Learning outcomes:
1 I can describe the effects of extinction and extirpation on biological diversity.
4.1 Reduction of Biological Diversity
The stresses of urbanization and habitat intrusion by farming and
industry has resulted in a decline in _____________________
____________________. Extinction, population decreases and
degradation of ecosystems reduces biological diversity on the Earth.
Extinction:
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Is the __________________ of a species from the entire
planet.
It is a _________________ of the Earth's history.
Scientists estimate ______________ of species that have ever
existed on the Earth are now extinct (many by mass extinction sudden environmental change, like the Ice Age).
Most extinction take place __________________________,
but the rate of extinction is rising, and this is reducing the
biological diversity of our planet.
Ex: Dinosaurs,
__________________:
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is a local extinction, or the disappearance of a species
_____________________________________________.
Ex: the grizzly bear in the Canadian prairies,
Extirpation or extinction
Example
Greater prairie chicken can no more be
found in the eastern prairies
Woolly Mammoth
Grizzly bear in the Californian main land.
Dodo bird
Quagga: half zebra, half horse
Extirpation or extinction
Here is a list of the top 10 extinct species:
http://www.oddee.com/item_88742.aspx
Here is a list of Albertans species endangered and threatened:
http://srd.alberta.ca/fishwildlife/escc/currentlylisted.aspx
Parcs Canada – Endangered species
_________________________ is a slow process. Even if there is a
lot of variation within a species, sometimes the changes in the
environment are so drastic that and so quick, that none of the
individuals within a species can survive. ________________, in the
past, were due to:
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Overspecialization
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Sometimes organisms have adaptations that suit them only to a
very narrow set of environmental conditions. This usually occurs
in a relatively stable area, where the environment does not
change for a very long period of time.
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This is called _______________________and it is another
cause of extinction.
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The ______________________ is a species that is
overspecialized, because it relies on bamboo, making it
vulnerable to extinction, when the bamboo is scarce.
Human Causes of Extinctions and Extirpations
Most extinctions and extirpations today are caused by human activity.
Habitat destruction - as a result of 
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Recovery Mission
 Answer following questions
(Answer on loose leaf in paragraph)
1. How does extinction reduce biological diversity on Earth? Support
your answer using examples and your knowledge.
2. Suppose the deer is extirpated from the Peace River region. In what
way might other organisms be affected? Provide examples to
support your answer.