New Scientist
Image: Jesse Pruitt
About 310 million years ago some sharks had saws for jaws – and now we know how one of those sharks, called Edestus, fed. The “saw blade” in its lower jaw glided backwards and forwards like the blade on some modern power tools, allowing the shark to cut through soft prey like fish.
We know that Edestus was a very odd shark that grew to the size of a modern great white. It had what look a lot like two saw blades in its mouth – one in the upper and one in the lower jaw. The two blades, which could each be 40 centimetres long but just 3 cm wide, seem to have locked together when the shark closed its mouth, a bit like the blades on a pair of serrated scissors. But exactly how the two blades worked together to cut through flesh has been unclear. Read more on newscientist.com…
