1. Extinction
S4L2b. Identify factors that may have led to the extinction of some organisms.

2. Basic needs Animals and plants have basic needs, such as: Water Food
Shelter
Air
When these needs are not met, plants and animals must adapt or die.

3. Extinction
The death of all the members of a certain group of organisms.
Examples: dinosaurs, passenger pigeons, and dodo birds

4. Endangered species
Endangered species have populations so small that they are likely to become extinct if action is not taken.
Examples: whooping cranes, Florida panther, loggerhead turtles

5. Threatened species
Species are likely to become endangered if they aren’t protected
Threatened animals are protected by strict hunting laws
Example: American crocodile

6. Causes of ecosystem changes
Drought or lack of enough rain and water
Fires which can be started naturally or by humans
Disease which can cause living things to die
Overpopulation or when there are more living things than an ecosystem can support
Human Activity

7. Human Activity The major cause of extinction today is human activity.
Loss of habitat is the main reason for animal extinction today. Clearing forests or draining wetlands takes away plant and animal habitats.
Excessive hunting or fishing can cause a species to become endangered or extinct.
Pollution of the land, water and air makes it difficult for animals to live.
The introduction of a new species into an ecosystem can upset the balance

8. Is it too late?

9. Extinction is happening today!
Extinction is happening now.
Humans are the main reason.
Habitat destruction is the primary cause.