Chances are, you have a pretty good idea what a plant looks like. Roots, stems, leaves, flowers ... these are the things that make plants, plants. But it wasn’t always so.
Plants arose some 500 million years ago, and the fossil record is full of bizarre evolutionary dead-ends, as well as amazing innovations. For example, some extinct ferns looked much like modern ferns on the outside, but their insides appear jumbled. And then, there's the fact that early plants had no leaves.