ANIMAL ADAPTATIONS Inspired by Art to Zoo: Exploring Animal Natures

A science experiment prepared by Janey Cohen, SBMA Science Consultant

ADAPTATIONS All organisms have adaptations that help them survive and thrive in their particular habitat. Some adaptations are structural. Structural adaptations are physical features of an organism like the large ears on an elephant, the razor-like teeth of the moray eel, or the thick fur on a bear.

Other adaptations are behavioral. Behavioral adaptations are the things organisms do to survive. For example, the singing of humpback whales and the migration of monarch butterflies are behavioral adaptations. Adaptations are the result of evolution. Evolution is a change in a species over long periods of time. Adapta- tions occur because a gene mutates or changes by accident. Sometimes these changes can help an animal or plant survive better than others in the species without the mutation. Those creatures with the best adaptations will generally live longer and produce more offspring. They are said to be the “most fit” for their environment.

HANDS-ON EXPERIMENT: BLUBBER MITTENS • How do marine mammals stay warm in icy waters? • Science Level: all • Purpose: to experience what it is like having the adaptation of an insulating layer of blubber

MATERIALS NEEDED Crisco or lard A large spoon Two zip lock bags, sandwich or larger size A bowl of ice water with ice cubes

PROCEDURE 1. Fill one of the zip lock bags about 1/3 full of shortening. Be careful not to get any on the zipper part of the bag. 2. Turn the other bag inside out. Place it carefully inside the bag with the shortening so that you are able to zip the two bags together. Now you have a “blubber mitten”! 3. Put your bare hand in the ice water. Note how cold it feels! You can also check the temperature with a thermometer. (Warning - Don’t leave your bare hand in the ice water for too long, or it will start to hurt!) 4. Dry your hand and place it in the blubber mitten. You can move the shortening around so that your hand is well insulated with “blubber”. Place your hand in the ice water. Note how cold it feels now. 5. Compare the difference between placing your bare hand in the water and your insulated hand in the water. DISCUSSION How long do you think you could leave your hand in the water if you were wearing the blubber mitten? How long without the mitten?

How does having blubber help marine mammals survive in their habitats?

Can you name some animals that have a layer of fat or blubber?

Can you think of any other ways having a layer of blubber might help an animal survive?

This insulation is essential for the survival of ocean-dwelling mammals. Mammals are warm-blooded, meaning their body temperature stays about the same no matter what the temperature outside is. Keeping a warm body temperature in cold water requires more energy than keeping a warm body temperature in warm water. To insulate the marine mammal, blood vessels in blubber constrict, or get smaller, in cold water. Constricted blood vessels reduce the flow of blood, thus reducing the energy required to heat the body. This conserves heat. Some marine mammals also have a thick fur coat to insulate them.

Whales, dolphins, walruses, and seals all have layers of fat that allow them to stay warm in the cold water. Whales have the thickest layers because they do not have fur on the outside of their bodies. Some whales have blubber up to one foot thick.

Blubber also stores energy and increases buoyancy. Energy is stored in the thick, oily layer of blubber. The energy stored in blubber includes both proteins and fats. The ability of blubber to use these stored nutrients means marine mammals are not forced to search for food for long periods of time. Nursing mothers, for in- stance, build up thick stores of blubber before giving birth. In addition to feeding offspring, mothers cannot regularly search for food. They rely on the energy stored in their blubber. Finally, blubber helps marine mammals stay buoyant, or float. Blubber is generally less dense than the ocean water surrounding it.

EXTENSIONS Try other substances or materials in place of the shortening to compare insulating effectiveness: • Peanut Butter • Styrofoam Peanuts • Sand • Jello • Other ideas students may think of! ANIMAL ADAPTATIONS Inspired by Art to Zoo: Exploring Animal Natures

A science experiment prepared by Janey Cohen, SBMA Science Consultant

HANDS-ON EXPERIMENT: DUCK FEATHERS • How do ducks stay afloat? How can oil spills affect a duck’s feathers? • Science Level: Grades 4 – High School • Purpose: to observe duck feathers and understand why they are water repellent; to see how crude oil adversely affects this adaptation

MATERIALS NEEDED Duck feathers Cotton balls Vegetable oil Water Eyedroppers Three clear plastic cups filled with room temperature water A tub of water with a sheen of oil on top, representing an oil spill

PROCEDURE - PART ONE: WHY DO DUCKS FLOAT? 1. Take three cotton balls to represent three ducks. Take three clear cups filled with room temperature water 2. The first cotton ball will be dry. This represents a duck that has not preened its feathers with its oil gland. Predict what will happen when we place it in the water. Place the cotton ball on top of the water. Observe what happens. 3. Take the second cotton ball. Dip the bottom half in oil. This represents a duck that has preened the bottom feathers with oil. Predict what will happen when we place it in the water, and then place it in the water. Observe what happens. 4. The third cotton ball will represent a duck that coats all of its feathers with oil from its oil gland. First dunk the cotton ball in oil, and then predict what will happen when you place it in the third cup. Place it in the third cup. Observe what happens.

PROCEDURE - PART TWO: HOW DO OIL SPILLS AFFECT DUCKS? 1. Now take a duck feather and look at it carefully through a hand lens. 2. Duck feathers are naturally waterproof, but to maintain this, each feather must be aligned properly so that water cannot seep through the microscopic barbs and barbules that are part of the vane of each feather. These barbs and barbules hook together like Velcro to form a tight waterproof barrier. Each properly aligned feather overlaps another like the shingles on a roof to create an entire waterproof covering for the bird. It is the duck’s job to maintain its feather structure. While preening, ducks distribute natural oils, which help in the long-term maintenance of feathers by keeping the feathers supple so alignment can be maintained. 3. Test that this feather is waterproof by adding a few drops of water with an eyedropper. 4. Now dip the feather for about one minute in the “oil spill”. Observe the feather through the hand lens again. Note how the structure of the feather has changed 5. Test to see if the feather is still waterproof.

DISCUSSION Why are ducks normally waterproof? How did the oil spill affect the duck feather? What affect could these changes have on normal bird activity? What other effects could an oil spill have? What other wildlife species could be affected by an oil spill? What are some of the ways oil gets into our water systems? Do we have to choose between oil and birds? Are there trade offs? What are some alternative energy sources to oil?

EXTENSION Clean the feather with detergent, rinse it in water and dry it. Ob- serve it under the hand lens. Discuss any changes you see and what effect these changes could have on normal bird activity.

Adapted from “No Water Off a Duck’s Back,” Project WILD Curriculum and Activity Guide