Seeing with Ears

Materials Needed

· 5 copies of ‘Amazing Echolocation’- download is below

· 5 sleeping masks or other items to be used as blindfolds

· 5 slinkies (optional- you can skip this part)

· A Lab Sheet for each student- download below

Background

Most animals utilize light to see, just like humans do. But some animals have learned to live, hunt, and reproduce in darkness. Unique physical structures on bats support their unique way of “seeing” or sensing the world around them. The statement “blind as a bat” is inaccurate. Bats eyes can see just fine. But their eyes don’t help them when hunting and living in the dark. In order to see perfectly in darkness, they have developed an ability to map their world with sound.

The word echolocation means using “echo” to “locate”. An animal produces a sound and uses the echo of that sound to sense their surroundings. Bats can tell the size, location, and movement of an object through capturing the echoes of their high pitched squeaks or chirps. (The sounds are so high pitched that humans can’t hear them).

Physical adaptations on a bat’s body support echolocation. Special muscles in a bat’s throat allow them to make high pitched squeaks or chirps up to 190 times per second! Extra-large ears with folds allow bats to hear their squeak return echo and translate this into an abundance of information.

Other animals, such as dolphins and toothed whales use echolocation to navigate and hunt in deep dark waters. They have developed special nasal passages and skulls that allow them to “see” incredibly well.

Humans have created ultrasound technology that uses echolocation. We commonly use ultrasound/ echolocation technology in medicine (remember those first glimpses of fetuses in the womb), in deep-sea fishing, and submarines.

A few amazing humans who are blind have learned to navigate their world using echolocation too!

Directions

· Start by asking your students what it would feel like to be blind. How would they get around? Navigate their world? Ask them to think about which senses they would rely upon if they could not use sight.

· Ask students how our senses integrate other information from our environment. Emphasize how the sense (hearing, smell, touch) picks up information, which our brain interprets.

· Tell students that today, we will be learning about bats! Bats have special physical adaptations that allow them to thrive in darkness.

· Place students into 5 groups. Give each group a copy of Amazing Echolocation. Have students take turns reading it.

· Ask students about what they learned. What was new or interesting?

· Tell students you will now show them a video with a lot of the same information as in the reading, you want them to look for new information they learn to share with the class after the short video. Watch the first video on the Video Tab above.

· Ask students what else they learned? Reinforce the concept that bats and dolphins bodies/ physical features have changed to support this new way of “seeing”.

· Optional: Have students go back into their 5 groups. Give each group a slinky and allow them to mimic a sound wave echoing off something. Make sure each student in the group gets a chance to demonstrate the motion of the sound wave.

· Distribute the Lab Sheets to each student. Have them fill them out individually, or in their small groups.

· Collect the Lab Sheets and other materials and tell students they will now get a chance to become bats and insects, to try out echolocation themselves.

· Tell students you will be going outside and you want them to form two groups. You can have the students count off to know which group they are in. You will be playing two games to test their echolocation skills.

Game 1

· Once outside have students in each group hold hands to form 2 circles. Explain that initially, we will have only 1 bat and 1 insect. Everyone will remain still, except our one insect will repeat our bat's chirps.

· Select 1 student to go inside each circle. Have that student be the bat– they should put on the blindfold. Select a student by tapping their shoulder to be the insect. This is the only student that will chirp in response to the bat.

· Have the bat chirp, and the insect respond. Tell the bat to turn slowly in circles until they locate their insect. They should point at the insect before taking off the blindfold. Did they point to the correct student?

· You may switch out students to play this game as many times as you like before playing game 2.

Game 2

· Explain to students that this time you will add motion into the echolocation game. The bat will be able to take 2 steps towards the insects he/or she is hunting, while the insects can take 1 step away from the bat.

· You can choose to play this game as a group, or continue in separate circles.

· You can start with one or two bats, and gradually allow more bats to join the hunt.

· When beginning the game, make sure students are not too far from the bats, so the bats have a chance of catching them.

· Remind students they will be disqualified if they take too many steps. Only one step can be taken by each insect after each chirp from each bat, and only 2 steps can be taken by each bat after each echo chirp from the insects.

· Tell students before you start playing the game that you need them to chirp loudly in response to each bat chirp. You expect everyone to wait in between chirps. It will play out like this,

Þ Arrange students so they are not too far away from the bats.

Þ Bats get blindfolded

Þ Bat/s chirp loudly

Þ All students who are insects chirp loudly in response.

Þ Bats take 2 steps towards insects, while insects can take 1 step away from bats

Þ Repeat until some insects are eaten (bats touch a student)

Þ Repeat game as often as you like to give students an opportunity to play a bat.

Þ Try adding in more bats as you go.

Kids can explore Carlsbad Carverns and learn more about bats in this 360 degree interactive from Google Arts and Culture.

https://artsandculture.withgoogle.com/en-us/national-parks-service/carls...