A 330 million year old shark head fossil has been found in Mammoth Cave, Kentucky. Mammoth is a Limestone cave. The limestone was deposited at a time that both Kentucky and Arizona were at the bottom of an ocean.
Rocks of this age in Pinal County have almost all been erroded, but a few outcrops can be found. You can stop by the museum, for instance, and see the Pinal Limestone (pictured at right, with fossil corals) that was deposited about the same time the shark died in Kentucky. That shark also probably swam in the waters above Arizona.
Fossils of sharks other than their teeth are rare. Most of a shark's body is cartilidge (like the center of your nose, or in the outside parts of your ears). Cartilidge does not fossilize well. Shark teeth, though, are among the most common fossils. They are made of bone, and very hard, and a typical shark may grow and shed teeth in the thousands during their lifetime.
Link to article on CNN: https://www.cnn.com/travel/article/mammoth-cave-sharks-scn-trnd/index.html
You can see a number of fossil shark teeth at the Museum, including Megalodon teeth, from the extinct animal that was the largest known shark at over 50 feet. Kids can also find and take home fossil shark teeth from our fossil dig.
