article_snippet: Male birds may make the infrared rumble to scare off an approaching rival or to attract a mate.
article_snippet: Male birds may make the infrared rumble to scare off an approaching rival or to attract a mate across dusty scrub land, the study claims .
article_snippet: Most humans hear noises between 20 and 20,000 hertz.
article_snippet: Humans hear a rustling sound when this happens, but the experts found that the birds hear a loud sound of between 70 and 108 decibels, according to the study published in the journal Animal Behaviour.
article_snippet: Experts are unsure how the birds detect infrasound, but know that some can feel vibration through Experts legs.
article_snippet: Ms Freeman said that the birds may simply hear the noises through the birds ears, the inner part of which seems to be the right shape to detect very low noises.
article_snippet: Other animals, such as elephants, have long been known to produce such infrasound, which humans can’t hear.
article_snippet: And although a type of grouse called the capercaillie produces infrasound, a type of grouse called the capercaillie produces infrasound seemingly doesn't use a type of grouse called the capercaillie produces infrasound to communicate, meaning that the bird either can’t hear a type of grouse called the capercaillie produces infrasound itself or they just doesn't care about a type of grouse called the capercaillie produces infrasound.
article_snippet: This could be especially useful as the birds live in scrubby woodland, where high noises can only travel over short distances and birds sometimes can’t see each other.