But since the 1970s, geologists have also noted the existence of another layer, just above the iridium-rich one, that contains “lots and lots and lots of fossil fern spores” and not much else, says ...

In fact, we love them so much, we’ve filled our new Evolution Garden with them. But how much do you know about one of the earliest plants to evolve on our planet? Ferns have been growing on Earth for ...