Are sharks really older than trees?

Experts have clarified that sharks are indeed more ancient than trees, although the exact timeline depends on how one defines a shark. Modern sharks emerged around 195 million years ago during the Jurassic period, while fossils of ancient sharks trace back to living lineages like Hexanchiformes, characterized by six or seven gills and a single dorsal fin. These modern sharks are not older than trees.

Trees first evolved during the Middle Devonian epoch, approximately 380 to 390 million years ago, with the first true tree, Archaeopteris, discovered in a 385 million-year-old fossil forest. Other early trees, such as Eospermatopteris and Calamophyton, appeared even earlier, around 390 and 393 million years ago, respectively.

However, the definition of sharks becomes more complex when looking at their extinct relatives. Fossils of these sharks can be traced back through the Permian period and into the Devonian period, around 359 to 420 million years ago. The most common group, hybodonts, are extinct spiny fish with unique calcification patterns in their cartilage similar to modern sharks.

These sharks first appeared around 400 million years ago, before trees emerged. Their rough skin can be traced back to 450 million years ago, with dermal denticles first appearing in the fossil record.