Evolution by Natrual Selection

• Evolution


  The change in the inherited characteristics of a population over time through a process of natural selection
• Natural selection


  1. Genetic variation within a population

  2. Differential survival and reproduction

  3. Passing on of beneficial traits to offspring

  4. Change in population over generations
• The Earth is teeming with living organisms, including large animals, small animals, and plants
• Only about 1% of the total species that have ever lived on Earth are still alive today, the rest are extinct
• Life first developed on Earth more than 3 billion years ago, starting with simple single-celled organisms
• All species of living things have evolved from these simple life forms
• Genetic variation within a population

  • Rabbits have different alleles for traits like fur thickness, eyesight, and hearing
• Environment gets colder


  Rabbits with thicker fur alleles are more likely to survive