Key Concepts: Niches and Habitat

Habitat vs. Niche

• Habitat: The physical place where an organism lives (its "address")
• Niche: The organism's role in its ecosystem (its "job")

Components of a Niche

• What the organism eats and what eats it
• When and where it is active
• How it affects and is affected by other organisms
• Physical conditions it can tolerate

Competitive Exclusion Principle

Two species cannot occupy the exact same niche indefinitely — one will outcompete the other.