Sharks are roughly 450 million years old — older than trees, older than forests, older than the first broad leaves. When they first appeared, life on land was still mostly low, simple mats of early pl

To say that sharks are older than trees sounds like one of those comparisons made for effect. In this case, the comparison is not empty. The shark line reaches back into a version of Earth where the land had not yet become the vertical, shaded, root-bound world we now recognise. The careful wording matters. Modern […] To say that sharks are older than trees sounds like one of those comparisons made for effect. In this case, the comparison is not empty. The shark line reaches back into a version of Earth where the land had not yet become the vertical, shaded, root-... [6796 chars]