The ocean predators that survived every major extinction event

These early sharks didn’t resemble modern great whites. They were more primitive, almost like armoured ribbon fish. But they already had one thing going for them: cartilage-based skeletons that were lighter, more flexible, and more adaptive than bone. That evolutionary advantage gave sharks an edge over their bony-finned competitors.

Sharks outlasted the meteor that ended the dinosaurs 66 million years ago. (file)

Sharks have outlived extinctions that wiped out most life

Sharks lived through the Permian-Triassic extinction event, the most catastrophic extinction in Earth’s history. It wiped out over 90% of marine life, but sharks managed to survive. They also outlasted the meteor that, reportedly, ended the dinosaurs 66 million years ago.

Even today, some species, such as the Greenland shark, can live over 400 years, making them among the longest-lived vertebrates on Earth.

While we marvel at Polaris, the North Star, it’s actually a relatively young landmark in the night sky. Because of Earth’s slow axial wobble—a process called precession—the North Star changes every few thousand years. A few millennia ago, it was Thuban in the Draco constellation. Before that, it was Vega. And long before any of these celestial stars guided sailors and dreamers, sharks had already roamed the seas for hundreds of millions of years.

Despite their resilience, sharks today face a threat that may prove fatal: humans. With over 100 million sharks killed every year for fins, meat, and bycatch, their numbers are in rapid decline.

There are over 500 species of sharks, ranging from the well-known great white to the ghost-like frilled shark, which resembles a sea serpent more than a modern predator. Many of them are now classified as endangered.

Sharks may be older than trees, but if we’re not careful, they could disappear before the next North Star takes its turn in the sky.