Download Ecology

Ecology
Outline
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Niches
Biomes
Plant communities
Ecological levels
Relationships of organisms
Ecology is the study of the interactions that
affect the abundance and distribution of
living organisms.
Habitat and niche
• Habitat is the organisms
“address”
• Niche is the organisms “job”
within that address
Fundamental niche is the total number of
positions that an organism can occupy
Realized niche is the actual position that an organism actually occupies
Biomes are large areas
that have a similar climate
Biomes can be classified by
temperature and precipitation
Biomes are made up of plant communities
Deserts
Oak woodlands
High altitude meadows
provide habitat diversity
within forest biomes
Conifer forests can be
shaped by fire frequency
The coastal interface
provides a wealth of
diversity
Salt marshes are some of
the most productive plant
communities
Plant communities can change along distinct lines
The first level of ecology is individuals
All of the individuals in a
given area constitutes a
population
A variety of populations follow a logistical curve
Human population is expanding exponentially
Communities consist of many
populations interacting together
Food chains are simple
ways of looking at the
relationships of
organisms
Food webs show the
inter-relatedness of
organisms on the same
level of the food chain
Real-life food webs are much more complicated
Herbivory two organisms interacting where
one species benefits and the other is harmed
Leaf-cutter ants
Chiton
Some herbivores can have large effects
on plant communities and ecosystems
Commensalism is the interaction of two organisms
where one species benefits and the other is not affected
Predation is the
interaction of two
organisms where one
species benefits and the
other is harmed
Bird that spears fish
Voracious intertidal predator
In Symbiotic relationships both
organisms benefit
Parasitic relationships the host
suffers and the parasite benefits
Competition is when two organisms suffer as a
result of an interaction. Some organisms suffer
more than others
Possible relationships of
organisms
• Commensal +
• Predation
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• Symbiotic
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• Parasitic
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• Competition • Herbivory
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22,137 species have gone
extinct since 1600 to 1993
This is approximately 100-1000 times
the background rate of extinction
assessed from the fossil record