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Kings of Camouflage

Viewing Ideas


Before Watching

  1. Show students the images of the cuttlefish and its parts. Have students describe the animal's physical features and explain how the animal is well adapted to its environment. (Visible external features include being soft bodied and featuring tentacles, flat fins around the body, and large eyes. Features that help it survive in its environment include skin capable of changing color; suckers on tentacles to hold prey; a beak to subdue prey and defend against predators; a large brain to process information and respond to the environment; an internal plate-like cuttlebone to help control buoyancy; an ink sac to create confusion; and fins that allow a great degree of mobility). Which animals do students think are most closely related to cuttlefish and why? (The animals most closely related are the octopus, squid, and nautilus.) On the board, write the classification scheme for cuttlefish:

    Kingdom: Animalia
    Phylum: Mollusca
    Class: Cephalopoda
    Order: Sepiida
    Family: Sepiidae
    Genus: Sepia
    Species: about 120 have been identified

    Assign student teams a classification grouping and have teams research their grouping's definition and the characteristics of cuttlefish that place them in that group. You may want to extend this to having students also classify the octopus, squid, and nautilus to see at what level they diverge, or to classify other ocean-dwelling organisms such as sea stars, sharks, coral, or bony fish.

  2. Cuttlefish use camouflage. Have students define camouflage. Then have them brainstorm examples of camouflage in nature. Record their ideas on the blackboard. When students are finished brainstorming, have them look at their examples and, from them, determine patterns of different types of camouflage. (Some patterns they notice might include producing a color change [cuttlefish, chameleon], having designs or patterns that hide individuals [zebra patterns hide masses of zebras to colorblind lions because you don't see individuals], having the appearance of something predators do not eat [walking sticks], and resembling an organism or an object in order to hide from predators [the viceroy butterfly looking like the monarch butterfly, which is poisonous to birds; fishes that look like seaweed].) Ask students how natural selection plays a part in the evolution of these types of camouflage. Have students explain how each camouflage type provides a selective advantage for the animal. (Protective coloration helps animals hide from predator and prey. In nature, physical features, such as camouflage, that help an animal's survival also increase its chance of reproducing and passing the trait on to the next generation.)

  3. Organize students into four groups. As students watch the program have them take notes on the following topics: characteristics of the cuttlefish, species of cuttlefish and their habitats, methods scientists use to learn about cuttlefish intelligence, and mating rituals.


After Watching

  1. Have student groups that took notes on the same topic meet and then share their notes with the class. Students should summarize the important points of the topics they followed and present those to the class.

  2. Scientists in the program discovered that flamboyant cuttlefish walk around on the ocean floor visible to predators, and they have poisonous muscle tissue. Animals with toxins can be grouped as venomous or poisonous . Venomous organisms deliver toxin to prey by biting or using a stinger, fang, or other specialized body part. Poisonous animals only cause illness or death for predators when they are eaten. Draw a chart on the board similar to the one below but list only the organisms and the headings. Assign groups specific animals to research, and then have groups complete the chart and share information. Have students consider what advantages being poisonous versus venomous (or vice-versa) might have for each animal.

    Animal

    Poisonous or venomous

    Location of toxin on body

    Animal for which it is toxic

    Habitat

    Flamboyant Cuttlefish

    poisonous

    muscle tissue

    large fish

    ocean near Australia and Indonesia

    Black Widow Spider

    venomous

    injects venom by biting

    beetles, grasshoppers, other insects

    protected places—under rocks, dense plant growth; throughout U.S., parts of Canada

    Blue-Ringed Octopus

    venomous

    either bites or secretes saliva near prey

    shrimp

    ocean, in shallow reefs from Japan to Australia

    American Toad

    poisonous

    glands on the skin

    fox

    grasslands, meadows throughout the U.S. as far west as South Dakota

    Komodo Dragon

    venomous

    bites

    deer, birds, snake, fish

    savannah and grasslands on four east islands of Indonesia



  3. In the program, scientists devise tests to measure the intelligence of the cuttlefish. Have students develop a test for learning or conditioning for an animal such as a bird, dog, cat, or fish. Work through a sample test idea together as a class. Help students understand that a good question is one that is testable (i.e., "Can dogs hear low-frequency sound?" would work while "Do dogs like boys better than girls?" would not). Write a question on the board that the class has agreed on. Next, have students brainstorm a materials list, a procedure, and the experimental design.

    After completing the sample, organize the class into teams. Have each team identify a question to test and consider what kind of investigation would be needed to answer the question. Ask students to consider the following as they identify their question:

    • all the variables involved in the question being tested
    • number of trials needed
    • animals and equipment needed
    • where the tests will take place
    • length of the investigation
    • ethical treatment of animals during testing

    Each team should choose a question, brainstorm experiment ideas, and write a procedure for their experiment similar to the one modeled in class. Ask teams to share their experiment ideas with the rest of the students, who will be serving as panel members for a funding agency. The students hearing the proposal should consider whether they think it is worthwhile to fund. They should judge factors that include whether the proposed experiment seems doable, whether its results would answer the question posed, and whether it calls for the ethical treatment of animal subjects. Below is a sample of what a team's final write-up might look like.


    Question: Will goldfish swim to a light that appears before a food reward appears?

    Materials

    • flashlight
    • fish food
    • 5-gallon tank holding 2-4 goldfish

    Procedure

    1. Set the goldfish tank in a quiet area.

    2. At one end of the aquarium, turn the flashlight on then off, then immediately put food in the aquarium where the light appeared.

    3. Repeat step 2.

    4. Turn the light on and off without supplying a food reward.

    5. Note the location of the fish in the tank.

    6. Make sure there are no additional external stimuli, such as sound changes in the area of the tank or movement around the tank. Keep the location of the light and food consistent.

    7. Repeat steps 2–5. Record observations and draw conclusions.

Teacher's Guide
Kings of Camouflage
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