extinction

• Extinction occurs when there are no remaining individuals of a species alive.
• Animals that have not adapted well to their environment are less likely to survive and reproduce than those that are well adapted. The animals that have not adapted to their environment may become extinct.
• Extinction has a role in evolution as some species disappear. Others survive and continue to evolve.
• Several factors can cause a species to become extinct. They include:

  • new diseases
  • new predators
  • new, more successful competitors
  • changes to the environment over geological time, such as climate change
  • a single catastrophic event, such as a massive volcanic eruption or a collision between an asteroid and the Earth