1. Chapter 5 Biodiversity, Species Interactions, and Population Control

2. Core Case Study: Southern Sea Otters: Are They Back from the Brink of Extinction?
Habitat
Hunted: early 1900s
Partial recovery
Why care about sea otters?
Ethics
Tourism dollars
Keystone species

3. Southern Sea Otter
Figure 5.1: An endangered southern sea otter in Monterey Bay, California (USA), uses a stone to crack the shell of a clam (left). It lives in a giant kelp bed (right). Scientific studies indicate that the otters act as a keystone species in a kelp forest system by helping to control the populations of sea urchins and other kelp-eating species.
Fig. 5-1a, p. 104

4. 5-1 How Do Species Interact?
Concept 5-1 Five types of species interactions—competition, predation, parasitism, mutualism, and commensalism—affect the resource use and population sizes of the species in an ecosystem.

5. Species Interact in Five Major Ways
Interspecific Competition
Predation
Parasitism
Mutualism
Commensalism

6. Most Species Compete with One Another for Certain Resources
For limited resources
Ecological niche for exploiting resources
Some niches overlap

7. Some Species Evolve Ways to Share Resources
Resource partitioning
Using only parts of resource
Using at different times
Using in different ways

8. Resource Partitioning Among Warblers
Figure 5.2: Sharing the wealth: This diagram illustrates resource partitioning among five species of insect-eating warblers in the spruce forests of the U.S. state of Maine. Each species minimizes competition with the others for food by spending at least half its feeding time in a distinct portion (yellow highlighted areas) of the spruce trees, and by consuming somewhat different insect species. (After R. H. MacArthur, “Population Ecology of Some Warblers in Northeastern Coniferous Forests,” Ecology 36 (1958): 533–536.)
Fig. 5-2, p. 106

9. Black-throated Green Warbler Yellow-rumped Warbler
Blackburnian Warbler
Black-throated Green Warbler
Cape May Warbler
Bay-breasted Warbler
Yellow-rumped Warbler
Figure 5.2: Sharing the wealth: This diagram illustrates resource partitioning among five species of insect-eating warblers in the spruce forests of the U.S. state of Maine. Each species minimizes competition with the others for food by spending at least half its feeding time in a distinct portion (yellow highlighted areas) of the spruce trees, and by consuming somewhat different insect species. (After R. H. MacArthur, “Population Ecology of Some Warblers in Northeastern Coniferous Forests,” Ecology 36 (1958): 533–536.)
Fig. 5-2, p. 106

10. Black-throated Green Warbler Cape May Warbler Bay-breasted Warbler
Blackburnian Warbler
Black-throated Green Warbler
Cape May Warbler
Bay-breasted Warbler
Yellow-rumped Warbler
Stepped Art
Fig. 5-2, p. 106

11. Specialist Species of Honeycreepers
Figure 5.3: Specialist species of honeycreepers: Through natural selection, different species of honeycreepers developed specialized ecological niches that reduced competition between these species. Each species has evolved a specialized beak to take advantage of certain types of food resources.
Fig. 5-3, p. 107

12. Insect and nectar eaters
Fruit and seed eaters
Insect and nectar eaters
Greater Koa-finch
Kuai Akialaoa
Amakihi
Kona Grosbeak
Crested Honeycreeper
Akiapolaau
Figure 5.3: Specialist species of honeycreepers: Through natural selection, different species of honeycreepers developed specialized ecological niches that reduced competition between these species. Each species has evolved a specialized beak to take advantage of certain types of food resources.
Maui Parrotbill
Apapane
Unknown finch ancestor
Fig. 5-3, p. 107

13. Most Consumer Species Feed on Live Organisms of Other Species (1)
Predators may capture prey by
Walking
Swimming
Flying
Pursuit and ambush
Camouflage
Chemical warfare

14. Predator-Prey Relationships
Figure 5.4: Predator-prey relationship: This brown bear (the predator) in the U.S. state of Alaska has captured and will feed on this salmon (the prey).
Fig. 5-4, p. 107

15. Most Consumer Species Feed on Live Organisms of Other Species (2)
Prey may avoid capture by
Run, swim, fly
Protection: shells, bark, thorns
Camouflage
Chemical warfare
Warning coloration
Mimicry
Deceptive looks
Deceptive behavior

16. Some Ways Prey Species Avoid Their Predators
Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
Fig. 5-5, p. 109

17. Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(a) Span worm
Fig. 5-5a, p. 109

