Scientists have recognized three Ediacara assemblages that lived between 575 and 542 million years ago. These are in geochronological order, the Avalon, White Sea and Nama assemblages, all of which preceded the Cambrian explosion of animals. The left panel shows that number of genera (black line) and how they are dissimilar from each other (gray line) in the three Ediacara assemblages. The right panel shows morphospace occupation of the three Ediacara assemblages. Although there are fewer genera in Avalon than latter assemblages, Avalon fossils occupy the full range of Ediacara morphospace, indicating an explosive evolutionary pattern (the Avalon explosion) similar to the Cambrian explosion of animals that occurred about 542 million years ago.