LIVING IN THE ENVIRONMENT 17THMILLER/SPOOLMAN

Chapter 5Biodiversity, Species Interactions, and Population Control

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

Southern Sea Otter

Fig. 5-1a, p. 104

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.

Species Interact in Five Major Ways• Interspecific Competition

• Predation

• Parasitism

• Mutualism

• Commensalism

Most Species Compete with One Another for Certain Resources

• For limited resources

• Ecological niche for exploiting resources

• Some niches overlap

Some Species Evolve Ways to Share Resources

• Resource partitioning• Using only parts of resource

• Using at different times

• Using in different ways

Resource Partitioning Among Warblers

Fig. 5-2, p. 106

Fig. 5-2, p. 106

Blackburnian Warbler

Black-throated Green Warbler

Cape May Warbler

Bay-breasted Warbler

Yellow-rumped Warbler

Cape May Warbler

Stepped Art

Blackburnian Warbler

Black-throated Green Warbler

Yellow-rumped Warbler

Bay-breasted Warbler

Fig. 5-2, p. 106

Specialist Species of Honeycreepers

Fig. 5-3, p. 107

Fig. 5-3, p. 107

Fruit and seed eaters Insect and nectar eaters

Greater Koa-finch

Kuai Akialaoa

Amakihi

Kona Grosbeak

Crested HoneycreeperAkiapolaau

Maui Parrotbill Apapane

Unknown finch ancestor

Most Consumer Species Feed on Live Organisms of Other Species (1)

• Predators may capture prey by1. Walking2. Swimming3. Flying4. Pursuit and ambush5. Camouflage6. Chemical warfare

Predator-Prey Relationships

Fig. 5-4, p. 107

Most Consumer Species Feed on Live Organisms of Other Species (2)

• Prey may avoid capture by1. Run, swim, fly2. Protection: shells, bark, thorns3. Camouflage4. Chemical warfare5. Warning coloration6. Mimicry7. Deceptive looks8. Deceptive behavior

Some Ways Prey Species Avoid Their Predators

Fig. 5-5, p. 109

Fig. 5-5a, p. 109

(a) Span worm

Fig. 5-5b, p. 109

(b) Wandering leaf insect

Fig. 5-5c, p. 109

(c) Bombardier beetle

Fig. 5-5d, p. 109

(d) Foul-tasting monarch butterfly

Fig. 5-5e, p. 109

(e) Poison dart frog

Fig. 5-5f, p. 109

(f) Viceroy butterfly mimics monarch butterfly

Fig. 5-5g, p. 109

(g) Hind wings of Io moth resemble eyes of a much larger animal.

Fig. 5-5h, p. 109

(h) When touched, snake caterpillar changes shape to look like head of snake.

(d) Foul-tasting monarch butterfly

(e) Poison dart frog

Stepped Art

(h) When touched,snake caterpillar changesshape to look like head of snake.

(a) Span worm (b) Wandering leaf insect

(c) Bombardier beetle

(f) Viceroy butterfly mimicsmonarch butterfly

(g) Hind wings of Io mothresemble eyes of a muchlarger animal.

Fig. 5-5, p. 109

Science Focus: Threats to Kelp Forests• Kelp forests: biologically diverse marine habitat

• Major threats to kelp forests1. Sea urchins2. Pollution from water run-off3. Global warming

Purple Sea Urchin

Fig. 5-A, p. 108

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

Coevolution: A Langohrfledermaus Bat Hunting a Moth

Fig. 5-6, p. 110

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

Parasitism: Trout with Blood-Sucking Sea Lamprey

Fig. 5-7, p. 110

In Some Interactions, Both Species Benefit

• Mutualism

• Nutrition and protection relationship

• Gut inhabitant mutualism

• Not cooperation: it’s mutual exploitation

Fig. 5-8, p. 110

Mutualism: Hummingbird and Flower

Mutualism: Oxpeckers Clean Rhinoceros; Anemones Protect and Feed Clownfish

Fig. 5-9, p. 111

Fig. 5-9a, p. 111(a) Oxpeckers and black rhinoceros

Fig. 5-9b, p. 111(b) Clownfish and sea anemone

In Some Interactions, One Species Benefits and the Other Is Not Harmed

• Commensalism

• Epiphytes

• Birds nesting in trees

Commensalism: Bromiliad Roots on Tree Trunk Without Harming Tree

Fig. 5-10, p. 111