Death metal singers have a vocal counterpart ... in bats

It's not just a love of the dark that bats and death metal singers share.

Bats have a wide vocal range, from high-pitched clicks to lower grunts. A new study in the journal PLOS Biology found that for some of the lower frequencies, they seem to use the same technique singers use for death metal growling or Tuvan throat singing.

How can bats make different noises? They make low-frequency calls and echolocation calls at the same time. Coen Elemans is the lead researcher on the study. The best singers have a vocal range of five or six. All bats can do seven.

Ultra high-speed video, filming up to a quarter million frames per second, was used to study bats' vocal tracts.

According to Elemans, bats make echolocation calls using thin membranes that extend from the vocal folds. We were able to get those to vibrate easily, but they were vibrating at very low frequencies.

Humans have false vocal folds because they have no function in normal speech. There is some evidence that these folds are recruited in extreme singing.

The false vocal folds are lowered a little bit towards the vocal folds and they make a lot of lower frequencies. Their vibrates become irregular. The quality of death metal singing is given by that.

The bats couldn't be asked what it was like to make sounds at low frequencies, so we asked some humans.

It goes from your stomach to your chest to your legs. It is a full-body thing for me to do.

The lead singer of the death metal band Obituary spoke from the back of his tour bus. Tardy says the death metal growl can be a problem.

We play most nights if not six nights a week. It can be a large amount. I sleep like a baby at the end of the night.

Chase Mason is the lead singer of Gatecreeper.

I think that when my vocal cords are getting shredded or beaten up, it makes it sound better. I think that I'm doing a good job if there's a small amount of blood in my throat.

Mason wouldn't have looked at the similarities between the sounds bats make and the ones he makes.

He thinks it's cool that people compare you to animals like a bear or growling animal. It's very dark and frightening. Vampires and other dark things are associated with the imagery of a bat. It's definitely correct.

John Tardy felt the same way.

Bats are great.

It was edited by Mallory Yu.

Christopher Intagliata edits the audio story.