Plant Taxonomy - Kingdoms and Domains

1. Carl Linnaeus in his book Systema Naturae published in 1735, classified 4,400 species of animals and 7,700 species of plants.

Linnaeus's prime contribution to taxonomy was to establish conventions for the naming of living organisms that became universally accepted in the scientific world—the work of Linnaeus represents the starting point of binomial nomenclature.

2. The formal taxonomic category Protoctista was first proposed in the early 1860's John Hogg, who argued that the protists should include what he saw as primitive unicellular forms of both plants and animals. He defined the Protoctista as a "fourth kingdom of nature", in addition to the then-traditional kingdoms of plants, animals and minerals.

The kingdom of minerals was later removed from taxonomy by Ernst Haeckel, leaving plants, animals, and the protists as a “kingdom of primitive forms.

3. Edouard Chatton (1883 — 1947), was a French biologist who first distinguished between the eukaryotic and prokaryotic systems of cellular organisation, and coined the terms themselves in his 1925 paper, Pansporella perplex: Reflections on the Biology and Phylogeny of the Protozoa.

4. Herbert Faulkner Copeland (1902-1968) , an American biologist who contributed to the theory of biological kingdoms.  He was responsible for the fourth kingdom, Monera.

5. In 1968, R. H. Whittaker proposed an additional kingdom for the Fungi.

6. Carl Richard Woese, an American microbiologist who defined the Archaea (a new domain or kingdom of life) in 1977 by phylogenetic taxonomy of 16S ribosomal RNA, a technique pioneered by Woese and which is now standard practice.

7. Carl Richard Woese, in 1990,  redrew the taxonomic tree, divided life into 23 main divisions, all incorporated within three domains: Bacteria, Archaea, and Eucarya.

1	2	3	4	5	6	7
Linnaeus	Haeckel	Chatton	Copeland	Whittaker	Woese et al.	Woese et al.
1735	1866	1937	1956	1969	1977	1990
2 kingdoms	3 kingdoms	2 empires	4 kingdoms	5 kingdoms	6 kingdoms	3 domains
(not treated)	Protista	Prokaryota	Monera	Monera	Eubacteria	Bacteria
					Archaebacteria	Archaea
		Eukaryota	Protista	Protista	Protista	Eukarya
Vegetabilia	Plantae			Fungi	Fungi
			Plantae	Plantae	Plantae
Animalia	Animalia		Animalia	Animalia	Animalia