Piece of fossilised shark tooth

Datelate Oligocene to early Pleistocene

Object number00051059

NameShark tooth

MediumFossilised shark tooth

DimensionsOverall: 50 × 25 × 4 mm, 9 g

ClassificationsAnimals and animal products

Credit LineANMM Collection

Terms

DescriptionA collection of fossilized shark teeth and whalebone from the Portland region in Victoria. Both the teeth and whalebone are from prehistoric sharks and whales. They range in size and shape, giving an indication of the type of prehistoric animal and its size during the early period of their evolution.HistoryShark skeletons are composed of cartilage instead of bone and the teeth are often the only parts of the shark to survive as fossils. Fossilised shark teeth can date back hundreds of millions of years. The most common, however, are from the Cenozoic Era - 65 million years ago to present. Sharks shed their teeth shed continually throughout their lifetime, and new ones regularly replace the old. A tooth becomes a fossil when it is buried in sediment (or other material) soon after being lost from a shark's mouth. The sediment precludes oxygen and harmful bacteria from reaching the tooth and destroying it. The general fossilisation process varies but in general it takes approximately 10,000 years for a tooth to become a true fossil. The colour of a tooth is determined solely by the colour of sediment in which it is buried while fossilising. The tooth absorbs minerals from the surrounding sediment, so color is not an effective indicator of a tooth's age. The most common colour for shark teeth is a black root with a grayish crown. SignificanceThese fossilised teeth and bone are prehistoric ocean life from millions of years ago.