Small Mako Shark Tooth Fossil (Sharktooth Hill)

 

This shark, whose teeth can be found in deposits worldwide lived from the Eocene to the Pleistocene. It has been historically classified as a broad-toothed mako shark (Isurus hastalis). It was then reclassified as Cosmopolitodus hastalis making it a type of extinct Mackerel shark.

More recent research has reclassified it as part of the white shark lineage which would make the species Carcharodon hastalis. You can read more about this here. What classification is correct is still under debate leading to lots of different labels for these teeth. We prefer the most recent interpretation and label them as Carcharodon hastalis.

Teeth of this shark have been found up to 3 1/2" in length but teeth over 2 1/2" are uncommon and very rare over 3".

Sharktooth Hill is located in the foothills of the Sierra Nevada Mountains near Bakersfield, California. It represents an exposure of the Temblor Formation, a middle-Miocene marine deposit. 15 million years ago the sea levels were substantially higher and central California was covered by what is known as the Temblor Sea.



There are two highly fossiliferous bone beds in the formation that were created when fossils originally deposited at the bottom of the sea eroded out of the rocks, were concentrated by ocean currents, and subsequently reburied. Because the fossils in these bone beds are reworked, only isolated teeth and bones are found in these beds.

Today, the original Sharktooth Hill is a National Natural Landmark, but there is private property surrounding it on which there are operational pay-to-dig fossil quarries.