Dinosaurs: Physical Characteristics
Did dinosaurs have scales? What colors were they? And were they warm- or cold-blooded? A dinosaur experts answers 12 questions.
- Grades: 3–5, 6–8
Q: Did dinosaurs have scales like a snake or fish?
A: All dinosaurs we know of had scaly skin with pimply patterns, a lot like alligator handbags.
Q: Do you know what color dinosaurs were? If you do, how do you know? Do you have a personal opinion on this subject?
A: Nobody knows what color they were. Chances are they came in many colors. Their ancestors, reptiles, can be colorful, and their descendants, birds, are very colorful. Dinosaurs lived in many different environments and it was probably in their interest to be colored to blend into those environments to hide from hunters. For instance, little plant-eating dinosaurs that lived in the sandy Gobi Desert of Mongolia might have been tan colored to blend into the background so velociraptors would have a harder time finding and eating them. Dinosaurs in the forests might have been green and brown.
Q: Did dinosaurs have ears? And, if they did, how good was their hearing?
A: We don't know if dinosaurs had ears, since soft tissue isn't preserved as fossils. They probably did not have ears that stuck out like ours, since their closest relatives, birds, and their ancestors, reptiles, don't. But those animals could hear, and dinosaurs have nerve canals in their skulls that seem to be placed where they would help in hearing. Whether they had as good hearing as us (or dogs which are much better than us at hearing) we don't know. I guess they heard pretty well.
Q: Why do some dinosaurs have long tails?
A: We don't know why dinosaurs had long tails but it was probably to keep them from falling on their faces. Dinosaurs leaned forward over their hips and carried a lot of weight in the front of their bodies.
Q: How long is a raptor's tail?
A: A raptor's tail was about as long as its body. Raptors ranged in size from the length of a German shepherd to the length of a truck! So the longest raptor tail may have been about six to ten feet long! It stuck straight out and didn't droop to the ground.
Q: What did ichthyosaur look like when it was alive?
A: Ichthyosaurs looked a lot like little dolphins, or tuna fish (not in the can). Unlike other giant marine reptiles of dinosaur times they didn't use their flipper paddles for swimming power. It was their strong tail flapping sideways, like a shark's, that made them move. They gave birth to live babies in the water. We know this because we have fossils of mothers about to give birth! They were about six feet long and lived in Europe, Greenland and North American seas from the Early Jurassic to the Cretaceous Periods.
Q: Did all ceratopsians have sprawling front legs or semi-sprawling?
A: Scientists disagree in their theories as to how horned dinosaurs walked. Some think that these dinosaurs spread their legs sideways a bit, but others think they walked like other dinosaurs with their legs straight underneath them.
Q: Is it true that the warm-blooded deinonychus had feathers and fur?
A: We don't know for sure if deinonychus or any other dinosaur was warm-blooded, but because it was small and fast-moving there is more chance it was than some other dinosaurs. We do know some dinosaurs grew as fast as the warm-blooded birds when they were young, but dinosaurs might have had their own strategy, part hot- and part cold-. We don't have any evidence of dinosaurs with feathers, unless you include birds which probably came from small, meat-eating dinosaurs. As for fur, that is something found on mammals. Dinosaurs are not mammals — they laid eggs, didn't have hair or fur, and didn't nurse their babies.
Q: Was gigantosaurus warm-blooded or cold-blooded?
A: We don't know if any dinosaurs were warm- or cold-blooded for sure, though many dinosaur bones show some similarities with birds, which are warm-blooded. We don't have evidence from giganotosaurus on warm-bloodedness.
Q: Did the allosaurus dinosaur have lizard hips or bird hips?
A: All meat-eating dinosaurs — called theropods — including allosaurus, had lizard-hipped bodies. Another name for it is saurischian dinosaurs. It's a little confusing since the lizard hips not the bird hips, and meat-eaters in particular, were the ancestors of birds.
Q: How long could a plesiosaur's neck grow to?
A: Plesiosaurs not dinosaurs, but giant marine reptiles, or giant sea creatures, so I don't know much about them. The biggest of the plesiosaurs, elasmosaurus, lived in what is now Kansas and grew to 46 feet long. More than half of that — about 26 feet — was neck!
Q: How big was the heart in a brachiosaurus?
A: We don't know how big the hearts of any dinosaurs were, since soft parts of the inside of their bodies don't preserve as fossils. It is likely that brachiosaurus and other big four-legged plant-eaters had huge hearts since they had to pump blood all over their vast bodies including up their long necks. I'd guess their heart was larger than you are.