Rolled out, it would become a long round horn with a wide mouth tapering to a tiny point, like a cornucopia - horn of plenty - in a painting by Rubens. Its tubular surface is not smooth but rippled by ...

Ammonites were shelled cephalopods that died out about 66 million years ago. Fossils of them are found all around the world, sometimes in very large concentrations. The often tightly wound shells of ...