1. Species Diversity and Succession

2. -Variability in genetic makeup among individuals in a pop.
Genetic Diversity
-Variability in genetic makeup among individuals in a pop.
-If too little DNA differences, can lead to genetic bottleneck extinction.
Bottleneck Effect

3. Causes of Bottlenecks Mass hunting
Sudden, natural cause (hurricanes, tornadoes)
Loss of food source/habitat

4. Deserts and mountain tops = LOW diversity, Low number of species
Species Diversity
# of Species in an Area
Tropical rain forest/coral reefs = HIGH diversity, High number of species
Deserts and mountain tops = LOW diversity, Low number of species

5. Ecotone Transitional zone where 2 or more communities meet
Intertidal zones

6. Factors That Determine Species Diversity
Habitat stress
Available niches
Dominance of species
Geological history
Mountain Lion Stress

7. Species Considered separate species if they cannot interbreed
Same species create viable offspring
YES Panda Babies!
NO Dog-Cat Babies!

8. Exceptions to the Rule
Liger

9. Mule

10. Zorse

11. Grolar/Pizzly Bear?

12. SUCCESSION

13. Communities Change Over Time
Succession: a process of community development that involves a changing sequence of species

14. Species land on new material and colonize (pioneer community).
Primary Succession
Starts with new land.
Species land on new material and colonize (pioneer community).
Starts with lichens, moss, and progresses to large trees after 1,000’s of years.

16. 1) Lichens: Can be N fixers  Put Nitrate into soil for other plants to grow! Can also measure air poll.

17. 2) Small Shrubs and mosses (little roots), provide habitat

18. 3) Young pine trees more habitat

19. 4) Mature hardwood and deciduous forests climax community

20. Secondary Succession Starts with already formed land.
Species land on disturbed material.
Disturbance usually caused by fires, storms, and man.

22. Fire Succession in Chaparral
Needed for:
Reproduction
Clearing out competitors
Germination (seed sprouting)

23. As Ecosystems Mature Increase in: Diversity & pop numbers
System stability
Biomass
Nutrient Hold Capacity