Unlike humans, sharks are luckily enough to have several rows of teeth, that continue growing during their whole lifetime along the inside of the jaw until they are needed to replace missing teeth, that are continuously shedded. It is estimated, that some large sharks can produce 50.000 teeth in their life!
Their shape is determined by their prey: sharks that feed molluks and crustaceans have dense flattened teeth to crush their prey, like the zebra shark, and sharks like the porbeagle have needle-like teeth for gripping. The fierce large predators lik the great white and tiger have pointed lower teeth for gripping and upper teeth with serrated edges, that are excellent for cutting of chunks of prey. Filter feeders like the whale shark only have very small teeth, that have nearly disappeared.
The outside of shark teeth is made up of fluoride, the active component of most toothpaste. The teeth of sharks and humans are both very hard, but unlike sharks, we do not get new ones…
It may seem strange that all the fossilized shark teeth we find are black, but shark teeth buried in sediments absorb surrounding minerals, turning them from a normal whitish tooth color to a deeper color, usually black, gray or tan. The fossilization process takes at least 10,000 years, although some fossil shark’s teeth are millions of years old!
Best of all, they can be found right on the sand, for free. All it takes is a sharp eye, a little effort, and some luck. It is best to search at low tide at the water’s edge.
Do you want to know more about shark teeth? Watch this Animal Planet video:
Want to go looking for fossilized shark teeth? Visit this site: