[ad_1]
Humans and animals have different hearing ranges, with humans able to hear between 20 and 20,000 Hz. Audiograms and audiometry tests are used to measure hearing. Dogs have a wider range of hearing than humans, while mice can communicate via sounds inaudible to humans. Dolphins communicate differently than other marine mammals.
Hearing range refers to the different frequencies that can be heard by humans or animals. The frequency that can be heard varies throughout our lives, and a test known as an audiogram is used to measure the sounds a person can hear. There is a significant difference between the hearing range of humans and mammals which explains why humans cannot hear noises made by some animals.
The hearing range of humans is between 20 and 20,000 Hertz (Hz). By the time humans reach their adolescence, this upper range is significantly lower, and most oral communication occurs between 200 and 8,000 Hz. Frequencies of 1,000-3,500 Hz are the most sensitive to the human ear. Ultrasound refers to sounds above the hearing range, while sound below the range is known as infrasound.
An audiometer is used to test the hearing of humans. This apparatus allows the subject to hear various frequencies on special headphones. A minimum hearing curve is used to compare test results. This curve represents the normal hearing range.
An alternative method of finding out a person’s hearing range is a behavioral hearing test known as audiometry. This test involves a range of tones at a certain pitch and intensity. Subject raises hand to indicate hearing sound. The tester then records the lowest intensity sound that can be heard by the subject.
Dogs have a wider range of hearing than humans. They can hear sounds between 40 and 60,000 Hz. Depending on the breed, dogs’ ears have a minimum of 18 muscles that allow them to tilt and rotate their ears to amplify sound. Sounds that seem loud to a human scare dogs which respond well to ultrasonic signals in training whistles. Domestic breeds make ideal watchdogs as their listening range allows them to hear intruders clearly.
The hearing range of mice is between 1,000 and 90,000 Hz. While they are unable to hear the same low frequencies as people, they can communicate via sounds inaudible to a human. This is also useful when under attack. Mice are capable of sending warning sounds to other rodents without a predator hearing them.
Bottlenose dolphins have a hearing range of between 250 and 150,000 Hz. However, dolphins communicate differently than other marine mammals such as whales. While whales use low-frequency pings and moans, dolphins use higher-frequency clicks and whistles.
