Nature gets the lowdown on the anatomical secret behind the koala’s deep, deep voice:
Benjamin Charlton, a biologist at the University of Sussex in Brighton, UK, wanted to know what gave these marsupial Barry Whites their rumbling bass voice. “The first time I heard a koala bellow, I was genuinely amazed that an animal this small could produce such a sound,” he says.
In 2011, he was part of a team that discovered that koalas have a descended larynx (which holds the vocal cords) — something found only in humans and certain species of deer. This makes their vocal tract longer than expected and helps to produce unusually resonant calls1. But the koala’s laryngeal vocal cords are too small to produce the extremely low fundamental frequencies of the mating bellows, so Charlton and his colleagues, together with Roland Frey at the Leibniz Institute for Zoo and Wildlife Research in Berlin, dissected ten male koalas (Phascolarctos cinereus) to take a closer look.
Focusing on the koala’s throat and soft palate, they found a set of much larger folds that had never been described before, spanning an opening between the nasal and oral cavities of the pharynx — the upper part of the throat behind the mouth and nose but above the larynx.
Benjamin Charlton, a biologist at the University of Sussex in Brighton, UK, wanted to know what gave these marsupial Barry Whites their rumbling bass voice. “The first time I heard a koala bellow, I was genuinely amazed that an animal this small could produce such a sound,” he says.
In 2011, he was part of a team that discovered that koalas have a descended larynx (which holds the vocal cords) — something found only in humans and certain species of deer. This makes their vocal tract longer than expected and helps to produce unusually resonant calls1. But the koala’s laryngeal vocal cords are too small to produce the extremely low fundamental frequencies of the mating bellows, so Charlton and his colleagues, together with Roland Frey at the Leibniz Institute for Zoo and Wildlife Research in Berlin, dissected ten male koalas (Phascolarctos cinereus) to take a closer look.
Focusing on the koala’s throat and soft palate, they found a set of much larger folds that had never been described before, spanning an opening between the nasal and oral cavities of the pharynx — the upper part of the throat behind the mouth and nose but above the larynx.
These ‘velar’ vocal folds are the right size to produce the low frequencies of koala bellows, and Charlton and his team were able to reproduce the sounds by using a pump to suck air through the pharynx and larynx of dead koalas — mimicking the bellows that live koalas make when they inhale.
Yes, that’s pretty grisly. But also – a dead koala’s bellow? That’s so… industrial. Mark Pauline would be jealous.