1. Parasitism and Disease Lyme Disease Cycle in the UK

2. Lord Robert May Sir Roy Anderson

3. Brucellosis cycle and hosts

4. 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.

5. Spread of HIV in Russia

6. Dynamics of parasite populations Most important parameter is basic reproductive rate of the parasite, symbolized Rp Rp will: 1) increase with increasing density of susceptible hosts - N 2) increase with increasing transmission rate beta β 3) increase with increasing fraction of infected hosts that survive long enough to be infectious to other hosts - symbolized by f 4) increase with increasing average time that host remains infectious - symbolized by L

7. Dynamics of parasite populations We can also examine the reproductive rate of infection (Ri) = average number of secondary cases of infection generated by one primary case in a population where almost everyone is susceptible to infection Ri > 1 each infection has more than one "offspring" - chain reaction of epidemic Ri < 1 infection cannot sustain itself

12. Incidence of HIV in Africa

15. You’re never too old to need protection

17. Symbioses - Mutualism

18. Symbioses Symbioses - species living in close association Parasitism +,- parasite benefits, host harmed Commensalism +,0 or 0,0 can have positive effect for one species or for neither Mutualism +,+ both species benefit

19. Mutualism Definition - the individuals in a population of each mutualist species grow and/or survive and/or reproduce at a higher rate when in the presence of individuals of the other. Each benefits (+,+)

20. General Features of Mutualisms 1. The life cycle of most mutualistic species is very simple (in contrast to parasites) 2. There is no conspicuous dispersal phase for most endosymbionts (endomutualists) 3. Populations of most mutualists are stable in size - no epidemics as seen in parasites 4. The ecological range (niche breadth) of organisms in mutualisms usually appears to be greater than that of either species alone 5. Host specificity is usually flexible 6. Within populations of mutualists, the number of endosymbionts per host is relatively constant

21. Two types of Mutualism Facultative - each partner gains a benefit but is not dependent on the other - the vast majority of mutualisms are facultative (maybe). Obligate - one or both partners is dependent on the other and cannot survive without the other.

22. Mutualisms Involving Links in Behavior

23. Greater Honeyguide

24. Honey Badger

25. Ants and Acacia Trees

26. Beltian bodies (yellow) on Acacia leaves

27. Ant larvae inside Acacia “horn”

28. Pollination Mutualisms

30. Pollination syndromes among the phloxes

31. Cerambycid beetle pollinating a passionflower

32. Honeybee covered with pollen

33. Honeybee pollinating peach tree

34. With visible lightwith UV light Silverweed nectar guides for honeybees

35. Bombyliid bee fly pollinating a composite

36. Fly on Orbea – carrion flower

37. Caralluma – carrion fly pollinated

38. Monarch and Milkweed

39. Tiger Swallowtail and Butterfly Bush

40. Hummingbird pollination

41. Greater double-collared sunbird

42. More Bird Pollination Spiderhunter on banana Malachite sunbird

43. Episcia – moth pollinated

44. Hummingbird moth and columbine

45. Bat pollination

46. Hammer Orchid and Wasp

47. Figs and Fig Wasps

49. Mutualisms involving Culture of Crops or Livestock

50. Leaf-cutter Ants – genus Atta

51. Diagram of Leaf-cutter ant colony nest

52. Human Agriculture Sustainable DairyIndustrial Wheat

53. Digestive Mutualisms Involving Gut Inhabitants

54. Ruminant with multiple stomachs

55. Ruminant by-products

56. Termite Mound Western Australia

57. Termites

58. Mycorrhizae

59. Ectomycorrhizae

61. Mycorrhizae – world’s largest organisms? The mycelium of some forest fungi can extend enormous distances. A single individual of Armillaria bulbosa has been discovered that permeates more than 30 acres of forest soil in northern Michigan and may be one of the world's largest living organisms. Some scientists speculate that it was spawned by a single spore thousands of years ago. Another Armillaria in Washington was recently found to consist of a subterranean mycelial network with erect, above-ground mushrooms covering more than a thousand acres of forest soil. Another Armillaria in Oregon is estimated to extend across 2400 acres. These organisms would weigh thousands of metric tons.

62. VAM – Vesicular Arbuscular Mycorrhizae

63. Nitrogen Fixing Mutualisms

64. Red Clover – A Classic Legume

65. Normal Nitrogen Fixation

66. Legume Root Nodules

67. Rhizobium root nodules on a bean plant

68. Animal-Algae Mutualisms

69. Healthy Coral Reef - Indonesia

70. Coral polyp with zooxanthellae - a dinoflagellate, Symbiodinium

71. Coral polyp – coral animal is green, Zooxanthellae is red