Download 14.1 Habitat And Niche

14.1 Habitat And Niche
KEY CONCEPT
Every organism has a habitat and a niche.
14.1 Habitat And Niche
A habitat differs from a niche.
• A habitat is all aspects of the area in which an organism
lives.
– Ex:
biotic factors
abiotic factors
14.1 Habitat And Niche
• An ecological niche includes all of the factors that a
species needs to survive, stay healthy, and reproduce.
– Ex:
Food
abiotic conditions
behavior
14.1 Habitat And Niche
Resource availability gives structure to a community.
• Species can share habitats and resources.
• Competition occurs when two species use resources in the
same way.
• Competitive exclusion keeps two species from occupying
the same niche.
– One species is better suited to the niche and the
other will either be pushed out or become extinct.
14.1 Habitat And Niche
• Competitive exclusion has different outcomes.
– The niche will be divided.
– The two species will further diverge.
14.1 Habitat And Niche
Competitive Exclusion
• 1934: G.F. Gause
• Observed two paramecia: Paramecium aurelia
and Paramecium caudatum
14.1 Habitat And Niche
Competitive Exclusion
• Separate they survived
• Together Paramecium aurelia
thrived Paramecium caudatum
died
• Inferred that one species was
better adapted to take advantage
of limited resources and
prevented the other from doing
the same.
14.1 Habitat And Niche
Niche Partitioning
• Grew two other species of protists in the same flask and
observed these species separating from each other.
• One species lived exclusively in the medium while the
other species lived on the flask’s walls
• Observed niche partitioning.
14.1 Habitat And Niche
Niche Partitioning
Intertidal Zone
14.1 Habitat And Niche
• Ecological equivalents are species that occupy similar
niches but live in different geographical regions.
Madagascar
South America
14.1 Habitat And Niche
Crash Course
• Community Ecology: Feel the Love - Crash Course
Ecology #4
https://www.youtube.com/watch?v=GxE1SSqbSn4&index=4
&list=PL8dPuuaLjXtNdTKZkV_GiIYXpV9w4WxbX