Flowers Invaded a Green World

The world became seriously green 475 million years ago. The first real terrestrial plants resembled moss, but they later developed roots and turned into the groups that dominated Earth before the flowers.

Among them were forms such as liverworts, ferns, seed ferns, cycadophytes, ginkgophytes, conifers, and 30-m-high relatives of modern clubmoss. Some of them have descendants that we can still see today, when we take a walk in a dense old-growth forest.

The prehistoric plants did not have colourful flowers nor did they make much use of insects for reproduction purposes. Instead, they spread their pollen or spores via wind or water. When the first flowering plants appeared in the early Cretaceous, the number of early plant species began to be dramatically reduced.