SPI Adaptation SPI Variation Environments always change over time Example: Antarctica is very cold and icy today since it is at the south pole. Press the Right Arrow Button to Advance through the Presentation!  So organisms must also change in order to survive  One reason that environments change is due to the movement of tectonic plates It moved south riding on a tectonic plate. As it moved the environment became colder. Yet millions of years ago Antarctica was further north and had a warm climate. As the environment became colder, the plants and animals there had to adapt or die. Notes  They change seasonally and sometimes for other reasons

SPI Adaptation SPI Variation Environments always change over time It moved south riding on a tectonic plate. As it moved the environment became colder. Millions of years ago Antarctica was further north and had a warmer climate. Antarctica As the environment became colder, the plants and animals there had to adapt or die. Notes

SPI Adaptation SPI Variation Environments always change over time It moved south riding on a tectonic plate. As it moved the environment became colder. Millions of years ago Antarctica was further north and had a warmer climate. Notice that it is moving southward As the environment became colder, the plants and animals there had to adapt or die. Notes Antarctica Video Link: Tectonic Plate MovementTectonic Plate Movement

Sun Earth SPI Adaptation SPI Variation Environments always change over time 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.  Another reason that environments change is due to the way the Earth orbits (revolves) the sun Notes 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. Distance As the planet becomes hotter or colder, plants and animals must adapt or die. As the distance increases or decreases between the Earth and the Sun, Earth becomes colder or hotter.

SPI Adaptation SPI Variation Environments always change over time 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.  Another reason for this change is due to catastrophic events like volcanoes and/or objects striking the planet from space. Notes Video Link: Volcanic EruptionVolcanic Eruption

SPI Adaptation SPI Variation 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. Notes 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 Future?)Asteroid Strike (In the Future?) Video Link: Asteroid Strike (In the Past)Asteroid Strike (In the Past)

Notes SPI Adaptation SPI Variation 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 Adaptation SPI Variation Questions  What is one reason that environments 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.