Natural selection select one: a. cannot occur without genetic drift. b. is the principle cause of extinctions. c. is the principle cause of evolutionary change. d. occurs only in gametes.

3. draw a topographic map that displays the following features: (4 points each) a. the contour interval is 20 meters. b. the point of lowest elevation is 960 meters. c. the point of highest elevation is 990meters. d. there is at least one sinkhole or depression, at any elevation. e. there is at least one steep slope and one gentle slope.