1. Community Ecology
Chapter 37.1 – 37.6

2. What you need to know! The community level of organization
The role of competitive exclusion in interspecific competition
The impact of keystone species on community structure.
The symbiotic relationships of parasitism, mutualism, and commensalism

3. Community
All the organisms of various species that live close enough to interact
4 characteristics:
Species diversity: variety of species
Species richness = total number of species
Species abundance = the amount of each species
i.e. Community 1: 25 A 25 B 25 C 25 D
Community 2: 97 A 1 B 1 C 1 D
Dominant Species: typically most abundant species
Response to disturbance: ecological succession
Trophic structure: energy, feeding relationships, nutrient cycles

4. Interspecific Competition
Competition between species for resources that share the same habitat
Predators competing for prey
Plants competing for soil
Habitat: where the organism lives
Niche: what the organism does in its habitat
Competitive exclusion principle: no two species can occupy the same niche in the same habitat at the same time
Resource partitioning is when organisms live in different regions of the same habitat so they can coexist (realized niche)

5. Predator and Prey
Keystone species exert strong control of an ecosystem
Keystone predators tend to reduce the population of the strongest prey species
This provides an opportunity for lesser species to find niches within the habitat
Unique adaptation:
Camouflage developed as a result of predation
Chemical defenses are common among dangerous prey
Batesian mimicry is when something harmless looks like something harmful
Müllerian mimicry is when two harmful species look similar

6. Symbiosis
Close relationships that develop through coevolution (evolving together)
3 types
Mutualism: both species benefit
Commensalism: one species benefits
Parasitism: one species benefits the other is harmed

7. Which one? http://www.naturefootage.com/video_clips/NZ47_018
animals/ants-and-termites/ant_caterpillarsymbiosis.html