Before beginning this activity, students should have the following background information:
Whales, seals, dolphins, and porpoises are not fish, but mammals, which means they are warm blooded.
Warm-blooded animals’ body temperatures remain constant; their body temperatures do not adjust to changes in the surrounding temperature.
Warm-blooded animals, in order to maintain a constant body temperature, need a way to keep warm when the surrounding temperature is cold.
2.
Ask students how they think sea mammals—such as whales, seals, dolphins, and porpoises—stay warm in cold water.
3.
Make sure students know what blubber is—a thick layer of fat beneath the skin of sea mammals. Tell them that they are going to do an experiment to find out how blubber helps sea mammals stay warm.
4.
Divide the class into groups, giving each group a large bowl filled with cold water and ice cubes and a rubber glove.
5.
Direct students to take turns putting on the rubber glove and submerging the gloved hand in the ice water for 30 seconds. Have each student tell the group how his or her hand feels after being submerged. (If you wish, have the student insert a thermometer into the glove and wait one minute until the temperature registers.)
6.
Tell students to record each student’s reaction (and optional thermometer reading) on a chart they devise themselves. The chart should have columns for group members’ names and for members’ reactions (and an optional column for thermometer readings) without “blubber.” The chart should also have a column for reactions (and an optional column for thermometer readings) with “blubber.”
7.
Next, have students take turns repeating the procedure, with each group member thickly coating his or her hand with solid vegetable shortening before putting on the glove. Have each student tell the group how his or her hand feels this time. (If using a thermometer to measure the temperature, students should wait until the thermometer registers room temperature again before proceeding with this step.) Group members should add data from this step to their chart.
8.
Discuss results with the class. Why did students’ hands feel warmer when coated with solid vegetable shortening than when uncoated? What does this experiment tell them about the function of blubber in sea mammals?
9.
Have students wash their hands with soap and water after the experiment.
Younger students will need help coating their hands with the shortening and with cleaning up. If students will record data on charts, you might prepare the charts for the students in advance. Rather than have students work on their own, you might have one or more volunteers perform the experiment, with your help, as a demonstration for the class.
Besides blubber, what are some other physical characteristics that help keep animals keep warm in cold climates?
2.
Think of some animals that live in cold climates and some that live in hot climates. Compare and contrast their physical characteristics.
3.
Humans have a layer of fat under the skin, but not enough to keep us warm. How do humans keep warm in cold weather?
4.
Underwater mammals differ in many ways from mammals that live on land. In what ways are land mammals and underwater mammals similar? What common characteristics qualify both groups of animals to be called mammals?
Eight Things about Sharks
Invite students to brainstorm ideas and questions about sharks. Then encourage them to do research to answer any questions they have. Have each student or group of students create a storyboard for a television documentary about sharks. Each student or group should fold a large sheet of paper into eight parts and illustrate or write eight of the important ideas about sharks they would want to show. Students should write captions for all drawings.
Keiko to the Sea
Discovery Channel Online presents this page to showcase information about its stirring video, “Keiko's Story: The Long Journey Home.” This site has additional details about the program that can lead to further research.
Oregon Coast Aquarium
This is the home page of the aquarium where Keiko is living now.
Definition: To become ready for a new situation by changing. Context: Life on this stuff is tough and only tough creatures able to change, or adapt, can survive.
Definition: Animals which are warm-blooded, breath air, and nurse their young. Context: Though they spend their whole lives in water, whales are not fish. They are mammals, like us.
Definition: An action of whales that involves leaping into the air and crashing back onto the water’s surface. Context: Breeching—leaping into the air and crashing back onto the water’s surface—is one of their most common behaviors.
Definition: An animal that hunts one or more other animals for its food. Context: Sharks are very good predators because of their excellent eyesight. Their eyes are sensitive to light and can see the shadows of other fish very easily. Sorry, no sound available.
Definition: A class of animals with common physical features. Context: There are more than 350 different species of sharks, such as the Galapagos shark, the Blue shark, and the very dangerous Tiger shark. Sorry, no sound available.
This lesson plan may be used to address the academic standards listed below. These standards are drawn from Content Knowledge: A Compendium of Standards and Benchmarks for K-12 Education: 2nd Edition and have been provided courtesy of the Mid-continent Research for Education and Learning in Aurora, Colorado.
Grade level: K-2 Subject area: life science Standard:
Knows about the diversity and unity that characterize life. Benchmarks:
Knows that plants and animals have external features that help them thrive in different environments.
