Classification

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Classification

• Chapter 18

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18-1 History of Taxonomy
Classification
18-2 Modern Phylogenetic Taxonomy
18 -3 Modern System of Classification
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History of Taxonomy

• Taxonomy
• Classification based on similar charactersitics
  evolutionary history
• Early Aristotle? animals plants
• Mid-1700s Carolus Linnaeus
• 7 Levels of Classification
• Kingdom, Phylum/ Division, Class, Order, Family,
  Genus, Species
• Determined by morphology initially
• Dichotomous keys
• Binomial Nomenclature Genus Species (Latin)
• Phylogeny classify by evolutionary history

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Traditional Classification
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Modern Phylogenetic Taxonomy

• Systematics
• Organizing living things by evolution
• Phenetic Systematics
• Based on morphology (phenotype)
• Cladistic Systematics
• Based on derived characteristics
• Feature that evolved in one group (feathers,
  claws, hair)
• Non-traditional conclusions see slide 7
• Uses dichotomous forks
• Does organism have hair?
• Yeshorse, seal, lion, cat
• No lizard
• Ignores morphologic divergence

See cladogram Slide 6
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Cladograms
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Phenetic v. Cladogram
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Modern Phylogenetic Taxonomy

• Classical Evolution Systematics
• Fossil Record
• Morphology homologous
• Embrological development
• Zygote? blastula? blastospore? part of digestive
  system (echinoderms vertebrates)
• Chromosomes Macromolecules
• DNA, RNA, Proteins
• Compare karyotypes

Blastula
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Phylogenetic Trees
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Modern Classification Systems

• 6 Kingdom System
• Based on 4 pieces of evidence
• Archaebacteria
• Eubacteria
• Protista
• Fungi
• Plantae
• Animalia

• 3 Domain System
• Based on ribosomal RNA (rRNA)
• Archaea
• Bacteria
• Eukarya