6. Fossil Record Biochemical - DNA Comparative Anatomy Biogeography Observable Events

17. 1. Stabilizing 2. Directional 3. Disruptive

18. When the average is favored over either of the extremes in a population.

20. This happens when one of the “extremes” is favored in an environment over the other extreme or the old average.

22. This situation happens when either extreme is favored over the average.

29. Individuals die, species go extinct

30. As the environment changes, organisms must have variations that allow them to survive (adapt) to those changes or die If an entire population of a species cannot adapt, that species becomes extinct.

31. There have been at least 5 MASS extinctions during Earth’s history where a huge % of the living species were destroyed At least one of these has been attributed to meteor impact and its consequences.