1. Parasite Box Model Example Brucellosis (undulant fever) is a bacterial disease of ruminant mammals and sometimes of humans. In ruminants, brucellosis causes a decrease in milk production, and can cause cows to abort their calves. It has been in the news because of concern that brucellosis infected bison in Yellowstone National Park may be able to spread the disease to cattle. Construct a box model and then write equations that show how brucellosis affects a population of bison. Once an animal is infected with brucellosis, it will carry the disease for the rest of its life. There is vertical transmission of the disease from mothers to offspring. In your box models and equations you should account for: x - the # of uninfected susceptible bison, y - the # of infected bison, a - per capita host birth rate for uninfected offspring, b - natural, non-disease mortality rate, alpha α - disease induced mortality rate, beta β - transmission coefficient, and zeta ζ - birth rate of infected young.

2. Symbioses - Mutualism

3. Endosymbiotic Origin of Eukaryotes Lynn Margulis

4. Endosymbiotic Origin of Eukaryotes

5. The earliest eukaryotes acquired mitochondria by engulfing alpha proteobacteria. The early origin of mitochondria is supported by the fact that all eukaryotes studied so far either have mitochondria or had them in the past. Mitochondria have their own DNA and replicate themselves during cell division. Later in eukaryotic history, some lineages of heterotrophic eukaryotes acquired an additional endosymbiont—a photosynthetic cyanobacterium—that evolved into plastids. This hypothesis is supported by the observation that the DNA of plastids in red and green algae closely resembles the DNA of cyanobacteria. Plastids in these algae are surrounded by two membranes, presumably derived from the cell membranes of host and endosymbiont.

6. Stromatolites on coast of Western Australia

7. The Nature of Communities and Ecosystems

8. Sourdough bread – ingredients and final product

9. Redwood Forest

10. Scale of Ecosystem – Lake Superior

11. Scale of Ecosystem – Isle Royale

12. Scale of Ecosystem – Isle Royale – Forest and Pond

13. Scale of Ecosystem – Isle Royale Wetland

14. Scale of Ecosystem – Isle Royale Pitcher Plants

15. Ecotone – region where two communities/ecosystems grade into each other Forest-Marsh Ecotone

16. Stability A stable community or ecosystem is one that has the ability to replace itself – exist in place for more than one generation

17. Douglas-Fir

18. Pea Aphids

19. Life cycle of the Pea Aphid

20. Components of Stability 2 major components: 1) resistance - the ability of a community or ecosystem to avoid disturbance - how most people think of stability 2) resilience - the speed with which a community or ecosystem returns to its former state following a disturbance that has displaced it from its initial condition

21. Ecosystems and Stability Grassland – South AfricaRainforest – Puerto Rico

22. Additional Components of Stability Local stability describes the tendency of a community to return to its original state following a small disturbance Global stability describes the tendency of a community to return to its original state following a large disturbance

23. Adaptive Capacity of an Ecosystem

25. Adaptive Capacity of an Ecosystem - Chesapeake Bay

26. Adaptive Capacity in 3D

27. Current Adaptive Capacity

28. From Local vs. Global Stability dynamically fragile - a community which is stable only within a narrow range of environmental conditions dynamically robust - a community which is stable within a wide range of environmental conditions

29. Complexity and Stability

32. Current understanding - no clear relation between complexity and stability 1) complex, fragile communities of relatively constant environments (the tropical rainforests) are more susceptible to outside, unnatural disturbances than are simpler, more robust communities which experience regular climatic fluctuations (most temperate communities) 2) In stable environments you would expect to find K selected species (high competitive ability, high survivorship, low reproductive output) and such species will resist disturbance 3) In unstable environments you would expect to find r selected species (low competitive ability, low survivorship, but high reproductive output) that have little resistance but high resilience

34. Aerial view Of 1989 Yellowstone Fire

35. Why is the World Green? Boreal Forest Outlined in Green

36. Spiny Water Flea

37. Spiny Water Flea Invasion

38. Mary Power

40. Eel River with steelheadEel River without steelhead