1735
Two kingdoms
Carolus Linnaeus distinguished living things into two kingdoms: Animal kingdom Regnum Animale and vegetable kingdom, for plants (Regnum Vegetabile).
Three kingdoms
Ernst Haeckel added a third kingdom: Protista, for organisms which were neither animal nor plant.
1866
1960s
Four kingdoms
A rank above kingdom, a domain was needed to distinguish between prokaryotes and eukaryotes and kingdom Monera was added.
Five kingdoms
Robert Whittaker recognized an additional kingdom for the Fungi.
1969
- See also:
- Classification