Dinosaurs ruled the Earth for more than 150 million years. Some were longer than semi trucks. Others were smaller than chickens. Some ate meat. Others ate plants. But all dinosaurs were the same in some important ways.

All dinosaurs were reptiles. They all laid eggs. And they all had claws and tails. Let’s take a closer look at the body of one dinosaur: the enormous Patagotitan (pat-uh-goh-TYE-tun).

Dinosaur tails were long and strong.

Most dinosaurs had skin covered in tough scales.

Wow, we’re really old.

That’s funny. I don’t feel a day over a hundred million!

Patagotitan weighed as much as 12 African elephants. It may have been the largest land animal ever!

Almost all dinosaurs—especially the huge ones—had really small brains.

Dino Legs

Dinosaurs’ back legs went straight down from their bodies, like a bird’s legs—or YOUR legs!

Other reptiles have legs that go out to the sides.

Dinosaur claws were made of the same stuff as your fingernails and hair.