Evolution evidence

• Fossil


  Remains of animals or plants that have become mineralized and changed into rocks over a long period of time
• The deeper underground you go, the older the fossils get
• Fossil record


  The sequence of fossils showing how organisms have changed over time
• The fossil record is evidence for evolution
• In the oldest rocks, only fossilized bacteria are found, while in more recent rocks, fossils of more complex organisms are found
• Plant fossils occur before animal fossils, suggesting plants evolved before animals
• Fossils show closely related organisms have come from the same ancestor
• Fossil record of the horse

  • Eohippus (20cm high) 60 million years ago
  • Horses getting bigger over time
  • Feet changing from 4 toes to 1 hoof
• Bacteria and Atlantic/tomcod


  Organisms useful for studying evolution in a lab setting due to their fast reproductive rates
• Molecular comparison of DNA and proteins


  Provides evidence for evolution by showing similarity between closely related species
• 99% of all species that have ever lived on Earth are now extinct
• Extinct species


  • Woolly mammoth
  • Tasmanian Tiger
• Seed banks


  Repositories for preserving seeds of many plant species, to help maintain biodiversity and allow reintroduction if needed
• The Svalbard seed bank in Norway stores thousands of seeds deep underground in the ice to preserve them