Triceratops, with its three-horned face and huge rhino-like body, is probably the most well-known ceratopsian. But there are dozens of kinds of ceratopsians: some big, some small, some with long, spiky horns, and some with none. They all have a parrot-like beak, though!
The earliest known ceratopsian, Yinlong downsi (YIN-long-DOWN-see), doesn’t look much like Triceratops. It was less than four feet long from nose to tail and probably weighed around 33 pounds— about the same as a medium-sized dog. It also didn’t have horns or frills, and it spent most of its time walking on two legs instead of four.
Psittacosaurus (sih-TOK-uh-SAR-us) was another small, hornless ceratopsian that walked on two legs, but it was more closely related to Triceratops than to Yinlong. Many Psittacosaurus remains have been found in groups, suggesting the animals were social. Its most notable feature was the six-inch-long quill-like bristles on its back and tail!
Styracosaurus (stih-RAK-uh-SAR-us) means “spiked lizard,” and it’s certainly earned its name—look at all those horns! It had a two-foot long horn on its nose, a horn on each cheek, and four to six more horns on its frill. Scientists have found bones of large groups of Styracosaurus, hinting that these animals, along with other ceratopsians, might have lived in herds.