Animal Symmetry: What Symmetry Is This?

All animals, whether simple or complex, show some type of symmetry. The simplest animals, the sponges, have an irregular shape, and scientists describe them as asymmetrical. All other animals have amore definite body design. A sea anemone is considered to have radial symmetry because all its body parts are arranged around a central axis, much like the spokes of a bicycle wheel. Humans and many other advanced animals show bilateral symmetry. If a plane were passed through the midline of the body, the left and right sides would be almost exact mirror images of each other. In this activity you will show your understanding of the three types of symmetry by imagining that each letter of the alphabet is an animal and deciding which type of symmetry each represents.

Materials

Large index card

Pen or pencil

Ruler

Activity

1. Turn the index card so the longest portion of the card is horizontal to you.
2. Use the ruler and pencil to divide the card into three equal columns. Label column 1 as ''Asymmetry,'' column 2 as ''Radial symmetry,'' and column 3 as ''Bilateral symmetry.'' Draw a horizontal line beneath all three of these words.
3. Starting with the letter A and going through letter Z, identify the type of symmetry shown by each letter. Place all twenty-six letters in one of the three columns.

Follow-Up Questions

1. Which letters of the alphabet represented the same symmetry as a sponge?
2. Name three animals that have the same type of symmetry as the letter A.

Answers

1. Answers will vary, but students might list letters such as K, L, or E.
2. Answers will vary, but students should list three animals that have bilateral symmetry, such as humans, apes, or dogs.

Extension

Look at the letter O. What type of symmetry does it have? Name three animals that have the same symmetry as the letter O. Do you think this letter could have more than one type of symmetry?