Bats have a wider vocal range than Mariah Carey, at an astonishing seven octaves
By Maddy Shaw Roberts
The particular species of bat shares a technique used by only two types of human vocalist – death metal, and Tuvan throat singers.
Few human singers can boast a vocal range of more than a few octaves – Luciano Pavarotti boasted an operatic range of two and a half thunderous octaves, while Mariah Carey’s famous contralto-to-whistle-tone range has been known to touch notes that dolphins would envy.
But according to a new study, the unique vocal stylings of bats trump them all.
A new study on Daubenton’s bats found that the creatures were able to produce a range of frequencies that far exceeds most other vertebrates, including humans.
And for some sounds, bats use the same vocal structures as only two groups of human singers – death metal artists, and throat-singing members of the Tuva people in Siberia and Mongolia.
Researchers are not able to fully understand the meaning of all the creatures’ sounds and songs, but this study allowed them for the first time to see what happens in a bat’s larynx, or voice box, when it produces sound.
Professor Elemans, who led the team of researchers from the University of Southern Denmark, said: “We identified for the first time what physical structures within the larynx oscillate to make their different vocalisations.
“For example, bats can make low-frequency calls, using their so-called ‘false vocal folds’ – like human death metal singers do.”
Bats engage structures in their larynx called ventricular folds, or ‘false vocal folds’, which are found on top of the true vocal cords, to communicate with each other at low frequencies. Only death metal and some throat singers, it transpires, use their false vocal folds like bats.
The study of the bat species, which are found across Europe and Asia, found their average vocal range spans an astonishing seven octaves. “That is remarkable. Most mammals have a range of three to four, and humans about three,” Professor Elemans added.
“Some human singers can reach a range of four to five, but they are only very few. Well-known examples are Mariah Carey, Axl Rose and Prince. It turns out that bats surpass this range by using different structures in their larynx.”
Researchers have long known that vocal communication is important for bats, but the meaning behind some of their noises is still unknown. When flying into or out of a densely packed roost, they will produce growling and grunting sounds.
“Some seem aggressive, some may be an expression of annoyance, and some may have a very different function. We don’t know yet,” said biologist and study co-author Lasse Jakobsen.
Bats also emit short, high-frequency calls when hunting their prey, to help navigate their dark surroundings. They do this by vibrating very thin vocal membranes, which humans once had too.
The findings were published in the PLOS Biology journal on Tuesday 29 November.