Animal disguises.

Background

Many animals, whether they are the hunters (predators) or the hunted (prey)--or both, use disguise to hide from other animals. Carnivorous (meat-eating) animals disguise themselves to sneak up on their prey. A polar bear blends in with the snow to attack a seal. An orchid mantis hides among real flowers, waiting to pounce on a fruit fly. Both large and small animals hide in order to avoid becoming lunch.

Types of Disguise

The word camouflage can be confusing, because it is sometimes used to mean any type of disguise that helps an animal hide and, is sometimes used to mean specifically, colors or patterns that help an animal blend into the background. From white arctic animals to brown desert-dwellers, many animals have fur or feathers the same color as their habitats. This is called concealing coloration. Another type of disguise is disruptive coloration. Animals using disruptive coloration use spots, stripes, or other patterns to disguise themselves. The pattern makes it hard for a predator to see an animal's shape. A leopard's dark spots help him blend in with shadows in the grass. A zebra's stripes help him to hide in the grasslands at dawn and dusk, when lions hunt. Also, when zebras stand in a group, their stripes blend together, making it difficult for a lion to pick out the shape of one zebra to attack. Under water, many fish use not only crazy patterns but also frills and crests to help disguise their shape. When a predator looks, he sees bits and pieces but can't manage to make out an entire fish shape.

Some animals disguise themselves in the truest sense of the word--as sticks, rocks, flowers, leaves, or other objects--even bird droppings. When disguised as an inanimate (nonliving) object, animals must either stay perfectly still or move in a believable way (such as a bright green chameleon walking slowly and swaying to look like a fluttering leaf). Stick insects tend to feed and mate at night, because moving during the day would ruin their disguises.

Chameleons are famous for changing color, yet chameleons change color to communicate and not to disguise themselves. However, other animals do use color change as a method of disguise. The cuttlefish can change color as it swims to match the patterns of the ocean floor. The leaf-tail gecko can gradually change its skin to match the color and pattern of the lichen patches on a tree trunk as it waits for an insect. In addition to animals that can quickly change color (octopus is another), some animals change color seasonally. The snowshoe hare and the ptarmigan (a bird) are brown in the summer and white in the winter.

Another type of disguise is mimicry. A harmless animal may try to mimic the appearance of a more dangerous animal in order to scare away predators. Moths disguise themselves as hornets or spiders. Nonpoisonous snakes mimic the coloration of deadly snakes. Caterpillars have spots that look like snake eyes.

Opening Activity:

The day before beginning the Animal Disguises unit, ask students to color a paper fish so that it can be hidden/camouflaged somewhere in the classroom. Then have each student tape his or her fish to its hiding spot. The fish must be in plain sight (not under a desk). The next day, ask students to count how many fish they can see from their desks. Discuss which fish are easiest to see and which are hardest to see and why.

Another option: have students look through Where's Waldo? books. Have them try to find Waldo. Discuss why Waldo is hard to find (there are many people wearing similar colors and patterns).

Level Pre-A

Main Concept: Animals hide from other animals. Animals use colors to hide by blending in with their homes.

Initiating Questions (Levels Pre-A and A):

1. Why do animals need to hide?

2. How do animals hide?

3. Why is the color of an animal important for hiding?

Follow-up Questions:

1. Why do animals try to look like sticks or leaves?

2. How can stripes or spots help an animal hide?

3. What is another way animals use disguises to hide?

Picture Activity

Ask students to look at all the animals. What do they have in common? All of the animals are white, Why are they all white? They have fur color that matches their homes. Why? It helps the animals hide, Do you know why the animals want to hide?

Vocabulary

Say each of the words out loud. Have the class spell each word out loud together as they write. Point out the picture of the rabbit hiding in the grass. Ask students to think about other ways animals can hide.

Weekly Lab

Decide in advance whether to have students cut out the polar bear shapes or to provide them with pre-cut shapes. The cut-lines are light to lessen contrast. For pre-cut shapes, they may be photocopied beforehand (one bear up to 200% scale). Trim away the cut-lines to increase the effect. Hold up one example so students can see from a distance. Point out that if the polar bear lived in a forest, it would stand out the way the polar bear cutout stands out on the brown paper. Tell students that polar bears are really big--they can weigh about 1,000 pounds! They need to hide so they can sneak up on seals.

