1. Chapter 56 Community ecology

2. Community a group of different species living in one area

3. Species richness The number of species in a community The number of species in a community Increases near equator Increases near equator

4. Relative abundance population of a given species in a specific size ecosystem population of a given species in a specific size ecosystem Compares the percent of each species Compares the percent of each species EX. Percent of mallards in pond compared to total bird population EX. Percent of mallards in pond compared to total bird population

5. Species diversity Relates the number of species to the “relative abundance” of each Relates the number of species to the “relative abundance” of each

6. Species area effect Larger areas usually contain more species than smaller ones Larger areas usually contain more species than smaller ones Evident on islands Evident on islands

7. Individualistic concept Community is made of nothing more than different species that happen to be living in same area Community is made of nothing more than different species that happen to be living in same area

8. Holistic concept Communities are an integrated unit that depend on each other for survival. Communities are an integrated unit that depend on each other for survival. “super organism” “super organism”

9. Keystone Species A species that has great influence on other species in ecosystem A species that has great influence on other species in ecosystem Ex. Sea stars Ex. Sea stars

10. Trophic cascade There is a ripple effect from one eating level to another when keystone specie is affected There is a ripple effect from one eating level to another when keystone specie is affected Orcas increase Orcas increase otters decease otters decease Urchins increase Urchins increase Kelp decreases Kelp decreases

11. Ex. Elk eat Aspen trees

12. Wolves eat elk

13.  wolves influence vegetation Wolf predation near aspen trees increases Wolf predation near aspen trees increases Elk change browsing habits Elk change browsing habits Aspen increase Aspen increase

15. Community stability Resistance to change Resistance to change Biodiversity increases stability Biodiversity increases stability

16. Biodiversity

17. 55.2 Ecological Niche concept

18. Niche The role an organism fills in its community The role an organism fills in its community

19. Niche determined by Habitat Habitat Place in food chain Place in food chain Specific food types Specific food types When they eat or hunt When they eat or hunt

20. Great horned owl and red tailed hawk have different niches Both eat small rodents Both eat small rodents Both live in same area Both live in same area BUT owls hunt at night, hawks hunt during day BUT owls hunt at night, hawks hunt during day

21. Fundamental niche Potential niche – without any competition

22. Realized niche The part they actually use due to competition. Usually smaller

23. Competition exclusion One Species is eliminated from a community because of limited resources. Can not occupy same niche One Species is eliminated from a community because of limited resources. Can not occupy same niche

24. Example paramecium P. Caudatum paramecium declines in presence of other paramecium P. Caudatum paramecium declines in presence of other paramecium

25. Resource partitioning When several similar species subdivide a niche for resources Ex. 5 different warbler species eating different areas of a tree

26. Character displacement One Phenotype is selected because of competition One Phenotype is selected because of competition Ex anoles. Ex anoles. on same island there are populations that eat different things and occupy different niches, on same island there are populations that eat different things and occupy different niches,

28. Character displacement can lead to different selection models Directional, stabilizing and disruptive Directional, stabilizing and disruptive

29. Symbiosis and community Interactions Chp 56.3 - 56.4

30. Food chain One specific sequence of eating levels One specific sequence of eating levels

31. Food web – all the consumer interactions within ecosystem

32. Trophic levels = eating level

33. herbivore

34. Carnivore

35. Omnivore

36. Scavenger Consumer/carnivore that does not hunt Consumer/carnivore that does not hunt

37. Predation +/- Predator captures and kills prey Predator captures and kills prey

38. Predator Prey adaptations Predators – camouflage, sharp teeth, web, infrared sensors, etc Predators – camouflage, sharp teeth, web, infrared sensors, etc

39. Trap door spider Makes camouflaged lair Makes camouflaged lair

40. Angler fish

41. Spider web

42. Green pit viper Has infra red heat sensors in pits Has infra red heat sensors in pits

43. Prey - Survival techniques camouflage – hide camouflage – hide Aposematic – Advertize poison or impalatability by coloration Aposematic – Advertize poison or impalatability by coloration

44. Monarch butterfly Larva eats poison milk weed Larva eats poison milk weed Monarch advertise poison. Aposematic Monarch advertise poison. Aposematic

45. Predators adapt to monarch poison Black backed oriole Black backed oriole Black headed oriole Black headed oriole Black-eared mouse Black-eared mouse

46. Poison dart frogs Advertise poison Advertise poison Aposematic Aposematic

47. Camouflage Stick insect Stick insect

48. Walking leaf insect

49. flounder

50. Leaf Frog

51. Mimicry One species looks like another One species looks like another metalmark moths mimic jumping spiders.

52. Batesian mimicry A normal species mimics a poisonous one A normal species mimics a poisonous one

53. Monarch Batesian mimic

54. Coral snake Batesian mimic

55. Caterpillar mimics coral snake Batesian Batesian

56. Müllerian mimicry More than one unpalatable /poisonous species resemble each other More than one unpalatable /poisonous species resemble each other Bees, wasps and hornets Bees, wasps and hornets

57. Mimicry in Butterflies Is Seen here on These Classic “Plates” Showing Four Forms of H. numata, Two Forms of H. melpomene, and the Two Corresponding Mimicking Forms of H. erato. Mimicry in Butterflies Is Seen here on These Classic “Plates” Showing Four Forms of H. numata, Two Forms of H. melpomene, and the Two Corresponding Mimicking Forms of H. erato.

