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15 Cards in this Set
- Front
- Back
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Dispersal
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Populations tend to spread from one location to another.
May be passive or active. Sometimes happens in response to limited resources. |
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Passive dispersal
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Wind, water current, etc.
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Active dispersal
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Under control of organism: running, walking, swimming, flying.
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Dispersal Specifics
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May involve dispersal of emryos (seeds, spores, eggs), larval or juvenile life stages.
Effective ways to populate new regions or acquire resources. Examples: dandelions; apple seeds; barnacle larvae. |
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Physical Dispersal barrier
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Mountains, valleys, large bodies of water.
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Habitat specificity and behavior dispersal barrier
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Forest versus grassland inhabitants.
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Climatic variation dispersal barrier
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Arctic & Antarctica are similar but divided by tropical & temperate climate regions.
Different fauna at different poles. |
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Human dispersal
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Few barriers limit human dispersal.
Space & water. |
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Earth’s Carrying Capacity
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Based only on food = 7-8 billion people.
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Human Population Growth
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Agriculture & Inustrial Rev have fueled rapid pop expansion.
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Global resource distribution
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Food resources are not equally distributed across globe.
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Malnourished
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Wrong food.
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Undernourished
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Not enough food.
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Ecological footprint
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US residents have large footprint, but not big enough ecological capacity (resource deficit).
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Mexico’s Population
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Mexico has big growth rate due to much youth.
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