Blue whales migrate between warm breeding waters and cold feeding waters near Antarctica and in the Arctic. Do you know how whales keep warm when they are in very cold water? They have a thick layer of fat under their skin called blubber. The blubber keeps them warm and also stores nutrients their body can use when they are in waters where there isn't much food. Other marine mammals like seals and sea lions also have blubber.
Do this project to see how blubber can help keep a whale warm in the cold water.
What You Need:
- Container of ice water
- Vaseline or shortening
- 4 ziplock sandwich bags
What You Do:
- Turn one of the ziplock bags inside out and place it inside another bag. Make sure you have the "zippers" lined up correctly so that you will be able to zip the two bags together. Fill the space in between the two bags with a thick layer of shortening or Vaseline, then zip the edges together. This makes a type of glove with an opening for your hand to go in. The fat molecules in Vaseline and shortening make them act a little like blubber.
- Make a "control" glove by putting the other two ziplock bags inside each other. This will you give you the same amount of plastic, but with no insulating "blubber" layer.
- Put your hand in the control glove and stick it in the ice water. Time how long you can keep it there before it gets too cold for you.
- Now put your hand in the glove with the blubber in between the bags and submerge it in the water. Time how long you can keep it there. Can you hold your hand in the water longer?
- Put a thermometer in the control glove and put the end in the water. Record the temperature. Do the same thing with the blubber glove. What is the difference between the two temperatures?
Blubber helps keep animals warm because it acts as an insulator. An insulator slows down the transfer of heat, keeping the animal's body heat from escaping into the water and protecting it from the cold.