1. Pictures of animals on small cards
2. Vegetable Shortening
3. Gloves
4. Alcohol Thermometer
5. Bowls
6. Ice
7. Paper towels
8. Water

It is a good idea to have things set up before the students arrive. The instructor should make place settings at each table for the student to sit at by placing a paper towel at each place. Also have gloves at each table, a container of Crisco, icy water, and extra paper towels. Setting up is easy and should only take about 5-10 minutes.

The experiment will integrate the student’s knowledge of mammals and their thermoregulation by being an active participant in this activity. The experiment is designed to allow students to explore thermoregulation though a hands-on procedure.

1. Divide the group of students into smaller groups (3-4 in a group).
2. Next the two groups will each be given a large bowl filled with water, ice and rubber gloves. The students will be directed to place the ice in the bowl, creating an arctic-ocean environment. The students will wait three minutes for the water to chill. While they are waiting they will be instructed on how to use the student data sheet, which is self-explanatory, and each group will be given a sheet.
3. After the water has chilled, the students will take the temperature of their water and record that data in the appropriate box on the data sheet.
4. The students will then place one glove on either of their hands. They will take turns having one student place their hand in the water for thirty seconds and telling the other students how it feels. For example, does his or her hand feel cold? Does it hurt at all? How do you feel? The other students will record these observations on the data sheet. When everyone has finished experiencing the water temperature they will move onto the next phase.
5. Dry off the wet gloves and then liberally apply vegetable shortening to their gloved hands. A second glove will be added to represent the dermal layer, which covers the insulating blubber of marine mammals. Once again the students will take turns placing their hands in the water for thirty seconds, making observations and recording observations.

Student Data Sheet

During the discussion of the results the students will be engaged in answering questions related to the experiment.

1. What was the difference between the first time their hand was in the water and the second time? Why did it feel different?

Possible responses: The first time there was no insulation….

2. What does this experiment show about the function of blubber?

Possible responses: Blubber acts as an insulator for mammals…

3. Besides blubber, what are some other physical characteristics that help keep animals warm in cold climates?

Possible responses: Fur, hair, behavior, metabolism…

4. Think of some animals that live in cold climates and some that live in hot climates. Compare and contrast their physical characteristics.

For this question the students will be presented again with the pictures of the mammals that were shown to them at the beginning of the station. They will pick a few to discuss.

Possible responses:

Similarities:

Whales/Walrus	Elephant/Tiger
* hair	* hair
* warm blooded	* warm blooded
* fat reserves	* fat reserves
* give birth	* give birth

Differences:

Whales/Walrus	Elephant/Tiger
* sustains swimming and diving for long periods of time	*short bursts of energy
* can’t live away from water	* can’t live in water
* blubber layer	*fat layer

1. Humans have a layer of fat under the skin, but not enough to keep us warm. How do humans keep warm in cold temperatures?

The wrap up will help bring closure to the station while giving the students a chance to review what they have learned. A good way to incorporate this will be to let the students explain in their own words what they have learned while the presenter cleans up the station. If time permits, students will be encouraged to ask any additional questions.

Conclusion
This lesson should teach students the basic principles of thermoregulation. The activity is simple and can be used to demonstrate an important marine mammal adaptation. Blubber plays a very important roll in the lives of marine mammals. It serves as an energy resource during fasting, streamlines the body, and most importantly, acts as an insulator.

There are a few things that can be added onto this activity. First of all, there can be a quick discussion comparing heat loss in water and in air. The following activity can be used to illustrate the concepts behind this:

The presenter will lead into the activity by asking, "Do you think it’s easier to lose heat in water or air?" Then the presenter will perform a demonstration to help show that heat is lost in water more quickly than in air. The demonstration entails taking two 50mL beakers and filling them with hot water. Then the water temperature is measured in both beakers and recorded. One of the beakers is set on the counter at room temperature. The second beaker is placed into another beaker that is filled with water that is at room temperature. An original observation will be made to see which is cooling faster, and then the beakers will be left until the end of the experiment and a final observation will be made. The results will quickly be discussed. If for some reason, results other than what were expected occur, the presenter can ask why that is and reasons for error can be discussed.

Another simple addition to the activity can be used to compare the different ways that marine mammals keep warm. As discussed in the main activity, they can use blubber. But some marine mammals, such as sea otters, need to rely on other means to keep warm. They use their fur. Air gets trapped between their hair and forms tiny chambers of air that help insulate the body. A quick way to add this in would be to get a mitten made of synthetic rabbit fur, or the like, and have the students put that on a hand and submerge it in the water. Have the students determine which type of insulation works better. Do they think that different forms of insulation correspond to what climate the animals live in?