Sharks Older Than Trees

It’s difficult to imagine a world without forests, but for the first few billion years of Earth’s history, the land was largely barren. While the continents were still rocky and sparsely covered by low-lying mosses and primitive plants, the oceans were already home to some of nature's most successful predators. The earliest shark ancestors began patrolling these ancient seas over 450 million years ago. For a staggering 100 million years, these creatures thrived in a world where the tallest thing on land might have been a large fungus or a fern-like shrub.

The arrival of the first true trees, like the fern-like Archaeopteris around 350 million years ago, was a revolutionary event that transformed the planet's landscape and atmosphere. Yet, by the time these first forests took root, sharks had already established themselves as a dominant and enduring lineage. Their evolutionary design, from cartilaginous skeletons to replaceable teeth, proved so effective that they have survived multiple mass extinctions, including the one that wiped out the dinosaurs (Review). This incredible longevity makes the shark lineage one of the greatest survival stories in natural history, predating not only trees but also insects, amphibians, and nearly all life as we know it on land.