Transcript Notes SPI 0807.5.2 Adaptation SPI 0807.5.3 Variation Environments

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Adaptation
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Environments always change over time
 They change seasonally and sometimes for other reasons
 So organisms must also change in order to survive
 One reason that environments change is due to the movement
of tectonic plates
Example: Antarctica is very cold and
icy today since it is at the south pole.
Yet millions of years ago Antarctica was
further north and had a warm climate.
It moved south riding on a tectonic plate.
As it moved the environment became colder.
As the environment became colder, the
plants and animals there had to adapt or die.
Notes
SPI 0807.5.2 Adaptation
SPI 0807.5.3 Variation
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Environments always change over time
Millions of years ago Antarctica was
further north and had a warmer climate.
It moved south riding on a tectonic plate.
As it moved the environment became colder.
As the environment became colder, the
plants and animals there had to adapt or die.
Antarctica
Notes
SPI 0807.5.2 Adaptation
SPI 0807.5.3 Variation

Environments always change over time
Millions of years ago Antarctica was
further north and had a warmer climate.
It moved south riding on a tectonic plate.
As it moved the environment became colder.
As the environment became colder, the
plants and animals there had to adapt or die.
Notice that it is moving
southward
Antarctica
Video Link: Tectonic Plate Movement
Notes
SPI 0807.5.2 Adaptation
SPI 0807.5.3 Variation
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Environments always change over time
 Another reason that environments change is due to the way the
Earth orbits (revolves) the sun
Example: In reoccurring cycles lasting thousands to millions of years, the Earth
wanders either a bit further away or a bit closer to the sun as it orbits the sun.
When Earth orbits closer to the sun, the entire planet is warmer. When Earth orbits
farther away from the sun, the entire planet gets colder.
As the planet becomes hotter or colder, plants and animals must adapt or die.
Earth
As the distance increases or
decreases between the Earth
and the Sun, Earth becomes
colder or hotter.
Sun
Notes
SPI 0807.5.2 Adaptation
SPI 0807.5.3 Variation
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Environments always change over time
 Another reason for this change is due to catastrophic events
like volcanoes and/or objects striking the planet from space.
Example: Volcanic eruptions can throw tons and tons of rock dust and smoke into the
atmosphere creating gigantic clouds that block sunlight making the Earth colder and
hurting plants.
Video Link: Volcanic Eruption
Notes
SPI 0807.5.2 Adaptation
SPI 0807.5.3 Variation
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Environments always change over time
 Another reason for this change is due to catastrophic events
like volcanoes and/or objects striking the planet from space.
Example: When large asteroids strike the Earth, rock is pulverized and similar to
volcanic eruptions, tons of rock dust is thrown up into the atmosphere. These dust
clouds block sunlight causing our planet to become colder and hurting plants.
Video Link: Asteroid Strike (In the Past)
Video Link: Asteroid Strike (In the Future?)
Notes
SPI 0807.5.2 Adaptation
SPI 0807.5.3 Variation
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Environments always change over time
 So organisms, both plants and animals, must also change
 Changing is called adapting (also called adaptation)
 If an organism can not adapt to environmental changes they die
 If too many of the organisms die, then the entire species will
go extinct
Quick
Review
SPI 0807.5.2 Adaptation
SPI 0807.5.3 Variation
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Questions
 What is one reason that environments change?
 What is another reason that environment change?
 What is another reason that environment change?
 When environmental change occurs, what happens to the
organisms that live in the environment?
 What is extinction?
 Is extinction rare or common?
 Explain how humans are causing environmental change
around the planet.