Learn about the early years of prehistoric sharks and how they've survived longer than most other animals.

Shark evolution in perspective

Is 450 million years a long time in evolution? Life is thought to have begun on earth about 3.8 billion years ago. Life on earth began as bacteria and did not advance beyond the one-celled format until around 580 million years ago. The first fish appeared around 510 million years ago. These were armored jawless fishes known as ostracoderms. And then came the sharks either 455 or 425 million years ago—there is some disagreement among paleontologists as to when.

Many of us tend to think of dinosaurs as dominating the prehistoric world. But dinosaurs didn’t appear until about 230 million years ago. Mammals first appeared around that same time.  The first human-like animal, or hominid, dates to about 4.5 million years ago, but modern humans only date back perhaps 60,000 years. And recorded civilization has lasted only about 5,000 years. That means sharks have existed 100 times longer than hominids and 3 times longer than dinosaurs (or twice as long as dinosaurs if we include birds).

Sharks in Perspective: Evolution of Animal Life on Planet Earth