What Causes Extinction?
1. To introduce the topic of endangered species, list 3-6 extinct animals on the board. Ask: What do these animals have in common? After a brief discussion, reveal that all of them are extinct. Invite students to name other animals that are now gone forever. Possible responses: dinosaurs, woolly mammoths, trilobites.
2. Ask: What percent of animal species that have ever lived are now extinct? Encourage students to make a prediction, and give the reason behind their guess. Write all predictions on the board. Reveal the answer: over 99% of all species that have ever lived are now extinct. (You may also discuss how we know about species that lived millions of years ago. Answer: fossils.)
3. Ask students to brainstorm: What are some reasons animal species become extinct? Write all suggestions on the board. Then discuss the following causes of extinction:
- Outer Space Collision (asteroid)
- Habitat Loss/Pollution
- Global Climate Change
- Invasive Species
4. Distribute the “Causes of Extinction” Student Organizer (PDF) (RTF) and briefly discuss each of the five causes listed on this page. They will be returning to the critical thinking questions on this organizer in the Culminating Activity.
As they learn about endangered animals in this lesson, they can find out which of these causes contributed to each animal population’s decline.
1. FRAME the video segments the students are about to see. Explain that the students will be watching segments from a Nature episode called The Loneliest Animals, about several animal species that are on the brink of extinction. If humans don’t take action soon, these species will be gone forever.
2. Distribute the “Last of Their Kind?” Student Organizer to each student. Provide a FOCUS for the students, asking them to determine the information in the chart and to fill it in as they watch each segment. PLAY at least two of the video segments #1-4 for the class, FOLLOWING UP each segment with a discussion of the challenges faced by each species. Use the provided Answer Key (PDF) (RTF) to answer student questions.
3. Lastly, FRAME segment 5, “Imperiled Lives,” for the students by explaining that this last segment will reveal some new developments in the survival plans for each of the species the students have seen. It will also raise the question of why saving endangered species is important not only to the animals in question, but to humans and the rest of life on earth, as well. PLAY the segment, and FOLLOW UP with a discussion about the importance of saving endangered species.
1.Divide class into pairs or small groups. Have each group or pair select one of the following animals from the program.
- Yangtze giant soft-shelled turtle
- Sumatran rhino
- Golden-crowned Sifaka, and other Madagascar lemurs
- Black-footed ferret
3. Then have students use Web sites listed in the Media Resources section and other library resources to research more information about one of these endangered animal species. By looking at the press releases and blogs of the conservation organizations from the program, kids can become experts on the recent updates about a particular species, and feel a sense of ownership about this animal. To help students organize their research, hand out the “Explore a Species “Student Organizer (PDF) (RTF) to each student for this activity.
4. Once students have gathered all their information, their job is to present this research in the form of a short TV news segment, about five to ten minutes long, with each student having an opportunity to speak before the class. Encourage each group to include photographs and video clips (via Web sites) in its presentation. The presentation should summarize the pros and cons of trying to save this animal species, and include some questions raised during their research.
5. As homework, have students return to the “Causes of Extinction” Student organizer and write a 1-page response to the three critical thinking questions on the organizer. They should include the knowledge they have gained from the examples viewed and researched in class.
Conduct a hands-on activity to demonstrate how habitat destruction can contribute to species extinction. Refer to the “Loneliest Animals Extinction Simulation” (PDF) for detailed instructions and a materials list for this outdoor or indoor activity.
Endangered Species in your state:
Have students research endangered species in your region and/or state using resources like the Sierra Club Endangered Species Map and About.com’s Endangered Species in Your State. To find out more about species survival efforts happening near you, contact your local Department of Environmental Protection, a local chapter of the U.S. Fish & Wildlife Service, and/or the zoos and aquariums in your region.