1. Niches and Community Interactions
4.2
Niches and Community Interactions

2. Niche = range of physical and biological conditions in which a species lives and the way the species obtains resources
Competitive exclusion principle = no two species can occupy the same niche at the same time

4. Species Interactions
1. Predator-Prey  predator hunts, kills, eats prey

5. 2. Herbivore-Plant  herbivores affect size and distribution of plant populations
3. Keystone species  change in its population dramatically changes community

6. Symbiosis: 3 main classes
- Mutualism  both species benefit
- Parasitism  one species (parasite) lives in/on another (host) causing harm
- Commensalism  one species benefits, other is unaffected