1. AIM: How do interactions between a species and its environment define the species niche. Do Now: What is a species niche? Give an example. HW: Article #1 due Friday End of notes questions

2. Organisms living in each part of an ecosystem differ from eachother.
The environment in one part of an ecosystem is different from the environment in another part.
Organisms living in each part of an ecosystem differ from eachother.
Each organism is adapted to the conditions in the part of the environment in which it lives.

3. The place in an ecosystem where an organism lives
Habitat
The place in an ecosystem where an organism lives
They can be large or small depending on the size of the organism and how much it travels

4. The role of an organism in it’s ecosystem
Niche
The role of an organism in it’s ecosystem
The actions of an organism define it’s niche- a niche is more than an organisms habitat. It’s also what the organism does within a habitat

5. A niche includes both biotic and abiotic factors
Biotic Factors (living things)
Food sources
Predators
Abiotic Factors-nonliving things
Temperature
Sunlight
Water
All of the biotic and abiotic factors taken together define the organisms niche

6. All members of a species are adapted to the same habitat
No two species can share the exact same niche in the same habitat but two species can occupy niches that are very similar
The different species can live side-by-side because they occupy different niches

8. Competitive Exclusion
If two species try to share the same niche, they will compete for resources
One of them will have to move to another area or the population will die out.
The extinction of a population in a specific area due to direct competition with another species for a resource is called competitive exclusion

10. The activity of one species can help define another species niche.

11. Scientist J.H. Connell performed an experiment to study how one barnacle species affects the niche of another
Species A- lives on rocks exposed to air
Species B- lives on rocks covered in water most of the time
He removed all of species B from a small area of the shore
He found that species A began to grow on the lower rocks

13. Cornell hypothesized that species A could live on all parts of the shore, but that species B drove out species A wherever species B can survive.
The A population was limited to the higher rocks by B, even though A could live on all the rocks in the absence of B

14. He hypothesized that the niche of one species can affect the niche of another

15. Fundamental niche = theoretical niche
Niche that an organism can ideally have
(wherever it is able to survive)
Realized niche
The niche that the organism actually has (Where the organism is really living)

17. Niche Diversity The number of different niches in an ecosystem
Determined by the abiotic factors in an environment
Ex:
Marsh- many organisms, few niches
Constant abiotic factors
Desert- few organisms, many niches
Fluctuating abiotic factors

18. Predators
Play an important role in increasing niche diversity by decreasing the population size of their prey
When more resources become available for another species, a new niche will have been created
Predator- actively hunts another organism
Prey- the hunted organism

20. A predator that promotes niche diversity in it’s habitat
Keystone Predator
A predator that promotes niche diversity in it’s habitat

21. What is a species niche?
What factors help to define a niche? Give examples of each.
What prevents two species from sharing the same niche? What is this called?
Explain the difference between an organisms fundamental niche and its realized niche?
What is the role of predators in determining niche diversity?
Identify abiotic factors that contribute to niche diversity.