There simply weren't any horned dinosaurs from that time period in North America; they all came later : 15million to 20million years later.
22.
These occipital condyles _ distinctive, spherical bones characteristic of ceratopsians _ were part of the ball joint that supported the horned dinosaur's weighty head.
23.
In 1888 and 1889, Othniel Charles Marsh described the first well preserved horned dinosaurs, " Ceratops " and " Triceratops ".
24.
Thomas Holtz would also note that " Tyrannosaurus " had proportionately longer feet than the animals it hunted : duck-billed dinosaurs and horned dinosaurs.
25.
When Das can't find them he goes searching and finds a herd of " Einiosaurus ", horned dinosaurs, grazing on the plains.
26.
That might explain the bonanza of horned dinosaur fossils in the tundra underneath the team members'feet _ possibly the densest concentration of saurian fossils in the world.
27.
Cope redescribed " Monoclonius " as a horned dinosaur, with a large nasal horn and two smaller horns over the eyes, and a large frill.
28.
They were replaced by duckbill dinosaurs, armored dinosaurs, horned dinosaurs and huge large, low-built plant eaters that seemed to have jaws better suited for chewing.
29.
Wolfe said the Turanoceratops, which had been believed to be the oldest horned dinosaur ever found, was several million years younger than the one he and his son discovered.
30.
The wraps come off Thursday as the Smithsonian's National Museum of Natural History returns the three-horned dinosaur to public display after more than two years being refurbished.