Another option: instead of using brown paper, have students draw a forest on a white piece of paper and then glue the second polar bear onto their forest.

Math

Answer: 5 animals: deer, moose, brown bear, rabbit, squirrel 

Storytelling 

Ask students if any have ever seen an insect like the one in the picture. Did it surprise them? Did they feel afraid or curious? How did they find out that it was alive? Encourage students to use their imaginations. Stories can be realistic or fanciful.

Challenge

Answer: There are two cheetahs. They are the same.

Bringing It Home

After students complete the puzzle at home, talk to them about how each animal blends in with its habitat and how the colors of the animals help them hide.

Level A

Main Concept: Animals hide from other animals. They use colors to help them hide by blending in with their homes. Some animals pretend to be sticks or leaves to help them hide.

Picture Activity

See Level Pre-A.

Vocabulary

After completing the VOCABULARY, discuss the meanings of the words.

Writing in Science

FLY-pothesis could poke the stick and see if it moves. He could offer it leaves and see if it eats.

Weekly Lab

(See Level Pre-A.)

Ask students what would happen if polar bears were brown (they would stand out in the snow). Ask students what would happen if polar bears lived in forests instead of in the snow (they would stand out the way the white polar bear cutout stands out on the brown paper).

Challenge

Answers:

1) D; 2) A; 3) B; 4) C

Discuss with students how the colors of the animals match their habitats to help them hide.

Math

Answer: 3 + 3 = 6

Bringing it Home

This is a fun and creative project that is intended to reinforce the concept of animal disguises and provide interaction with family members about the topic being studied. The activity should also provide the chance for students to show how well they understand. Have students bring their projects back to school to compare with the other students.

Level B

Main Concept: Animals use disguises to hide from other animals. Animals use colors that help them blend in with their habitats. Some animals have disguises that make them look like sticks, leaves, or flowers.

Initiating Questions (Levels B and C):

1. Why do animals need to hide from other animals?

2. Why is the color of an animal important for hiding from other animals?

3. What are other ways an animal can hide?

Follow-Up Questions:

1. Why are disguises important for animals?

2. How can stripes or spots help an animal hide?

3. Do you think it is more important for fast or slow animals to use disguises? Why? Which type of disguise would you want to use if you were an animal? Would you want to disguise yourself by using colors and patterns to blend in with your habitat? Or, would you want to disguise yourself by looking like a stick or a flower? Why?

Vocabulary

Answers: 1) B; 2) D; 3) A; 4) C

Weekly Lab

After completing the LAB, suggest to students that the Apple Jacks[R] represent two species of insects--one that is camouflaged (the green Apple Jacks[R]) and one that is not (the red). The students represent birds that are hunting for insects to eat. Ask them which species of insect they would want to be--the green or the red. Help them understand that the green "insects" are less likely to get caught and eaten. Ask them, "What if the grass were red?" (The red insects would be harder to catch.) What if the grass were brown or covered with white snow? (The two species would be equally easy to catch.)

Math

This is a simple math problem where students use subtraction to find the difference. However, the math problem is the logical follow-up to the WEEKLY LAB, where students take the resulting data and make calculations in an attempt to answer their original question--in this case, How does camouflage work? The final answer should clearly show that the Apple Jacks[R] (the green ones) that were harder to see in the grass avoided "being found" or caught by other animals. Talk to students about how this demonstrates what happens to insects in nature.

Writing in Science

This is a good opportunity to talk about the different parts of a letter. Primarily, this exercise will encourage students to really think about different types of camouflage, and why some kinds may work better than others.

Challenge

Answers:

A--2) a stick insect (walking stick);

B--4) a grass lizard; C--3) a decorator crab;

D--1) a flower mantis

Bringing it Home

See Level A.

Level C

Main Concept: Animals use disguises to hide from other animals. Animals use colors and patterns that help them blend in with their habitats. Some animals have disguises that make them look like sticks, leaves, or flowers. Many different kinds of animals use disguises.

Vocabulary

Answers: 1) disguises; 2) habitat; 3) camouflage; OCTOPUS

Weekly Lab

(See level B for initial discussion topics.)

