researchers recently found fossils belonging to a small, two-legged dinosaur with scales and feather-like structures, dating back around 160 million years. This leads scientists to think that dinosaurs’ plumes may have evolved much earlier in dinosaur history than previously thought.
Dinosaurs were cold blooded: At first scientists thought dinosaurs were cold-blooded like reptiles. Then some researchers said that dinosaurs may have been warm-blooded. But based ondinosaurs’ growth rate, size, and metabolism, some scientists now pose that dinosaurs were mesotherms, which means they couldn’t control their body temperature as us mammals do, but they weren’t so dependent on their environments as cold-blooded reptiles are. They were somewhere in between.
Dinosaurs were slow movers: Dinosaurs may have been much speedier than you probably thought. Computer simulations suggest that this tiny guy was the fastest dinosaur of all, with a running speed of around 40 mph. Meanwhile, a six-ton T. rex could reach a top speed of around 18 mph. That’s one guy I’m glad I’ll never have to outrun.