What People Want to Know About Dinosaurs

What sounds did the dinosaurs make? We've all heard the dinosaurs in movies roaring. The truth is, we do not know if they made sounds at all. Some scientists, basing their speculations on cavities found in some dinosaur skulls, believe that some dinosaurs might have had a voice. What do you suppose a dinosaur would sound like? Why? Why would a dinosaur make a sound?

What colors were the dinosaurs? From the fossil remains, we have no way of knowing. Dinosaurs may have had as wide a range of colors as modern reptiles with special coloration for camouflage and display. Looking at images of dinosaurs, think about how scientists and artists use color in their portrayals of dinosaurs. Why do you think modern animals ended up with the colors that they have?

Did all dinosaurs look alike? Dinosaurs came in a wide range of shapes as well as sizes. Look, for instance, at the various shapes of the necks, legs, and tails. Dinosaurs are grouped by such characteristics. How many different kinds of dogs can you think of? How different to they look?

How do you tell the males from the females? The truth is, we cannot. Remember, all that we know definitely about dinosaurs is what we can find in the fossils. Not many distinctive features of males and females would be fossilized, and there is a special problem. Consider guppies, the common aquarium fish. It can be difficult to believe that the little brightly colored males and the larger, drab females are the same kind of fish. Imagine that thousands of years later, the remains of those fish were found. A paleontologist (a scientist who studies ancient plants and animals) might well be forgiven for identifying two different species, one about twice the size of the other. Some scientists believe that the more extravagant horns, tusks, and crests of some dinosaurs might have been secondary sexual characteristics, rather than characteristics of different species. Parasaurolophus might have blown air through its crest; if so, the sound might have figured in courtship, or the crest itself might have been part of a visual display.

Did all dinosaurs live on earth at the same time? Scientists believe that dinosaurs appeared on earth 245 million years ago and became extinct 65 million years ago. So, dinosaurs spanned 180 million years, with humans appearing later. Not all people agree with this chronology, however.

What killed the dinosaurs? This is one of the greatest controversies about dinosaurs. Theories include drastic changes in the climate, the crash of an asteroid onto the earth, and competition with other animals. But, their disappearance is not as important as the long time that dinosaurs were the dominant life form on earth.

Were all dinosaurs huge? Some dinosaurs were smaller than a large dog. Just as a modern may support mammals as diverse in size as a black bear and a mouse, so in the time of the dinosaurs, there was an even greater diversity in the size of the reptiles.

What was the social life of dinosaurs like? Although we can observe the behavior of modern animals, we often do not know the reason for that behavior. Lions, for example, live and hunt in groups, while tigers are not so social, but we do not know why. Most modern reptiles have little social or family life, but they are so different from the dinosaurs that we cannot assume that dinosaurs had similar behavior. We can tell from nest sites that some dinosaurs probably looked after their young. There are advantages for large herbivores (plant-eaters) like elephants to move in a herd; so, some scientists think that large herbivorous dinosaurs would have acted similarly. What advantages or disadvantages does living in a group have?

How can we find the answers to these questions? Scientists sift through dinosaur sites, looking for any remains, from bones to footprints. Then, they use a range of modern scientific instruments to identify, measure, and try to understand their finds. Other scientists interpret the information with computer programs and comparisons to living animals. Finally, all the information and thoughts come together to form a picture not just of an individual animal but of animals in their natural environment interacting with each other. It will take many people working together to find the answers to these tantalizing questions. How can you get involved in discovering the secrets of the dinosaurs?

Who really cares? Why should we bother studying dinosaurs? The dinosaurs lived on and dominated the earth for many, many millions of years more than they have been extinct. They were not a failure as a life form. In fact, they were quite a success, a success that we need to understand and learn from, so that we can avoid their fate.