Natural selection & evolution

• What is evolution?

  Gradual change in inherited characteristics
• What is natural selection?

  Process where better-adapted organisms survive
• What are the key points of evolution by natural selection?

  1. Wide range of variation in species
  2. Variation due to genetic differences
  3. Survival of individuals best suited to environment
  4. Successful genes passed to offspring
  5. Repeated process leads to new species
• What happens during speciation?


  A population separates and evolves differently
• How do two groups become different species during speciation?

  They evolve due to genetic variation and selection pressures
• What are some sources of evidence for evolution?

  • Fossils from bones and shells
  • Organisms trapped in amber or ice
  • Footprints covered by sediment
  • Antibiotic resistance in bacteria
  • Molecular comparisons like DNA sequencing
• What is classification in biology?

  Sorting living organisms into groups
• Why do scientists classify organisms?

  To identify species and predict characteristics
• What is artificial classification based on?

  Observable characteristics of organisms
• What is the binomial naming system?

  Standardized naming using genus and species
• Why is the binomial naming system important?

  It helps accurately identify species worldwide