Скачать или смотреть What Did Dinosaurs Eat?

Paleontologists have long inferred the diets of extinct dinosaurs based on the shape of the teeth. Most dinosaurs with sharp, bladed and serrated teeth, like steak knives, belong to the group of dinosaurs called theropods, such as Tyrannosaurus, Allosaurus, and Velociraptor, and most likely used their teeth to slash prey and slice meat. Other dinosaurs possessing sets of teeth that wore down into flat grinding surfaces as the animal chewed, such as Triceratops and duckbills, most likely used their teeth to grind or shred leaves, seeds, and other vegetation.

One can also look at the position of the jaw joint to get a general sense of an animal's diet. If the joint between the upper and lower jaws is at the same level as the tooth rows, as in modern cats and other carnivores, the animal was probably a meat-eater whose jaw muscles allowed the jaws to close with tremendous speed and precision, as was likely the case with Tyrannosaurus. However, if the jaw joint was lower than the tooth rows, such as in modern herbivores, the jaw muscles allowed the teeth in the upper and lower jaws to move back-and-forth or side-to-side across each other to grind or slice vegetation, as was likely the case in Triceratops and duckbills.

Although it's often impossible to determine exactly what a specific kind of dinosaur ate, certain fossils occasionally provide clues. Some "mummified" duckbills preserve fossilized stomach contents in the ribcage, including conifer needles, twigs, seeds, and fruits. Some AMNH Coelophysis skeletons at reveal the bones of small crocodiles inside the ribcage that probably represent the animal's last meal. Also, coprolites (fossilized feces) can also provide clues to diet. Bone fragments in one coprolite associated with a skeleton of a Velociraptor-like dinosaur from Mongolia shows that it was eating small, lizard-sized animals.

This video is part of a series, "Dinosaurs Explained," produced by the American Museum of Natural History. In the series, Museum paleontologists answer the most frequently asked questions about dinosaurs.

To watch the videos, go to www.amnh.org/explore/amnh-tv. Click on the "Dinosaurs Explained" Tab on the left side of the page. In the playlist, start with the first question and play each video consecutively for a mini-course in dinosaur fossils.