Gordon Hubbell and a crew of fossil hunters were digging holes in the desert of Peru in 1988. This desert is one of the driest places on Earth. It gets almost no rain. Hubbel was digging and found jawbones and more than 200 sharp teeth. He is an expert in fossilized sharks, so he recognized the teeth right away. They were shaped like triangles and came to a very sharp point. They belonged to a distant relative of the great white shark!
How could Hubbell "prove" that these teeth were from a relative of the great white shark?