This dino’s headgear likely impressed a mate.

Two elephant-size dinosaurs face each other, showing off their long horns and bony neck frills. They’re both strong, fully grown Triceratops, and neither backs down. Suddenly, the two lurch forward and lock horns, pushing against each other like deer clashing antlers. One loses ground and walks away, defeated. The winner has impressed a nearby female Triceratops.

Dressed to impress

Although it might appear dangerous, Triceratops was actually a slow-moving herbivore that used its beak-like jaw and slicing teeth to pluck and chew tough plants that other dinosaurs couldn’t eat. It roamed in what’s now western North America during the Cretaceous period, about 69 million years ago.

Its name comes from the Greek words meaning “three-horned face” because of the two horns on its brow and smaller horn above its mouth. The size and shape of the horns changed so much as the dinosaur aged that scientists first thought fossils of young and old Triceratops were two different species. (Some adult Triceratops skulls are 10 feet long!)

Paleontologists are still gathering evidence to learn why Triceratops had those big horns and frills. But because both males and females had them, experts think that the dinos might’ve used the giant body parts to impress each other. (That’s not always the case: Female Indian peafowl, for example, are brown while the males, called peacocks, have a spectacular fan of colored feathers.) Because both of the partners were trying to impress each other, it might mean that these animals shared some parenting duties.

Most-found fossil  

This dino lived alongside Tyrannosaurus rex, but both species—and all the other non-avian dinosaurs (meaning dinos that weren’t birds)—went extinct when an asteroid hit Earth 66 million years ago. Today, Triceratops is one of the most-found fossils, which is good news for dino lovers: It means scientists can use new technology to examine lots of fossils and find new answers about these animals.

Watch Dino Road Trip

Ali and Sean travel back 66 million years to get a look at the most famous dinosaur of all time—the Tyrannosaurus Rex! Tour guide Simon reveals that the T. rex may be related to … a chicken? Find out if Simon is for real—or for the birds.