Classifying Nature

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Classifying Nature

• Linnaeus, Buffon, Cuvier, Whittaker

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Linnaeus (Carl von Linnae, 1707-1778)

• Swedish naturalist who studied medicine in the
  Netherlands.
• Main concern was naming and classifying natural
  objects.
• Studied plants in Dutch gardens that had been
  collected from around the world.

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Linnaeus

• Journeyed to Lapland to study the animals and
  plants, later published Flora Lapponica in 1737.
• Soon after his return, Linnaeus was offered a
  position as house physician and garden curator to
  George Clifford, a wealthy merchant.

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Linnaeus

• 1735 Linnaeus published Systema Naturae, his
  first system for ordering natural history. He
  admitted that it was an artificial rather than
  a natural system, but felt that its utility
  justified using a less natural system.
• Linnaeus choice of terms reflect his cultural
  background. Referred to plant stamens as andria
  (husband) and pistils as gynia (wife). His
  writings refer to marriages between plants,
  including multiple spouses and concubines.
  Shocking to other Dutch naturalists, but his
  terms were adopted nevertheless.

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Linnaeus

• 1736 Linnaeus formally publishes his system of
  binomial nomenclature. Proposes that all natural
  objects, including plants, animals, minerals,
  etc. receive a single name consisting of a genus
  and a specific epithet.
• 1753 Linnaeus publishes the Species Plantarum, a
  description and classification of known
  organisms. Included are human beings, given the
  species name Homo sapiens. Interestingly,
  Linnaeus also placed the known great apes in
  genus Homo.

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Georges-Louis LeClerk, Compte de Buffon
1707-1788

• Buffon was a competitor of Linnaeus, advocating
  for the development of a natural system of
  classification.

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Buffon

• Buffons taxonomy was based on natural
  families. He noted, for example, that wolves,
  foxes, and dogs all have similar features, and
  constitute a natural family. Horses, zebras, and
  donkeys would belong to a different natural
  family.
• Later Buffon would propose an early theory of
  evolution, describing how organisms could change
  by their environment into similar species within
  the same natural family.

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Georges Cuvier 1769-1832

• Studied Buffon, and agreed that there should be a
  natural taxonomy.
• However, Cuvier parted with other taxonomists at
  the time, as he believed the taxonomic system
  should not be hierarchical.

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Cuvier

• Cuvier used internal anatomy of animals to sort
  them into categories, based mainly on neural
  anatomy Vertebrata, Mollusca, Articulata, and
  Radiata.
• Comparative anatomist looking for patterns in
  structure, especially among vertebrate animals.

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The Two Kingdom System

• Linnaeus two-kingdom system for living organisms
  was practical for naturalists working in the
  field, and eventually took precedence.
• In this system, all living organisms are
  classified as Animals or Plants (the Mineral
  kingdom encompassed the non-living part of the
  world). As time went on and microorganisms were
  studied more, problems arose with the two-kingdom
  system. Some organisms just didnt fit neatly.

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Robert Whittaker (1920-1980)

• Dissatisfied with the two-kingdom system, as many
  single-celled organisms didnt fit well in it.
• For example, Euglena has chloroplasts and
  photosynthesizes like a plant, but is motile and
  can ingest food like an animal.
• Developed first a three-kingdom, then
  four-kingdom and five-kingdom systems.

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Todays System

• Recently, Domains were added above the level of
  kingdom to express how different the two large
  groups of bacteria are from one another.
• Domains
• Archaea
• Bacteria
• Eukarya Protists, Fungi, Plants, Animals

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