Great whites are warm-blooded migrants with three ocean clans
Carcharodon carcharias ranks among the largest living sharks, grey above and white below, with roughly three hundred replaceable serrated teeth. Partial warm-bloodedness keeps it active in cool seas. Nuclear DNA now splits populations into North Atlantic, Indo-Pacific, and North Pacific clades that parted tens to hundreds of thousands of years ago.
Females mature near four point six to four point nine metres and one to one point nine tonnes; males mature smaller. Reliably measured maxima sit around six metres and about two thousand five hundred thirty kilograms—nineteenth-century claims past eleven metres are dismissed. A fatty liver can exceed a quarter of body mass for buoyancy and fuel. Jaws swing forward on muscle alone; models scale a six-point-four-metre bite past eighteen thousand newtons at the rear. Juveniles start on fish with slender teeth, then broaden and serrate them as mammals enter the diet.
The lineage emerges in Pacific fossils about six to five million years ago from Carcharodon hubbelli, itself derived from unserrated C. hastalis. By the end of the Pliocene whites had spread globally as megalodon faded. A twenty twenty-four nuclear study found three major branches diverging roughly one hundred thousand to two hundred thousand years ago; a twenty twenty-five analysis affirmed the same clades but timed the split nearer seven thousand years after a long population decline. Cold Benguela water and warm equator belts still limit mixing.
They roam coasts and open ocean, hunting seals, dolphins, squid, fish, and scavenging whales—yet orcas sometimes flip the food chain. Solitary habits yield to feeding aggregations with body-language hierarchies. Pups hatch inside the mother before live birth. Despite Jaws mythology, most human bites look like curiosity or mistaken identity. IUCN lists the species vulnerable worldwide and critically endangered in European and Mediterranean waters, hit by bycatch, sport fishing, and beach nets.
Source: Great white shark
