Plant kingdom

Article By:

Chase, Mark W. Molecular Systematics Section, Jodrell Laboratory, Royal Botanical Gardens, Kew, Surrey, United Kingdom.

Fay, Michael F. Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, United Kingdom.

Last reviewed:January 2021

DOI:https://doi.org/10.1036/1097-8542.523300

The worldwide array of plant life, including plants that have roots in the soil, plants that live on or within other plants and animals, plants that float on or swim in water, and plants that are carried in the air. Fungi used to be included in the plant kingdom because they looked more like plants than animals and did not move about. It is now known that fungi are probably closer to animals in terms of their evolutionary relationships (although not similar enough to be considered animals). Also once included in plants were the “blue-green algae,” which are now clearly seen to be bacteria, not plants, although they are photosynthetic (and presumably the group of organisms from which the chloroplasts present in true plants were derived). The advent of modern methods of phylogenetic DNA analysis has allowed such distinctions, but even so, what remains of the plantlike organisms is still remarkably divergent and difficult to classify.

The content above is only an excerpt.