If students are grasping the concepts easily, take it one step further: ask them what will happen to the red insects over time. The answer is that gradually, the red insects may die out. In each generation, many insects will get eaten, some of them before they have a chance to reproduce. Therefore, the population of red insects will keep shrinking. Meanwhile, the green insects will take over.

Math

Draw a chart on the board; where students will record their WEEKLY LAB data. The chart should have one column labeled RED APPLE JACKS FOUND and one column labeled GREEN APPLE JACKS FOUND. The chart should have the same number of rows as there are students in the class. This way, each student can record his or her data in one row.

Writing in Science

Discuss with students different types of camouflage used in the ocean. Brightly colored fish may stand out in the open sea but will blend in to the coral reef.

Some fish try to blend in with the ocean floor. Others, like the cuttlefish, look like rocks. Sea dragons look like sea horses except they appear to have leaves attached to their body, making them blend in with weeds. Many fish have patterns of stripes or spots or frills so that it is harder to see the outlines of their bodies (in other words, predators can't spot a "fish" shape).

Challenge:

Answers:

A--4) a stick insect (walking stick);

B--6) a grass lizard;

C--5) a decorator crab;

D--1) an orchid mantis;

E--2) a copperhead snake;

F--3) a katydid 

Puzzle

Answer:

It is harder to find the words in the right-hand puzzle because they are camouflaged--they are surrounded by similar words ("animil," etc.). The words in the left-hand puzzle are not camouflaged, so they stand out, the way a brown bear would stand out in a snowy habitat.

Level D

Main Concept: Animals use disguises to hide. Certain animals hide from their predators; other animals hide to sneak up on their prey. Some animals have disguises that make them look like sticks, leaves, or flowers. Other animals blend in with their habitats, using either concealing coloration or disruptive coloration.

Initiating Questions (Levels D and E):

1. Why do animals need to hide from other animals?

2. Which kinds of animals need to hide?

3. What are some ways that animals can hide from other animals?

Follow-up Questions:

1. What are some types of animal disguises? Which do you think works best? Why?

2. Why do you think some animals try to stand out instead of trying to blend in with their habitats?

3. What time of day do you think stick insects usually eat? Why?

Vocabulary

Answer:

1) concealing coloration;

2) disruptive coloration;

3) disruptive coloration;

4) concealing coloration

Weekly Lab

Make sure students read over the WRITING IN SCIENCE activity first. During this activity, discuss with students the different types of camouflage used by fish living in the coral reefs. Brightly colored fish may be the same colors as the coral reefs (also, bright colors may often appear darker underwater). Stripes can also help the fish hide in the coral, and spots confuse predators by looking like extra eyes.

Math

First, have students draw a simple chart they can use to organize the data collected during the LAB activity. Discuss with students what a percent means (the number out of 100--in this case, how many fish out of every 100 fish would have been caught). Discuss why the number of students is multiplied by 30-because each group of two students made 30 blue fish (which would be only 15 per student), but then the 30 blue fish were used twice for 60 fish total per two students or 30 fish per student. Explain that percentages are one major way scientists communicate their findings to others.

Writing in Science

This activity extends and enhances the WEEKLY LAB activity. Discuss with students the importance of having a clear hypothesis and being able to state it logically in a complete sentence. The LAB follow-up is important too--being able to keep accurate records of results and recording the data for comparison in a format that make sense and is easy for others to see.

Puzzle

See Level C.

One possible sentence could be: "A polar bear is easily camouflaged in the snow but not in a forest."

Meet the Scientist

Tell students that Dr. Huffard decided to be a marine biologist in middle school. However, when Dr. Huffard was in high school, the career counselors discouraged her from studying marine biology. They said she wouldn't be able to get a job or make enough money. Dr. Huffard followed her love of studying sea creatures anyway. Now that she is a marine biologist, she loves it! She has to work hard but she enjoys it. In addition to studying octopuses, Dr. Huffard enjoys traveling to the places where the octopuses live. She gets to see new places, meet new people, and try new foods. She has even learned the Indonesian language!

Level E

Main Concept: See Level D.

Vocabulary

See Level D.

To extend this activity you may offer incentives or rewards to students who have the most complete, extensive or well-documented research.

Weekly Lab

See Level D.

Math

Discuss bar graphs in general with students and explain why they are a useful tool for scientists who need to communicate their data to others. Show how bar graphs are much easier to read than raw text data.

