2. Tennessee SPI Objective: Analyze structural, behavioral, and physiological adaptations to predict which populations are likely to survive in a particular environment. Notes Science Essential Question How do species adapt their behavior and their physical structure in order to survive? SPI 0807.5.2 Adaptations Instructions for Students 1) Make sure you view this presentation in slideshow mode. 2) If you need help, please communicate with your teacher. 3) If needed, there are videos about how to do this on YouTube. Check for Understanding Identify an organism’s adaptations that enable it to survive and/or thrive in a specific environment.

3. Definition: To adapt means to change in order to survive and/or thrive in a specific environment. Note: Before we investigate HOW organisms adapt, it is helpful to first examine WHY organisms must adapt. Organisms must adapt because… …environments always change over time.  Organisms that can not adapt to these changes die.  If too many individuals die, then the entire species goes extinct.  99% of all species that ever lived have gone extinct (very common). Dinosaurs Mammoths Extinct

4. One cause of environmental change is Earth’s tilted axis. Environments always change over time  In Tennessee, during the summer, North America is tilted towards the sun so the climate is hot.  During the winter, North America it tilted away from the sun so Tennessee’s climate is cold. Summer Winter Spring Fall Organisms that can not adapt to these seasons will die.

5.  As part of Pangaea, Antarctica was once further North. Environments always change over time  It was much warmer, and dinosaurs lived there. What happened? Tectonic plates broke apart and Antarctica moved southwards (continental drift). It became a very cold area. Pangaea Past Present  Another cause of environmental change  is the movement of tectonic plates. Video Link 02 (1 min 36 sec): Continental Drift-600 Million YearsContinental Drift-600 Million Years Video Link 01 (29 sec): Pangaea-Continental DriftPangaea-Continental Drift

6.  Another cause of environmental change is due to the way the Earth orbits (revolves) the sun. Environments always change over time  In reoccurring cycles, the Earth wanders in its orbital path.  When it wanders closer to the sun, the planet gets warmer.  When it wanders away from the sun, the planet gets colder. Organisms must adapt to these warmer or colder conditions or die. As the distance increases or decreases, the Earth becomes colder or hotter. Distance These cold periods are called “Ice Ages.” These warmer periods are called “Inter-glacials.”

7.  Volcanic eruptions can throw millions of tons of ash into the atmosphere which blocks sunlight. Video Link: Volcanic EruptionVolcanic Eruption Environments always change over time The plants, animals, and other organisms have to adapt or die.  Another cause: catastrophic events such as volcanic eruptions.  This affects both plants and animals.

8. Video Link: Asteroid Strike (In the Future?)Asteroid Strike (In the Future?) Video Link: Asteroid Strike (In the Past)Asteroid Strike (In the Past) Environments always change over time  Impacts from large meteorites can throw millions of tons of rock-dust into the atmosphere which blocks sunlight.  Another cause: catastrophic events such as a meteorite impact. The plants, animals, and other organisms have to adapt or die.  This affects both plants and animals.

9. Quick Review  What is extinction? Science SPI 0807.5.2 Adaptations  Describe one event (cause) that makes environments change (effect).  Describe another event (cause) that makes environments change (effect).  Describe yet another event (cause) that makes environments change (effect).  When environmental changes occur, what happens to the organisms that live in the environment?  Is extinction rare or common? Key Idea: Environments always change sooner or later Key Idea: Organisms either adapt to changes or they die. If too many die, the species goes extinct.