Download Intro to Ecology

What is Ecology?
• Defined: Studying how life interacts within the
biosphere is called Ecology
• All life interacts within the biosphere
– Area within the deepest ocean trenches to the
highest mountains
Populations
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information box
• Defined: Group of one species living in the same area
• Population changes based on:
– Births, Deaths, Immigration, Emigration, Available resources
Population Patterns
• Populations go
through 3 stages:
1) Slow growth
• Population is slowly
adapting to particular
environment
2) Exponential growth
• High birth rates due to
abundant resources
3) Carry capacity
• Defined: greatest
number of individuals that
the environment can
sustain
• Birth & death rates
eventually balance
• What stage is the
human population in?
What happens once we reach Carrying Capacity?
Some populations stabilize for the
long term
Some populations experience a sharp
decline called a “crash”
Which will humans experience?
Communities
• Defined: Populations of many species living in the same
area at the same time
• Each organism has it own HABITAT
– Habitat: Place where an organism lives
• Each species has its own NICHE
– Niche: The role/needs of a species
– Ex: Termites return nutrients to the soil
Ecosystems
• Defined: Communities of species interacting with the living
& non-living
• Biotic (living) Factors:
o Animals: Mice, Reptiles, Insects
o Plants: Cactus, Flowers, Shrubs
• Abiotic (non-living) Factors:
o Sand, rocks, sunlight, climate, soil, water, etc…
• Ecosystem changes affect biodiversity
o Keystone species greatly alter ecosystems
What is a Biome?
• Defined: Large
area with
distinct
climate, plant,
and animal life
• Climate
factors: sun,
rain,
topography
• Climate
determines
life
• Defined: All
organisms
and the part
of the Earth
where life
exists
• Biosphere
changes can
affect life
• Ex: More CO2
in the
atmosphere…
causes
warmer
temps
The Biosphere
Review
1) What is ecology?
2) What are two reasons that populations will increase?
3) What are two reasons that populations will decrease?
4) What are factors that control population growth called?
5) How does a population, community, ecosystem, biome,
and biosphere differ?
6) What is a keystone species?
7) Place the levels of ecology in order from smallest to largest.
– Ecosystem, Population, Biosphere, Community, Biome