Classification

• What is the purpose of classification in biology?

  To organize living organisms into groups
• How has the method of classifying organisms changed over time?

  The methods have evolved from artificial to natural classification systems
• What are the two main types of classification systems in biology?

  • Artificial Classification Systems
  • Use observable features
  • Examples include grouping by physical traits
  • Natural Classification Systems
  • Use evolutionary relationships
  • Consider ancestry and structural similarities
• What do artificial classification systems rely on?

  Observable features
• What is an example of a feature used in artificial classification?

  Whether an organism can fly or not
• What do natural classification systems use to classify organisms?

  Information about organisms' ancestors and structural forms
• How are bats and humans classified together in natural classification systems?

  They are grouped together due to similarities in bone structure
• What are the hierarchical levels of classification in biology?

  1. Kingdom
  2. Phylum
  3. Class
  4. Order
  5. Family
  6. Genus
  7. Species
• What is the smallest unit in the classification hierarchy?

  Species
• How is a species defined in biological classification?

  A group of similar organisms that can reproduce to give fertile offspring
• How have developments in biology improved classification systems?

  • Invention of the microscope allowed detailed examination of organisms
  • Advances in technology lead to new discoveries about relationships
  • DNA sequencing reveals evolutionary relationships
• What role does DNA sequencing play in classification?

  It compares the genetic sequences of different species to determine relatedness
• What does a higher similarity in DNA sequences between species indicate?

  That the species are more closely related
• What percentage of DNA sequence is similar between humans and chimpanzees?

  About 94%
• What is the main difference between artificial and natural classification systems?

  • Artificial Classification:
  • Based on observable features
  • Natural Classification:
  • Based on evolutionary relationships and ancestry