Because the organism is distributed across the world, and isn't seen anymore, scientists can conclude tat they must have evolved. They can compare one species to the fossils they may have found, and determine that they were related. Then by looking at the species on another part of the world compare the same fossils to other animals and determine that they are similar, sharing a common ancestor.
Nearly all plants are autotrophs, organisms that produce their own food. All plants are eukaryotes that contain many cells. In addition all plants cells are surrounded by cell walls
