The first, including the living great white, has intermediate fossil species that connect it to a relatively smaller C.landanenesis (2-3 metres in length). A second line, recognized as a separate genus, Carcharocles, by some researchers, include gigantic relations that can be traced back about 50 million years. The evolution of these huge sharks is characterized by increasing body size, and one may have lived up to fairly recent times.

The modern great white evolved in Miocene times, about 20 million years ago. At the same times, two other much larger sister species that evolved from the second parallel lineage, called Carcharodon megalodon and C. angustidens, were present in the world’s sea. Teeth of the C.megalodon measuring 17 cm in length were found in Peru, and this indicates that it reached 13 metres or more, and weighed around 20 tons. This huge predator, at least at its largest sizes, probably fed mostly on large baleen whales. Some researchers postulate that it became extinct when the whales evolved a migratory behaviour into polar seas to feed on the abundant plankton there. This would have cut off the huge shark’s main food source for much of the year because they were not temperature adapted to follow the whales into icy seas.

Fossilized teeth of the three species of Carcharodon have been found in southern Africa. Those of the modern great white, C. angustidens are known from KwaZulu-Natal near Uloa in a Lower Miocene deposit, about 15 million years old. Teeth of the larger C. angustidens, measuring up to 15 cm, have been collected from the KwaZulu-Natal locality as well as the Eocene beds in the Eastern Cape and in Namibia. Another close lineage of Paleocene giant sharks without serrated teeth (Family Otodontidae) evolved alongside the Carcharodon species and gave rise to the living porbeagle sharks (genus Lamna).