fossil, stone tools

• Fossils are preserved remains of dead organism from years ago
• Fossils form hard body parts which don't easily decay or be replaced by minerals
• Fossils are formed from preserved faces of organisms(footprints) that are covered by layers of sediment to eventually become rock
• Two fossil skeletons from Africa named ardi and Lucy provide evidence that humans and apes involved from common ascestor
• Ardi

  • Lived 4.4 million years ago
  • Arms and legs like ape
  • Probably walked upright like a human
• Lucy

  • Lived 3.2 million years ago
  • Had small ape like skull
  • Had carved human feet
  • Walked upright like a human
• Because of fossils scientists discovered humans involved 1.6 million years ago
• Factors to show how old stone tools are

  1. Simple tool is older
  2. Tool found in deeper rock layer is older
  3. Tool made from carbon can use carbon dating to find age
• Stone tools

  Provided evidence for human evolution. Humans used tools made from stone 2.5 million years ago
• • Early tools- sharp pebbles for cutting food
  • Later tools- advanced such as axe for hunting
• Fossils discovered by Mary Leakey and Louis in 1950s helped support theory of natural selection especially in early fossil which contained remnants of stone tools and homohabilis which is now can important early human species