Scientists Find That Bats Communicate With ‘Death Metal Growls’
Some bats use "death metal growls" to communicate by engaging their false vocal chord in a way similar to human death metal singers.
That's pretty crazy, right? Who knew that bats fly around and practice their death metal vocal growls on each other to communicate. Totally brutal!
In the paper, the researchers conclude that a species of bat called Daubenton's bats "extend their lower vocal range by recruiting their ventricular folds — as in death metal growls — that vibrate at distinctly lower frequencies of 1 to 5 kHz for producing agonistic social calls."
The study continues, "The different selection pressures for echolocation and social communication facilitated the evolution of separate laryngeal structures that together vastly expanded the vocal range in bats."
Indeed, it's similar to how humans' own ventricular folds (also known as vestibular folds) "play a role in several low-frequency forms of singing, such as death metal grunting and Tuvan throat singing," the paper says.
How did they find this out? "By filming the bat larynx in vitro with ultra-high-speed video up to 250,000 fps and using deep learning networks to extract vocal membrane motion, we provide the first direct observations that vocal membranes exhibit flow-induced self-sustained vibrations to produce echolocation calls in Daubenton's bats," the study explains. (Below, see a video of the bat vocal folds in action.)
The full, peer-reviewed research paper, titled Bats Expand Their Vocal Range by Recruiting Different Laryngeal Structures for Echolocation and Social Communication, is available to Read at PLOS Biology. It was written by the scientists Jonas Hakansson, Cathrine Mikkelsen, Lasse Jakobsen and Coen P. H. Elemans.
How bat that?