Every fossil tells a story. A paleontologist is a scientist who studies fossils to learn what life was like on planet Earth long ago. Fossilized footprints help us understand an animal’s anatomy, size, weight and even behavior. We can see if it traveled in groups or tended to live alone. Fossilized teeth can give us hints about an animal’s diet. We can even learn about the landscape where a plant or animal lived. If there are fish fossils in what is now a desert, we might hypothesize that the landscape was once a body of water. Learning more about those fish fossils—like their age and what kind of water they lived in—will help us learn even more. Paleontologist are most like detectives who use fossils as

A. clues.
B. theories.
C. suspects.
D. witnesses.