1. 5.1 Habitats and Niches Ecosystems *Large systems *Cover many miles
*Contain many different species
* The environment within an ecosystem is different depending on where you are.
*The area where a trout lives is different than where a bear lives, but is still the same ecosystem.

2. The place within an ecosystem where an organism lives.
Habitat
The place within an ecosystem where an organism lives.

3. Niche The role of an organism in
the ecosystem and what an
organism does within its
habitat
*Every organism is adapted to life in its habitat
*Each organism has its own way of gathering food, reproducing and avoiding predators
*Includes biotic factors (living parts) which include food sources and predators and abiotic factors (non-living parts) which include sunlight, water, and temperature.
*All members of a species are adapted to a niche
*No two different species can share the same niche but can have similar niches. This is because of competition for resources like food. If 2 different species ate the same food and 1 species was better at getting the food than the other species, the one species not so good at getting the food would die off.

4. Competitive Exclusion
The extinction of a population due to direct competition with another species for a resource. This could also cause one species to be evicted from the niche which would allow survival of both species.

5. Niches Fundamental niche
* The niche that an organism could theoretically occupy.
Realized niche
* The niche that an organism actually occupies which could be less extensive (smaller) than the fundamental niche.
Read p.74 about barnacles

6. Niche Diversity · The number of different niches in an ecosystem.
· Determined by abiotic factors which could make more niches.
· Predators (organisms that actively hunt other organisms
known as prey) increase niche diversity by decreasing the population size of their prey species which allows more resources for other species in that niche.
*Keystone predator is a predator that promotes a great niche diversity in its habitat
*Abiotic factors contribute to niche diversity. These include temperature changes and moisture