Writing in Science

See Level D.

Puzzle

Answer:

1. The bird eggs are camouflaged. They are colored to match their surroundings. The eggs shown in the picture are plover eggs. (After baby birds are born, they are usually dull in color, too. Later, when they can protect themselves, they develop the brighter colors we associate with birds.)

2. The seal sees the polar bear's big black nose!

3. Some animals and birds--including the snowshoe hare--change color with the seasons. They are brown in the summer and white in the winter.

Meet the Scientist

See Level D.

DID YOU KNOW??

Some moths, either as babies or adults, disguise themselves as bird poop.

DID YOU KNOW??

There are many species of walking stick insects. Some look like bare twigs, others look like sticks with dried leaves attached, and a few even look like broken sticks.

DID YOU KNOW??

Baby chameleons are the color of tree bark. When the babies are big enough to look like leaves, they turn the bright green color of adult chameleons.

DID YOU KNOW??

Rather than trying to blend in, some animals use bright colors to try to stand out. These animals, such as bright red and orange frogs, are often poisonous--their colors serve as a warning to predators.

A stick walks. A flower attacks. A leaf, fluttering in the breeze, suddenly eats a worm. What??? You guessed it. The stick, flower, and leaf are all animals in disguise. The stick is actually an insect called a walking stick. The flower is actually an orchid mantis (or-chid man-tis), which waits, with wings that look like petals, until it sees a tasty fruit fly. The leaf is a bright green chameleon (cha-me-leon). He walks slowly so as to look like a fluttering leaf.

Which Animals Use Disguises?

Many different animals use disguises--big animals, little animals, fast animals, and slow animals. Some animals, like moths and deer, may use disguises to hide from predators (pred-a-tors) who want to eat them for lunch. Other animals, like polar bears and leopards, use disguises to sneak up on their food, or prey.

What Kinds of Disguises Do Animals Use?

Some animals try to look like harmless objects. A moving octopus might look like a rolling coconut or a clump of weeds. A cuttlefish might look like a rock. Other animals try to look more dangerous than they are. This is called mimicry (mim-ic-ry). A nonpoisonous snake might have the same pattern as a deadly snake. A moth might look like a stinging hornet. Animals use mimicry to scare away predators.

Blending In

Other animals blend in with their surroundings. Some animals have fur or feathers the same color as their background. This is called concealing coloration (con-ceal-ing col-or-a-tion). A white polar bear hiding in the snow and a grey spider hiding on a rock are both using concealing coloration. Another type of disguise is disruptive coloration (dis-rup-tive col-or-a-tion). Animals using disruptive coloration have spots, stripes, or other patterns to disguise themselves. Patterns make it hard to see an animal's shape. A leopard's dark spots help him blend in with shadows and grass. Zebras use disruptive coloration too. Their stripes help them blend into the grasslands at dawn and dusk, when lions hunt. The stripes also make all the zebras blend together, so a lion can't pick out one zebra to attack.

DID YOU KNOW??

Some moths, either as babies or adults, disguise themselves as bird poop.

DID YOU KNOW??

Polar bears can weigh about 1,000 pounds. Without camouflage, they would never be able to sneak up on their prey.

Vocabulary

Underneath each picture, write either "concealing coloration" or "disruptive coloration."

HOW many other animals can you think of that use each type of coloration? Do some research on the Internet or in library books. Make a list of animals, indicating which type of camouflage each uses. Did you discover any other types of camouflage? Compare your list with your classmates.

Weekly Lab

Which type of camouflage works best?--Is disruptive coloration or concealing coloration more effective? Before beginning this LAB, read over the WRITING IN SCIENCE section on the following page. Remember to write down your prediction first.

You need: white paper, blue paper, newspaper, tape or glue, scissors, watch

Step 1: With a partner, cut out 30 small fish (all the same size) from white paper and 30 fish from newspaper.

Step 2: Make three "oceans." Tape or glue four white pieces of paper together to make a white ocean. Tape or glue four blue pieces of paper together to make a blue ocean. Then cut a piece of newspaper to be the same size as the other two oceans.

