ECHOLOCATION LAB By Donald Mills TYPE OF ACTIVITY : Hands on activity Simulation Group/ cooperative learning Inquiry lab

TARGET AUDIENCE : Most applicable to Biology and could apply as well to Life Science, Special Education and Marine Biology. This lab will help students understand how other animals use their senses and answer an environmental issue.

BACKGROUND INFORMATION :

This lab is a fun lab for both the students and the teacher if its set up properly. First you will need to have a six inch triangle, square and circle cut from stiff plastic, metal and wood. These targets each need to be attached to the top of a ring stand. Secondly you will need a one foot square piece of fish netting attached between two ring stands. For the lab to work well you also need a Super Soaker 100 (two will make the lab go faster). Since this lab uses water you will want to have paper towels on hand and possibly a mop.

Setting up this lab is fairly easy. The most important part is to make sure that where the targets are to be placed has nothing behind it that could make noise, therefore an open window works the best (screen in or out doesn't matter). If you have a tilt in window or no window at all like myself, you can still do this lab with a table set in the center of your room that has an enormous pile of paper towels behind it to soak up the water. From your target area you need to place marks on the floor at one meter, two meters and three meters.

The procedure for this lab is pretty basic. Students working in pairs, one blindfolded and one using the Super Soaker, shoot at the targets and listen to the sound of the water hitting the target to guess the target's shape and the material it is made from.

Preparation time needed: 15 to 30 minutes

Class time needed: 40 to 60 minutes for a class of twenty five.

LESSON/ACTIVITY:

In this lab you will experience how dolphins and other echolocating animals use their senses to locate and identify objects with out using their sense of sight.

Echolocation by dolphins occurs when the dolphin produces sound waves from an area of their head above their eyes called the melon. These sound waves travel forward through the water until they strike something and echo back to the dolphin. The dolphin listens to these echoes and can tell the distance to, shape of, and material the objects made of. Our modern sonar is based on these abilities.

For this lab you will be using a blindfold to remove your sense of sight and a stream of water will replace the sound waves. You will see how distance affects echolocation.

MATERIALS:

Blindfold Super Soaker 100 Plastic triangle target Plastic circle target Plastic square target Metal triangle target Metal circle target

Metal square target Wooden triangle target Wooden circle target Wooden square target Fish net target Paper towels

PROCEDURE :

1. Choose a partner and receive a group number from the teacher.

2. Gather around the lab set up.

3. Choose one person to wear the blindfold while the other uses the Super Soaker.

4. Put the blindfold on and get the Super Soaker ready.

5. Have the teacher place one of the targets on the window sill.

6. From the three meter mark the person using the Super Soaker will shoot at the target going back and forth across the target from just past the target to just past the target, starting at the top and moving slowly towards the bottom. Do not go back up or start over the target again. Go very slowly to make sure you hit each part of the target.

7. The person blindfolded will listen to the sounds and guess the material the target was made of and its shape.

8. Record the data in a chart as shown below.
   Trial number:
   Distance:
   Target material:
   Target shape:
   Material guessed:
   Shape guessed:

9. Switch jobs with your partner

10. After the person is blindfolded have the teacher switch targets or place nothing there at all.

11. Repeat steps six through eight.

12. Record all data from other groups.

13. Repeat steps three through twelve at two meters.

14. Repeat steps three through twelve at one meter.

EVALUATION :

1. Graph the percent shape correctly guessed versus distance.
2. Graph the percent material correctly guessed versus distance.
3. What are the affects of distance on echolocation?
4. Can dolphins echolocate on Tuna nets?
5. What could be done to Tuna nets to make them dolphin safe?

EXTENSION/REINFORCEMENT :

Fellows Collection Index

Activities Exchange Index