18. (b) Wandering leaf insect
Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(b) Wandering leaf insect
Fig. 5-5b, p. 109

19. Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(c) Bombardier beetle
Fig. 5-5c, p. 109

20. (d) Foul-tasting monarch butterfly
Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(d) Foul-tasting monarch butterfly
Fig. 5-5d, p. 109

21. Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(e) Poison dart frog
Fig. 5-5e, p. 109

22. (f) Viceroy butterfly mimics monarch butterfly
Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(f) Viceroy butterfly mimics monarch butterfly
Fig. 5-5f, p. 109

23. (g) Hind wings of Io moth resemble eyes of a much larger animal.
Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(g) Hind wings of Io moth resemble eyes of a much larger animal.
Fig. 5-5g, p. 109

24. Figure 5.5: These prey species have developed specialized ways to avoid their predators: (a, b) camouflage, (c–e) chemical warfare, (d, e) warning coloration, (f) mimicry, (g) deceptive looks, and (h) deceptive behavior.
(h) When touched, snake caterpillar changes shape to look like head of snake.
Fig. 5-5h, p. 109

25. (b) Wandering leaf insect
(a) Span worm
(b) Wandering leaf insect
(c) Bombardier beetle
(d) Foul-tasting monarch butterfly
(e) Poison dart frog
(f) Viceroy butterfly mimics
monarch butterfly
(g) Hind wings of Io moth
resemble eyes of a much
larger animal.
(h) When touched,
snake caterpillar changes
shape to look like head of snake.
Stepped Art
Fig. 5-5, p. 109

26. Science Focus: Threats to Kelp Forests
Kelp forests: biologically diverse marine habitat
Major threats to kelp forests
Sea urchins
Pollution from water run-off
Global warming

27. Purple Sea Urchin
Figure 5.A: This purple sea urchin inhabits the coastal waters of the U.S. state of California.
Fig. 5-A, p. 108

28. Predator and Prey Interactions Can Drive Each Other’s Evolution
Intense natural selection pressures between predator and prey populations
Coevolution
Interact over a long period of time
Bats and moths: echolocation of bats and sensitive hearing of moths

29. Coevolution: A Langohrfledermaus Bat Hunting a Moth
Fig. 5-6, p. 110

30. Some Species Feed off Other Species by Living on or in Them
Parasitism
Parasite is usually much smaller than the host
Parasite rarely kills the host
Parasite-host interaction may lead to coevolution

31. Parasitism: Trout with Blood-Sucking Sea Lamprey
Fig. 5-7, p. 110

32. In Some Interactions, Both Species Benefit
Mutualism
Nutrition and protection relationship
Gut inhabitant mutualism
Not cooperation: it’s mutual exploitation

33. Mutualism: Hummingbird and Flower
Figure 5.8: Mutualism: This hummingbird benefits by feeding on nectar in this flower, and it benefits the flower by pollinating it.
Fig. 5-8, p. 110

34. Mutualism: Oxpeckers Clean Rhinoceros; Anemones Protect and Feed Clownfish
Fig. 5-9, p. 111

35. (a) Oxpeckers and black rhinoceros
Figure 5.9: Examples of mutualism: (a) Oxpeckers (or tickbirds) feed on parasitic ticks that infest large, thick-skinned animals such as the endangered black rhinoceros. (b) A clownfish gains protection and food by living among deadly, stinging sea anemones and helps to protect the anemones from some of their predators.
(a) Oxpeckers and black rhinoceros
Fig. 5-9a, p. 111

36. (b) Clownfish and sea anemone
Figure 5.9: Examples of mutualism: (a) Oxpeckers (or tickbirds) feed on parasitic ticks that infest large, thick-skinned animals such as the endangered black rhinoceros. (b) A clownfish gains protection and food by living among deadly, stinging sea anemones and helps to protect the anemones from some of their predators.
(b) Clownfish and sea anemone
Fig. 5-9b, p. 111

37. In Some Interactions, One Species Benefits and the Other Is Not Harmed
Commensalism
Epiphytes
Birds nesting in trees

38. Commensalism: Bromiliad Roots on Tree Trunk Without Harming Tree
Figure 5.10: In an example of commensalism, this bromeliad—an epiphyte, or air plant—in Brazil’s Atlantic tropical rain forest roots on the trunk of a tree, rather than in soil, without penetrating or harming the tree. In this interaction, the epiphyte gains access to sunlight, water, and nutrients from the tree’s debris; the tree apparently remains unharmed and gains no benefit.
Fig. 5-10, p. 111