Causes of Extinction

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Teacher Information!
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Necessary materials:
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PowerPoint Guide
“Unintended Consequences: The case of the red-cockaded
woodpecker”—in-class reading
Causes of Extinction
Fish and Wildlife Resources
Students will be able to…
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Discuss factors contributing to
extinction/endangerment
Discuss the Endangered Species Act
Why do some species become extinct or
endangered and others do not?
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Extinction is natural
99% of all species that have ever existed are
extinct.
Species spend about 1 to 10 million years on
earth.
Why do some species become extinct or
endangered and others do not?
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Some species are more vulnerable and less
adaptive
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Specialists
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Require very specific foods
Endemic species
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Occur in only one place on earth
The extinction rate has greatly increased in
the last 10,000 years. WHY?
Golden Toad—1989
Tasmanian Tiger—1936
Pyrenean Ibex—2000
Passenger
Pigeon—1914
PEOPLE are the root cause of the increased
rate of extinction
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HIPPO
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Habitat alteration:
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desertification, deforestation
urbanization, wetland destruction
agriculture, global climate change
Invasive species
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Utilize resources
Outcompete native species
PEOPLE are the root cause of the increased
rate of extinction
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HIPPO
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Pollution—probably less of a threat than other factors
Population growth (human)
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Exacerbates other factors
Overexploitation
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Hunting
Resource consumption
Endangered Species Act (1966)
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Led to the creation of the “Endangered Species List”
Positive effects
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Recovery & removal (delisted) from the Endangered
Species List
American alligator, peregrine falcon, bald eagle, brown
pelican, gray wolf, gray whale
Endangered Species Act (1966)
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What are the negative effects of the ESA?
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Read : “Unintended Consequences: The Case of the
Red-Cockaded Woodpecker”
Why would land users not want endangered species in
an area?
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“Shoot, shovel, and shut up” principle
Review
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Discuss factors contributing to
extinction/endangerment
Summarize the Endangered Species Act
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