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Acoustics & High Frequency Animal Communications

Animals with small heads and narrow-spaced ears hear high-frequency sounds better than creatures with larger heads and ears that are set widely apart. Small terrestrial mammals typically can hear high-frequency sounds because their small skulls have short ear canals and narrow tympanic membranes. Primates lack those characteristics so it's no surprise that humans have restricted hearing with regard to high frequencies.

Elephant Communication
- Elephants make a range of sounds, which include high-frequency trumpets, roars and cries. The frequency within an elephant's call is considerable. It can start with a rumble of 27 hertz (Hz) and end with a roar of 470 Hz. Elephants can produce very loud sounds that reach frequencies as high as 10,000 Hz and as powerful as 112 decibels. Depending on how the elephant holds its mouth, tongue and trunk, it can both amplify and change various components of the sound. The animal creates specific calls by holding the head in a certain posture and by moving its ears in a certain rhythm. In addition, by lengthening or shortening its vocal chords, an elephant can produce a range of frequencies.
Marine Mammals
- Although the baleen whale species hear better in low frequencies, the toothed whales, such as porpoises, dolphins and beluga whales, hear best at high frequencies. These intelligent sea-going creatures communicate at higher frequencies between 10 kHz and 110 kHz. New technologies allow scientists to measure a whale's hearing in less than an hour. Seals and sea lions, such as elephant and harbor seals have increased sensitivity from low to high frequencies.
Domestic Animals
- Domestic cats and their owners both share the same lower limit of about 20 Hz, but cats can detect frequencies as high as 64,000 Hz, while humans can only hear up to 20,000 Hz. People are most sensitive to sounds of 3,000 Hz, while cats hear best at about 8,000 Hz. Dogs can't hear frequencies quite as high as cats, but can detect frequencies up to 45,000 Hz.
Echolocation
- Both bats and the toothed whales developed high-frequency hearing and echolocation that assist these creatures in finding and capturing prey. These animals can detect the size, shape and density of objects. High-frequency sound waves have a short wavelength that makes it easier for animals such as bats and toothed whales to detect their prey. Their hearing also allows the whale or bat to differentiate between their own call and other background noise, which is at a lower frequency.

Animals & Science