Introduction into Ecology
Ecology Defined
.
Ecology is
the study of
organisms
and their
interactions
with the
environment.
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Levels of Organization
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Types of Ecology
Ecologist use observations & experiments to test
explanations for distributions and abundance of
species.
1. Organismal ecology is the study of physiology and
behavior interacting with environmental challenges
2. Population ecology studies the factors impacting the
number of individuals of a species in an area
3. Community ecology is the study of how organisms
interact with each other and the environment
4. Ecosystem ecology studies the energy flow and
chemical cycling in a given area
Abiotic and Biotic Interactions:
The 1st Law of Thermodynamics
http://www.sci.uidaho.edu/scripter/geog100/lect/16-ecosystems-biomes/ecosystems-files/ecosystems.htm
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Earth’s Climate Varies By Latitude & Season
And Is Changing Rapidly
Macroclimate
consists of patterns on
the global, regional,
and landscape level
Microclimate consists
of very fine patterns,
such as those
encountered by the
community of
organisms underneath
a fallen log
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Earth’s Climate Varies By Latitude & Season
And Is Changing Rapidly
• Seasonal variations of light and temperature
increase steadily toward the poles
• Seasonality at high latitudes is caused by the tilt of
Earth’s axis of rotation and its annual passage
around the sun
• Belts of wet and dry air straddling the equator shift
throughout the year with the changing angle of the
sun
• Changing wind patterns affect ocean currents
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•
Earth’s Climate Varies By Latitude & Season
And Is Changing Rapidly
• Global Climate Change
• Changes in Earth’s climate can profoundly affect
the biosphere
• One way to predict the effects of future global
climate change is to study previous change
• As glaciers retreated 16,000 years ago, tree
distribution patterns changed
• As climate changes, species that have difficulty
dispersing may have smaller ranges or could
become extinct
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Homeostasis
• Organisms must maintain homeostasis, a steady-state
internal environment, despite changes in the external
environment.
• Organisms respond to abiotic factors in 1of 2 ways:
1. Regulators maintain a nearly constant internal
environment, despite external conditions
2. Conformers allow internal environment to vary
- This occurs in organisms whose environments
remain relatively stable