Step 3: One partner should close his or her eyes while the other partner carefully places 30 white fish in the blue ocean. When the fish are all ready, the partner who arranged the fish will say "Go!," time 10 seconds using the clock, then say "Stop!"

Step 4: When the other partner hears the word "Go!" he or she will open his eyes and pick up as many fish from the white ocean as possible before hearing "Stop!" Record the number of fish collected.

Step 5: Repeat steps 3 and 4 switching jobs.

Step 6: Repeat steps 3-5 except put the white fish in the white ocean.

Step 7: Repeat steps 3-5 except put the newspaper fish in the newspaper ocean.

Math

Analyze the results of your WEEKLY LAB

1. Add up the total number of white fish caught from the white ocean by you and your partner.

2. Add up the total number of white fish caught from the blue ocean by you and your partner.

3. Add up the total number of newspaper fish caught from the newspaper ocean by you and your partner.

4. Make a bar graph showing your results. Your graph should look something like the sample graph to the right:

[GRAPHIC OMITTED]

Writing in Science

State your hypothesis. Record your results. Analyze your data. Explain your conclusions.

1. BEFORE you begin your weekly lab, write out your hypothesis on a separate piece of paper. Which type of fish do you predict will be easiest to catch--white fish in the white "ocean," white fish in the blue "ocean," or black and white (newspaper) fish in the black and white "ocean?" Which fish will be the hardest to catch? Also, write one or two sentences explaining why you believe your predictions are correct.

2. AFTER you finish your lab and graph your results, check whether your hypothesis was correct.

3. White fish in the blue ocean have no camouflage. White fish in the white ocean use concealing coloration. Newspaper fish in the newspaper ocean use disruptive coloration. Which type of camouflage worked best--concealing coloration or disruptive coloration? Write a few sentences describing the results of your lab and explaining why you think one type of camouflage worked better than the other.

DID YOU KNOW??

Some butterflies have large spots on their wings that look like eyes. These fake eyes confuse hungry birds, so the butterflies can escape.

DID YOU KNOW?? Some fish are dark on the tops of their bodies and light on the bottoms. If predators look down on these fish, the fish blend in with the dark ocean floor. If predators look up at the sunlit ocean surface.

Puzzle

Discuss these animal disguise brainteasers with a partner.

1. How does a baby bird use camouflage before it is even born?

2. When a polar bear is hunting for seals in a snowstorm, what is the first clue a seal has that the polar bear is coming?

3. How can an animal blend in with its surroundings in the summer, when everything is green and brown, AND in the winter, when everything is white with snow?

DID YOU KNOW??

Some lizards gulp air to make themselves look bigger and scare away predators.

Meet the Scientist

Crissy Huffard, Marine Biologist, University of California, Berkeley 

Dr. Crissy Huffard (at right) sometimes spends 11 hours in one day underwater studying octopuses. She uses a video camera to record their behavior. She also has special paper made out of plastic so she can take notes underwater. Dr. Huffard studies octopuses in Indonesia.

Octopuses do not have hard shells like clams and snails (which are related to octopuses). This means they don't have much protection from other animals. So disguise is very important for octopuses. They try to match the colors of the algae and seagrass where they live. The octopuses also have muscles to make their skin look bumpy, which helps them blend in.

Dr. Huffard liked studying water animals even when she was in elementary school. She enjoyed catching fish, snails, and crabs. In college, she had the chance to study octopuses for the first time, in Hawaii. Ever since, she has loved working with octopuses.

Weekly Resources

Helpful Sources for Planning Your Science Weekly Classroom Activities

Recommended Resources

* Clarkson, Jan Nagel. Tricks Animals Play. Washington DC: National Geographic Society, 1975.

* Lovett, Sarah. Animal Disguises (Extremely Weird). NY: Avalon Travel Publishing, 1997.

* Martin, James. Hiding Out: Camouflage in the Wild. NY: Crown Publishers, Inc., 1993.

* Tides, Phyllis Limbacher. Animals in Camouflage. MA: Charlesbridge Publishing, 2000.

Internet Resources

http://www.smithsonianmag.si.edu/smithsonian/issuesO5/octO5/wolfe.html

http://www.pbs.org/wgbh/nova/leopards/seeingsans.html

http://www.thaibugs.com/mantises1.htm

http://www.npr.org/templates/story/story.php?storyld=4561136