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Digital - 8.2 Lesson 12 Hearing in Animals
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Teaching Of Science (SEC 395)
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Academic year: 2022/2023
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Hearing in Elephants, Dogs, and Humans
In class, you explored some of the structures found in human ears
that help humans detect and understand sounds. We know, for
example, that humans are able to hear sounds with different
pitches because the human cochlea and the basilar membrane
inside it have different areas that detect different pitches.
The ability of humans to hear a wide range of sounds depends on the structures in the inner
ear. Some of the key structures that affect hearing range are (1) the ratio of the width of the
cochlea at the base (bottom) compared to the apex (top), (2) the stiffness of the basilar
membrane, and (3) the structure and organization of the hair cells.
Both elephants and dogs also have a cochlea, but as you can see in
the chart below, they are able to hear a different range of pitches
of sound than humans. The chart below shows the range of
hearing in hertz (Hz), which is the number of waves per second.
Animal
Lowest frequency sound
they can hear
Highest frequency sound
they can hear
Elephant 17 Hz 10,500 Hz
Human 31 Hz 19,000 Hz
Dog 64 Hz 44,000 Hz
A dog whistle, also known as silent whistle or Galton's whistle, is
a type of whistle that emits sound in a higher range of
frequencies than humans can hear. Some other animals,
including dogs and domestic cats, can hear these higher
frequency sounds so this whistle is used in their training. It was
invented in 1876 by Francis Galton and is mentioned in his book Inquiries into Human Faculty
and Its Development. In the book, he describes experiments to test the range of frequencies
that could be heard by various animals, such as a house cat.
The maximum upper range of human hearing is about 19,000 Hz for children, declining to
around 16,000 Hz for middle-aged adults. The top end of a dog's hearing range is about
44,000 Hz, while a cat's is 64,000 Hz. These data suggest that there are some high-pitch
sounds that children can hear that adults cannot. Most people do not have whistles they can
use at home to test whether or not the people or pets in their families can hear certain
pitches. However, there are computer apps available online that produce sounds of different
frequencies. You must try the Online Tone Generator found at
onlinetonegenerator/ with friends or people in your family. Record your results on
question 2.
Q1: Based on the information in the table above, which of these three animals—an
elephant, a human, or a dog—can hear the lowest pitch sounds?
Q2: Summarize your results from the Online Tone Generator in the space below.
The Humpback Song
Courtesy of Thomas L.
Acoustics is a major area of study for whale researchers. The humpback whales' song is
probably the most complex in the animal kingdom. Researchers study their songs and use
this information in many areas of marine research and technology.
The humpback song, which is made up of repeated themes, can last for up to 30 minutes
and some humpbacks sing for hours at a time! Only the males sing and all male humpbacks
in the same region sing the same song. The song itself changes over time, making it different
Whale Songs Similar to Other Animals
Researchers have noted that whale songs sound very similar to the songs of hoofed animals,
such as. Elk (bugleing), cattle (mooing), and have more than a passing resemblance to some
of the elephant noises. One of the leading researchers into humpback whale sounds, Katy
Payne, also studies elephant sounds and has found similarities between these two species.
Where are Sounds Produced?
The larynx was originally thought to be the site of sound production in cetaceans but
experiments on live, phonating dolphins showed that the larynx does not move during
vocalizations. Instead there are structures in the nasal system including the nasal plug and
the elaborate nasal sac system which move when sound is produced, although the exact site
of the sound generation is still debated. You can read more about this fascinating subject in
book called BIOLOGY OF MARINE MAMMALS, by Reynolds and Rommel.
Try Listening for Yourself
Click on each Box to Hear
Humpback
Song A
Humpback
Song B
Humpback
Song C
Q3: Listen to the humpback songs. Can you tell which parts of the songs are the higher
frequencies (short and high pitched) and which are the lower frequencies? How would you
describe these songs in words? What do the songs remind you of? How are the three songs
similar and how are they different?
Q4: A whale's low frequency sounds can travel up to 10,000 miles. Using the internet,
explore how far this distance is. Imagine you are a whale; how far can you sing? Give an
example of two places that are 10,000 miles apart.
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Digital - 8.2 Lesson 12 Hearing in Animals
Course: Teaching Of Science (SEC 395)
20 Documents
Students shared 20 documents in this course
University: Pennsylvania Western University, California
Was this document helpful?
Hearing in Elephants, Dogs, and Humans
In class, you explored some of the structures found in human ears
that help humans detect and understand sounds. We know, for
example, that humans are able to hear sounds with different
pitches because the human cochlea and the basilar membrane
inside it have different areas that detect different pitches.
The ability of humans to hear a wide range of sounds depends on the structures in the inner
ear. Some of the key structures that affect hearing range are (1) the ratio of the width of the
cochlea at the base (bottom) compared to the apex (top), (2) the stiffness of the basilar
membrane, and (3) the structure and organization of the hair cells.
Both elephants and dogs also have a cochlea, but as you can see in
the chart below, they are able to hear a different range of pitches
of sound than humans. The chart below shows the range of
hearing in hertz (Hz), which is the number of waves per second.
Animal
Lowest frequency sound
they can hear
Highest frequency sound
they can hear
Elephant
17 Hz
10,500 Hz
Human
31 Hz
19,000 Hz
Dog
64 Hz
44,000 Hz
A dog whistle, also known as silent whistle or Galton's whistle, is
a type of whistle that emits sound in a higher range of
frequencies than humans can hear. Some other animals,
including dogs and domestic cats, can hear these higher
frequency sounds so this whistle is used in their training. It was
