1. Habitat vs. Niche
Habitat- the place in which an organism lives out its life
Niche - the role a species plays in a community; its total way of life
A niche is determined by the tolerance limitations of an organism, or a limiting factor.
Although several species may share a habitat they each have their own niche. A niche is a very narrow range where a species fits within a habitat.

2. Competitive Exclusion Principle
No two species can occupy the same niche in the same place at the same time.
One species will be eliminated from a community because of competition for the same limited resource.

3. Limiting Factors
Limiting factor- any biotic or abiotic factor that restricts the existence of organisms in a specific environment or causes population growth to decrease.
Most of the time the limiting factor is a resource in insufficient supply.

4. Limiting Factors Examples of limiting factors - Amount of water
Amount of food
Temperature
Amount of space
Availability of mates
Although several species may share a habitat they each have their own niche. A niche is a very narrow range where a species fits within a habitat.

5. Limiting Factors
Density-dependent limiting factor — factor that only limits growth of a population when the population density reaches a certain level (overcrowding).
Examples: food, water, shelter, competition, predation, parasitism, and disease

6. Limiting Factors
Density-independent limiting factors — these limit growth regardless of the population size.
Examples: unusual weather, natural disasters, seasonal cycles, and human activities

7. Resources
Renewable Resources—a resource that can regenerate quickly and that is replaceable.
Examples: sunlight, trees, etc…

8. Resources
Nonrenewable Resources—a resource that cannot be replenished by natural processes.
Example: fossil fuels

9. Competition—interaction in which organisms of the same or different species attempt to use the same ecological resource in the same place at the same time.
Competition

10. Predator/Prey—interaction in which one organism captures, KILLS, and feeds on another organism.
Predation

11. Symbiotic Relationships
Symbiosis- two species living together
3 Types of symbiosis:
1. Commensalism
2. Parasitism
3. Mutualism
Cleaning shrimp

12. = 1 species Type of relationship Species harmed Species benefits
Species neutral
Commensalism
Parasitism
Mutualism
= 1 species

13. Symbiotic Relationships
Commensalism-
one species benefits and the other is neither harmed nor helped
Ex. orchids on a tree
Epiphytes: A plant, such as a tropical orchid or a bromeliad, that grows on another plant upon which it depends for mechanical support but not for nutrients. Also called xerophyte, air plant.

14. Symbiotic Relationships
Commensalism-
one species benefits and the other is neither harmed nor helped
Ex. polar bears and cyanobacteria
You can see here that this polar bear is no longer white.

15. Commensalism
Whale & Barnacles Shark & Remora

16. Symbiotic Relationships
Parasitism-
one species benefits (parasite) and the other is harmed (host)
Parasite-Host relationship

17. Symbiotic Relationships
Parasitism- parasite-host
Ex. lampreys,
leeches, fleas,
ticks, tapeworm,
Not considered predator-prey because goal is not to KILL host

18. Symbiotic Relationships
Mutualism- beneficial to both species
Cleaner Shrimp & Fish
Bee & Flower
The Egyptian plover takes insects from the backs of buffaloes, giraffes and rhinos. The plover has also been observed taking leeches from the open mouths of crocodiles! In this association the plover receives a supply of food and the other animal rids itself of unwelcome pests

19. Egyptian Plover & Crocodile
Mutualism
Egyptian Plover & Crocodile

20. Symbiotic Relationships
Mutualism-
beneficial to both species
Lichen
Fungus +
Bluegreen
Algae
The Egyptian plover takes insects from the backs of buffaloes, giraffes and rhinos. The plover has also been observed taking leeches from the open mouths of crocodiles! In this association the plover receives a supply of food and the other animal rids itself of unwelcome pests