1. Notes Science Tennessee SPI Objective:
Adaptations
Notes
Science
Tennessee SPI Objective:
Analyze structural, behavioral, and physiological adaptations to predict which populations are likely to survive in a particular environment.
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.
Essential Question
How do species adapt their behavior and their
physical structure in order to survive?
Check for Understanding
Identify an organism’s adaptations that enable it to survive and/or thrive in a specific environment.

2. 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).
Mammoths
Dinosaurs
Extinct
Extinct

3. Environments always change over time
One cause of environmental change is Earth’s tilted axis.
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.
Organisms that can not adapt to these seasons will die.
Spring
Summer
Winter
Fall

4. Environments always change over time
Another cause of environmental change
is the movement of tectonic plates.
As part of Pangaea, Antarctica was once further North.
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
Present
Past
Video Link 01 (29 sec): Pangaea-Continental Drift
Video Link 02 (1 min 36 sec): Continental Drift-600 Million Years

5. Environments always change over time
Another cause of environmental change is due to the way the Earth orbits (revolves) the sun.
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.
Distance
These cold periods are called “Ice Ages.”
These warmer periods are called “Inter-glacials.”
As the distance increases or decreases,
the Earth becomes colder or hotter.

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

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

8. Key Idea: Environments always change sooner or later
Quick
Review
SPI
Adaptations
Science
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?
What is extinction?
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.