Chap 5

F. Species Interactions: 1. Competition F. Species Interactions: 1. Competition

a. Intraspecific competition

- same species

b. Interspecific competition

-diff. species same resource

a. Intraspecific competition

- same species

b. Interspecific competition

-diff. species same resource

Fig. 7-8, p. 148

Resource Partitioning of Warbler Species

Resource Partitioning

© Brooks/Cole Publishing Company / ITP

Species with similar resource requirements can coexist because they use limited resources at different times, in different ways, or in different places. For example, specialized feeding niches of various birds of coastal wetland enable coexistenceof many species.

Fig. 9–4a

c. Resource Partitioning and Niche Specialization

Fig. 7-7, p. 147

Species interactions-Symbiosis

Competition

Predation

Parasitism

Mutualism

Commensalism

Research Predation

Parasitism

Mutualism

Commensalism

Invasive species

Native species

Indicator species

Keystone species

Click to view animation.

f. Competitive Exclusion Principle

Gause's competition experiment interaction.

2. Species Interactions: Predation2. Species Interactions: Predation

Predator Predator

Prey Prey

c. Prey acquisition – 2 typesc. Prey acquisition – 2 types

d. Predator avoidanced. Predator avoidance

e. Defensee. Defense

Avoiding or Defending Against PredatorsAvoiding or Defending Against Predators

Escape Escape Senses Senses Armor Armor Camouflage Camouflage

Chemical warfare Chemical warfare

Warning coloration Warning coloration

Mimicry Mimicry

Safety in numbers Safety in numbers

Behavioral strategies Behavioral strategies

Avoidance Defense

Both

Span worm Bombardier beetle

Viceroy butterfly mimicsmonarch butterfly

Foul-tasting monarch butterfly

Poison dart frog When touched, the snake caterpillar changes shape to look like the head of a snake

Wandering leaf insect

Hind wings of io mothresemble eyes of a much larger animal

p. 169How Species Avoid Predators

3. Species Interactions: Parasitism 3. Species Interactions: Parasitism

Parasite Parasite

Host Host

Dangers of parasites Dangers of parasites

Importance of parasites Importance of parasites

4. Species Interactions: Mutualism4. Species Interactions: Mutualism

Pollination Pollination Nutritional Nutritional Gut inhabitantsGut inhabitantsProtectionRhizobium and legumes

ProtectionRhizobium and legumes

a. Examplesa. Examples

5. Species Interactions: Commensalism5. Species Interactions: Commensalism

Species interaction that benefits one and has little or no effect on the other

Species interaction that benefits one and has little or no effect on the other

SymbiosisSpecies 1

Sp.2

+ - 0

+

-

0

Mutualism& Synergism

Predation& Parasitism

Commensalism

Competition

Amensalism Neutralism

APES Chapter 5

Community Ecology Part 2

What is a bee’s niche?

YouTube - NATURE | Silence Of The Bees | Online Exclusive | PBS

Diversity

Succession. Animation.

G. Ecological SuccessionG. Ecological Succession

Process in which communities of plant and animals species are replaced over time by a series of different communities

Enchanted Rock

Lichen-pioneer species

Two kinds of Succession1. Primary succession - begins with a lifeless area where

there is no soil (ex. bare rock). Soil formation begins with lichens or moss.

2. Secondary succession - begins in an area where the natural community has been disturbed, removed, or destroyed, but soil or bottom sediments remain.

1. Primary Succession

1. Primary Ecological Succession

Fig. 7-11 p. 152

Click here for animation

2. Secondary Ecological Succession

Fig. 7-12, p. 153

Succession3. Pioneer species

pioneer community4. Equilibrium species5. Successional species

= pioneer & equilibrium species

6. Climax species climax community

(Nu

mb

er

of

spe

cie

s)

Mechanisms of Succession

© Brooks/Cole Publishing Company / ITP

Both primary and secondary succession are driven by three mechanisms:• facilitation: a process by which an earlier

successional species makes the environment suitable for later successional species; e.g., legumes fixing nitrogen can enable later successional species;

• inhibition: a process whereby one species hinders the establishment and growth of other species; e.g., shade of late successional trees inhibits the growth of early successional trees;

• tolerance: a process whereby later successional species are unaffected by earlier successional species.

6. Effects on Succession and Species Diversity

a. Disturbancea. Disturbance

b. Intermediate disturbance hypothesis

b. Intermediate disturbance hypothesis

Harvester ant mound

1000Percentage disturbance

Sp

ecie

s d

iver

sity

Fig. 7-13, p. 154

6 b. Intermediate Disturbance Hypothesis

7. How Predictable is Succession?

Climax communityClimax community

“Balance of nature”“Balance of nature”

Unpredictable struggleUnpredictable struggle

Ecologists’ viewsEcologists’ views

H. Ecological Stability and SustainabilityH. Ecological Stability and Sustainability

1. Stability1. Stability

2. Inertia2. Inertia

3. Persistence3. Persistence

4. Constancy4. Constancy

5. Resilience5. Resilience

6. Species diversity and ecosystem stability6. Species diversity and ecosystem stability

7. Precautionary principle7. Precautionary principle