Shark teeth are especially valuable for this purpose. Their abundance and durability make them a treasure trove of information about past environments. However, uncovering patterns in ancient ...

Greenland sharks have narrow, pointed upper teeth and broader, squared teeth on the lower jaw. Holding large prey in position with their upper teeth, they roll their head in a circular motion ...

Although mating has never been scientifically observed, scars on female sharks suggest that males use their teeth to hold onto while mating. Based on their estimated growth rate, length and number ...

Remarkably, fossil shark teeth are also incredibly abundant. Sharks ruled the earth's oceans for 400 million years, and every individual grows and sheds thousands of teeth in their lifetime.