Echolocation in Bats

Subject
ITEAR
Topic

Topic: Echolocation in Bats

Purpose: To understand how bats use echolocation to meet their need of finding food.

Prior Knowledge: Students may have some base knowledge of bats.

Materials

Playground ball

Butcher paper or dry erase board

Nighttime (owls hooting) /daytime sounds (forest sounds with birds chirping)—iPod and speakers

Blindfold  

 
Hook/Engage

Role on the Wall (Modified)

Draw a shape of a bat on the chalk/white board. Ask students what they have learned about bats so far. If they need more help, ask: What needs do bats have? What do they eat? How do they sleep? Where do they live? What time of day are bats awake? Bats are awake at nighttime and sleep during the day, this means they are a nocturnal animal. Write the responses inside the bat shape.
 
Transition: "Friends, you know so much about bats! Do you think we could be bats using our bodies, voices and imaginations?"
 
Explore

Narrative Pantomime

1. Outline playing area: "The cave is our home (tape off an area of the floor). The rest of the floor is the forest. We have to stay in these areas to be safe bats. Let’s close our eyes and listen to the forest sounds." (Play day and night sounds)  Decide which sound is day and which sound is night. "What do you hear? How do you know whether it’s a day or night sound?" Discuss the sounds—birds are awake during the day and crickets are awake at night, so that’s how we can guess . "We are going to use these sounds to know when we can leave our cave and when to come home. Everyone stretch out your wings and flap them—make sure they work!"
2. Bat Cave: "Now friends, let’s fly to our bat cave. The lights are on and we can hear our daytime sounds. So let’s go to sleep like bats. Let’s make sure we all have our own space in the cave. How do bats sleep? If we are very careful, can we try to sleep upside down with our feet in the air?" (Judge the space you have to work with and the personality of the students—this may be too much ) "Make sure you don’t kick another bat." 
3. Nighttime Flying: "Now, when you hear nighttime sounds and the sun goes away, you can wake up and start flying around the forest." Play nighttime sounds for them and turn off lights (if the room is safe and still well lit). "Fly around the room, start slowly, then a little faster, then quiet bats sneaking up on insects. Give them a moment to explore flying."
4. Eating Insects: "All that flying makes bats very hungry. Everyone find an insect for dinner. And eat it! Keep flying. Can you find another insect to eat?" Find one more insect. 
5. Bat Bedtime: "Now my bats are getting sleepy. They’ve eaten lots of insects and it’s starting to get light outside. When the sun comes up, they have to go back to their cave and go to bed." (Turn lights on, turn daytime sounds on.)
 
Transition: "Alright when I turn off our forest sounds, we are going to become humans again. (Fade out music) Can we sit around the edge of the carpet in 5-4-3-2-1. Good work being bats, friends!"
 
  • What did you do as bats?
  • How did you find insects? What senses did you use? 
  • How do you think bats can see insects at night?
 
Define Echoes and Echolocation
 
Bats have a very special way of finding insects at night. It’s called echolocation. Write the word on the board. Sound it out together. Say the word together. Break it down together—What does echo mean? What does location mean? Define words as a group. Bats use their mouths and noses to make a sound that is so high that we can’t even hear it! Then, they wait to see if that sound echoes back to them.
 
Transition: "Let’s see if we can use our voices and bodies to try to make an echo in our classroom!"
 
Human Echo
Have students stand up and make a line, shoulder to shoulder facing the teacher. "Friends, you are now my wall and I am going to say some words/sounds and they are going to bounce off of you and echo back to me. So, I will say something and you will echo it back. Let’s try it." The teacher can have fun with this—use the word echo or echolocation or make silly sounds, etc. If there is time, invite some students to stand in front of the wall and make a sound/say a word .
 
Ball Echo
"Now, we are going to make an echo, using a ball. This ball is going to be my voice. I am going to throw my voice into the wall. What do you think is going to happen if I throw this ball (my voice) at the wall? Let’s try it. What happened—were we right? What if I roll the ball out the door? What do you think will happen? Try it. What happened? Why didn’t the ball stop? This is how bats know if there is a bug in front of them. They send out a sound using their nose or mouth and if it comes back to them, they know there is a bug in front of them. And that’s how they catch their dinner." On the board, draw a picture of a bat sending an echo out to a bug and receiving the echo back. "So, just like you used your hearing to find bugs when we were pretending to be bats, real bats have to use their hearing to see at night." If they understand this concept, extend it to: "What if the echo takes a long time to get back to them? What do you think that means?" Try it, using the ball. "What if it takes a short time to get back to them? Try it again. So, a bat knows how far away the bug is by how quickly their echo comes back to them."
 
Transition: "Now, we are going to pretend to be bats and insects and play a game to try out echolocation. Let’s make a circle."
 
Insect Echolocation Activity
1. Break the students up into 4 groups in the circle formation. There should be windows between the doors (groups). Tape out spaces for students to stand inside of . 
2. All of the students are going to be insects. Give them a moment to figure out how insects move and sound. "Move/Sound like insect for 5-4-3-2-1! Freeze, insects." Practice moving like insects without sound. "We’re going to have to be very quiet insects to not get eaten by the bat!"
3. Now, model the game with the teacher standing in the middle of the circle. The person in the middle wears a blindfold and the teacher will turn her around a few times to ‘disorient her.’ 
4. The person in the middle is going to try to find the insects by echolocation. She will make a beep sound and point her finger where she thinks there are insects. If the insects echo back her beep, she can eat them for dinner! She flies over to them and the insects say ‘EEK!’ and melt to the ground. If there are no insects where she points there will be silence and she has to try again. 
5. Side-coach the insects to be as quiet as possible or the bat will know where they are before she uses her echolocation. 
6. Between each bat, encourage the insects wiggle and make their insect sounds. Make sure everyone gets a turn.
 
Transition: "Good job, friends! Let’s take a seat in our circle."
 
Reflection

Describe: What did we do today?

Analyze: What sense does a bat use to find insects? What is the special way they use their hearing?

Relate: What if the echo comes back to the bat quickly? What if it comes back to the bat slowly? Do we know any other animals that use echolocation?

Lesson written by Meg Greene