<P> This article attempts to place key plant innovations in a geological context . It concerns itself only with novel adaptations and events that had a major ecological significance, not those that are of solely anthropological interest . The timeline displays a graphical representation of the adaptations; the text attempts to explain the nature and robustness of the evidence . </P> <P> Plant evolution is an aspect of the study of biological evolution, predominantly involving evolution of plants suited to live on land, greening of various land masses by the filling of their niches with land plants, and diversification of groups of land plants . </P> <P> In the strictest sense, the name plant refers to those land plants that form the clade Embryophyta, comprising the bryophytes and vascular plants . However, the clade Viridiplantae or green plants includes some other groups of photosynthetic eukaryotes, including green algae . It is widely believed that land plants evolved from a group of charophytes, most likely simple single - celled terrestrial algae similar to extant Klebsormidiophyceae </P>

When did seeds first appear in fossil record