58. Multiple coral snake mimicry Batesian Batesian

60. Plant / herbivore interactions

61. Plants may use physical defenses Thorns Thorns

62. Sticky Hairs

63. Tough leaves

64. chemical defenses secondary compounds Poisonous Poisonous Irritating Irritating Bad-tasting Bad-tasting

65. Poisonous Mild poison Mild poison Daffodils - nausea, vomiting, cramps and diarrhea Daffodils - nausea, vomiting, cramps and diarrhea

66. Poison hemlock Deadly poison Deadly poison

67. Irritating chemicals Hot peppers Hot peppers have capsaicin have capsaicin

68. Bad-tasting Bitter melon Bitter melon mushrooms mushrooms

69. Parasitism +/- Like very slow predation. A parasite will feed on a host but does not result in immediate death Like very slow predation. A parasite will feed on a host but does not result in immediate death

70. Endoparasites – Live in host Tape worm Tape worm Bacteria Bacteria Liver fluke Liver fluke

71. Exoparasites - External TicksLeechesLampreysmosquitoes

72. Mutualism A cooperative relationship where both species benefit pos/pos A cooperative relationship where both species benefit pos/pos Pollinators Pollinators

73. Mutualism Ex. Acacia trees and fire ants Ex. Acacia trees and fire ants Acacia trees have thorns that secrete nectar Ants protect and defend plant from animals that would eat it

74. Mutualism - pollinators Insects InsectsBirds and others

75. Commensalism (+, 0 ) Benefits one species with little or no effect on the other Benefits one species with little or no effect on the other

76. Commensalism Birds follow army ants to find food Birds follow army ants to find food

77. Cape buffalo The buffalo stirs up the insects and the egrets can then feed on them The buffalo stirs up the insects and the egrets can then feed on them

78. parasitism and mutualism. Aphids are a major plant pest. They such the sap out of the plant and their sweet secretions may cause a heavy growth of sooty mildew on the leaf surfaces. These same aphids are ‘farmed’ by ants. The ants feed on the sugar rich secretions of the aphids, move them to better sites, and protect them from predators. Aphids are a major plant pest. They such the sap out of the plant and their sweet secretions may cause a heavy growth of sooty mildew on the leaf surfaces. These same aphids are ‘farmed’ by ants. The ants feed on the sugar rich secretions of the aphids, move them to better sites, and protect them from predators.

79. Competition (-/+) or (+/-)? Only one organism will win Only one organism will win

80. Competition exclusion One Species is eliminated from a community because of limited resources. Can not occupy same niche One Species is eliminated from a community because of limited resources. Can not occupy same niche

81. Ecological succession 56.5

82. Succession The gradual growth of species in an area The gradual growth of species in an area

83. Primary succession The development of a community in an area that has not supported life previously. The development of a community in an area that has not supported life previously.

84. Primary succession occurs on bare rock, bare rock, After volcanic eruption, After volcanic eruption, sand dunes sand dunes

85. Primary succession Very SLOW – few minerals available can take 100s of years Very SLOW – few minerals available can take 100s of years

86. Stages of primary succession

87. 1) Lichens mutualism between fungi and algae or cyanobacteria. mutualism between fungi and algae or cyanobacteria. Fungi protect, algae provides food by photosynthesis Fungi protect, algae provides food by photosynthesis

88. Acids from Lichens turn rock to soil (chemical weathering)

89. Lichens eventually die and become part of soil Lichens eventually die and become part of soil

90. 2) Mosses Need a little soil. Can also grow on dirty rock Need a little soil. Can also grow on dirty rock

91. 3) Grasses Need thin layer of soil Need thin layer of soil

92. 4) shrubs Need thick layer of soil Need thick layer of soil

93. 5) trees Need established thick soil layer Need established thick soil layer

94. Secondary succession Occurs when an existing community has been cleared such as Occurs when an existing community has been cleared such as forest fire forest fire land slide land slide

95. Climax Community Stable end of succession Stable end of succession High bio diversity High bio diversity High relative abundance High relative abundance

96. Succession summary

97. Eutrophication “good eating” “good eating” The slow process of a lake ecosystem dying due to over growth of algae which kills other plants beneath and then the fish and animal life The slow process of a lake ecosystem dying due to over growth of algae which kills other plants beneath and then the fish and animal life

98. Eutrophication Mostly from pollution – fertilizers, detergents Mostly from pollution – fertilizers, detergents

99. Algae grow on surface from HIGH nutrients, block light to other plants Plants below die Plants below die O 2 decreases O 2 decreases Fish die Fish die

100. Sediment fills in water A stream flowing in can add sediment faster A stream flowing in can add sediment faster

101. Eutrophication of Caspian sea

102. Biodiversity Increases survival of an ecosystem Increases survival of an ecosystem