2. Speed of Light – Speed of Sound
• You can see a flash of Lightning almost instantly
• But it takes a while before you hear the thunder
• You can count to tell how far away it is
• Sound takes about 5 seconds to go 1 mile

3. Sound Waves

4. What can they hear?
• Humans – up to 20,000 Hz
• Dogs – up to 40,000 Hz
• Cats – up to 60,000 Hz
• Bats – up to 100,000 Hz
• Dolphins – up to 150,000 Hz

5. What do sound waves look like?
Human
Thunder = low frequency

6. What are echoes?

7. What is Echolocation ?
"Echolocation is the use of sound waves
and echoes to determine where objects
are in space”
In other words, echoes help to find the
location of an object.
http://askabiologist.asu.edu/echolocation

8. How is Echolocation used by
animals ?

9. • Bats send out sound waves using their mouth or nose.
• When the sound hits an object, an echo comes back.
• The bat can identify an object by the sound of the echo.
http://askabiologist.asu.edu/sites/default/files/echolocation.jpg

11. Blind as a Bat?
• Most bats regularly eat flying insects.
• Bats can see as well as humans, but
echolocation is much more important to
them than their eyesight for finding food.
• Bat’s Echolocation is so precise that it can
detect an object the width of a human hair.
• Mother bats who are feeding their babies,
may catch and eat up to 4500 insects in one
night!

12. They can even tell the size, shape and texture
of a tiny insect from its echo .

13. Some moths have developed ways to get away or confuse
bats, such as:
• Furry wings that don't reflect bat echolocation
pulses.
• Sensitive membranes that can 'hear' echolocation
pulses. When the pulses are detected, the moths fly
in crazy patterns or fold their wings and dive to
confuse their hunters.
http://academic.reed.edu/biology/professors/srenn/pages/teaching/web_2007/pf_site/adaptation.html

14. Bats using Ultrasound to Catch Prey
Click on photo to start video

15. Books you might enjoy!

16. The Tiger Moth

17. The Tiger Moth Can can emit ultrasonic clicks
to "jam" a Bat's sonar!
This moth produces ultrasound not to
communicate, but as a way to protect itself. By
producing ultrasound of its own, it is able to
ward off bats by acting as a radar jammer,
confusing the bats so that the moth cannot be
located. By doing this, they add another
weapon to their survival mechanisms that also
includes poison. http://en.wikipedia.org/wiki/Arctiidae

18. Philippine Tarsier
The tiny Tarsier, only 4 inches long, can communicate
using ultrasound. The Tarsier is the only primate
known to communicate in this way.

20. The Dolphin uses nasal passages to make a click and sends
it through its forehead, which focuses the sounds together
into a beam before sending it into the water.

21. • When the sound hits an object in the water, it bounces
back to the dolphin as an echo.
• The dolphin absorbs this returning echo through its jaw.
• A passage of fat from the jaw conducts the sound to the
dolphin's inner ear
• The dolphin can tell things about the object, such as size,
shape and material.

23. The crickets, Arachnoscelis, is from the Katydid family. It
lives in the tropical rain forests, and can produce the
highest-frequency ultrasound of any known insect. These
sounds are emitted by the lonely male, which makes its
presence known with a burst of intense sounds. Listen to
their calls!

24. Arachnoscelis arachnoids, a rare species of katydid from Central
Northeast of Colombia, uses elastic energy and wing movement
to reach volumes greater than 110 decibels, which is louder than
a diesel truck or a subway train.
http://www.sci-news.com/biology/science-bushcricket-colombia-01265.html

25. House mice use Ultrasonic sounds to attract mates.
Rats and other rodents also use it to communicate.

27. The Huia Cavitympanum is the only known frog species
that can communicate using purely ultrasonic calls. This
unusual frog lives in the Philippines. These frogs can hear
sounds up to 38 kilohertz, the highest frequency any
amphibian species has been known to hear.

28. What are some of the
ways animals use
Ultrasound and
Echolocation?

29. As you have seen, many animals use
Echolocation to help them move about in
low light and to locate food. They also use
Ultrasonic sounds to communicate.
From watching animals and through
scientific experiments, humans have
learned to use Echolocation, SONAR and
also RADAR in many different ways.

30. Science Technology Engineering
• Science looks at Nature and explains it
• Technology figures out how to make
Science useful
• Engineering builds new things using
Technology

31. How Is Echolocation used by humans?
Humans cannot create or hear ultrasound, by
themselves, but we can make devices that do this
for us.

32. How it works:
1. A chirp is emitted from the “speaker”
2. It bounces off of an object
3. The echo returns to the microphone
4. The time it takes to travel to the object and back is used to figure out the distance

33. Robots

36. Driverless Cars
http://www.dailymail.co.uk/sciencetech/article-2261574/Audi-A6-Our-man-Las-
Vegas-highway-road-test-car-drives--parks--itself.html

37. http://wbbw1.bwbx.io/cms/2012-04-09/0409_GigaOM_car_630x420.jpg

39. http://www.economist.com/node/21560989

40. The Driverless Car is equipped with
radar sensors monitoring up to 820ft
ahead, a wide-angle video camera that
monitors lane markings. It also has 8
Ultrasonic Sensors. It can even park
itself, squeezing in to within 4in of
another car.
Read more: http://www.dailymail.co.uk/sciencetech/article-2261574/Audi-A6-
Our-man-Las-Vegas-highway-road-test-car-drives--parks--
itself.html#ixzz2xT65l5od

41. http://america.aljazeera.com/watch/shows/techknow/blog/2013/10/24/-techknow-need-toknow6questionsyoushouldaskaboutdriverlesscars.html

42. The Tactic Device for the Blind

43. How the Tactic Works

44. • The Tactic can help the blind move around
safely.
• It is mounted on your wrist and uses ultrasonic
sensors set above the knuckles that can pick up
the distance of objects from one inch to 10 feet
away
• It then translates that distance to pressure on
the wrist--the closer the object, the more
pressure on the wrist.
Read more at: http://phys.org/news/2011-09-tacit-device-safety-video.html#jCp

45. The Hand Bat

46. • The Hand Bat is a simple Do It Yourself (DIY)
device similar to the Tactic
• It uses an Arduino Microcomputer, an
ultrasonic sensor and a beeper
• It is built in a low-cost waterproof flashlight
case
• When you point it in different directions, it
sends out an ultrasonic sound and listens for
the echo
• It figures out the distance and tells the user
how far away an object is with different sounds

47. Human Echolocation
Ben Underwood was a very
special kid. He was blind
since the age of 3 when he
had to have both eyes
removed due to cancer. His
mother helped him to
believe that he could still do
mostly anything he wanted
to do even though he could
not see.
http://www.theguardian.com/lifeandstyle/2007/jan/27/familyandrelationships.family2

48. Ben learned to use clicking
sounds and echolocation in
the same way in which bats
and dolphins use it. Using
this method to avoid
obstacles, he was able to
ride bikes, play basketball
and participate in
many other activities most blind people are never
able to do. Sadly, Ben passed away in 2009 after the
cancer returned.
Learn more: http://www.youtube.com/watch?v=AiBeLoB6CKE

49. The True Story of Ben Underwood