The reason angiosperms make-up 90% of the vegetation on the Earth is because of its structure. Angiosperms attract bugs to the plant, and then pollen attaches to the bug and is carried to other flowers. Angiosperm seeds are contained into watertight containers filled with food. This food allows angiosperms to grow faster. Animals also do the dispersal of the seeds. The seeds are eaten by animals and are excreted and the seed grows quickly in a pile of fertilizer.

One of the biggest questions about the angiosperms is if they were first woody tree shrubs or small herbs. The Paleoherb hypothesis has been promoted by cladistic analysis that early angiosperms were tropical flowering plants with uncomplicated flowers and a mix of monocot and dicot features. If this was the case, climate or geography provided the opportunities for the angiosperms to diversify. The other hypothesis is that early angiosperms were first woody trees or shrubs. Based on cladistic analysis it is believed that angiosperms are similar to the members of the Magnoliales and Laurales groups that still exist today. Magnoliales and Laurales are comprised of plants that are small and medium sized trees with long, broad leaves and large flowers. Both hypotheses need more investigation before either can be accepted as the true origin of the angiosperm.