John Hogg (1800–1869) was a British naturalist who wrote about amphibians, birds, plants, reptiles, and

protist A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the exc ...

s. In 1839, he became a member of the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...

. John Hogg is credited with the creation of a fourth kingdom, accompanying

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalise ...

's Lapides, Plantae and Animalia, to classify

Life Life is a quality that distinguishes matter that has biological processes, such as Cell signaling, signaling and self-sustaining processes, from that which does not, and is defined by the capacity for Cell growth, growth, reaction to Stimu ...

, namely ''Protoctista''.

Background

In 1735, the Swedish botanist

formalized living things into two supergroups, in his monumental '' Systema Naturae''. All organisms were placed into the Kingdoms Plantae and Animalia. Linnaeus added a third kingdom of the natural world in 1766; ''Lapides'' (

rock Rock most often refers to: * Rock (geology), a naturally occurring solid aggregate of minerals or mineraloids * Rock music, a genre of popular music Rock or Rocks may also refer to: Places United Kingdom * Rock, Caerphilly, a location in Wales ...

s). These were deemed to be similar to plants in that they were, neither living nor sentient, i.e. not having senses. They were further characterised as solid bodied.

Fourth kingdom

In 1860, Hogg created a fourth kingdom, the ''Regnum Primigenum'' or ''Protoctista''. His rationale was simply that a kingdom of 'first beings' was necessary, as these entities were believed to have existed prior to plants and animals. Hogg attempted to justify his arguments for a fourth kingdom with '' Spongilla'', a freshwater green sponge, that was an animal known to exude oxygen in the light. However, the

photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i ...

was later shown to be a result of symbiotic ' algae'. Such an attempt to apply non-reductionist thought to classification systems during a period of biological debate made Hogg a protagonist within the field of nineteenth century biology along with Ernst Haeckel and

Charles Darwin Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended ...

References

{{DEFAULTSORT:Hogg, John 1800 births 1869 deaths Fellows of the Royal Society