Move over, Pavarotti! World's only singing lemur opens its mouth wider on higher notes - just like a trained soprano

The world's only singing lemur uses special techniques shared with the very best opera singers, according to a new study.

Researchers discovered that Indris lemurs open their mouths wider when they try to hit the high notes.

The higher the note, the wider these musical tree-dwellers open their mouths.

Scientists say that this is the first direct evidence that wild indris carefully co-ordinate their mouth movements with the pitch of their song.

By opening their mouths wider, indris change the shape of their vocal tract – the mouth, jaw, and tongue – to match the frequency of the note, amplifying the sound.

What makes this so surprising is that this same technique, known as formant tuning, is something that human opera singers train for years to master.

Co-author Dr Chiara De Gregorio, from the University of Warwick, told the Daily Mail: 'Before microphones were invented, opera singers had to find ways of projecting their voices to the back of large theatres.

'Both opera singers and singing indris appear to use a configuration of the vocal tract that helps maximise the intensity of particular frequencies, making the sound more effective at a distance.'

In their paper, published in the journal PLOS Computational Biology, researchers discovered indris' incredible talents by analysing 83 video recordings of 19 wild indris.

Using motion-tracking tools, the researchers were able to examine the lemurs' singing frame by frame and map their lip movements to the pitch of their song.

This showed that the lemurs were opening up wider in order to hit the higher notes and make the most of the natural amplification of formant tuning.

This is extremely important because singing isn't just a pleasant pastime for the indri lemurs, but rather an essential survival mechanism.

Indris live in small family groups in the dense rainforests of Madagascar and have to defend large territories containing the resources they need to survive.

'Remarkably, much of this territorial defence – around 90 per cent – is achieved through singing rather than physical confrontation,' says Dr De Gregorio.

'Every morning, groups produce these remarkably loud, far-carrying songs to advertise their presence to neighbouring groups and signal that their territory is occupied.'

Using singing techniques to make their calls carry further means that indris can communicate over long distances across their territory without needing to physically patrol the boundaries.

Researchers have found that indri calls are loud enough to travel up to 1.2 miles (two kilometres) through thick forest. 

Dr De Gregorio says: 'What is fascinating is that a relatively simple adjustment of the vocal tract can have such an important ecological function.

'Sound travels much faster and farther than an animal could move through dense forest, so vocal communication provides an extremely efficient way of advertising and defending a territory.'

Likewise, the researchers suggest that these findings could hint at the origins of humans' only musical abilities.

Humans and lemurs both descend from the same primate family, last sharing a common ancestor around 74 million years ago.

This vast gap means that the similarities in singing techniques are likely a product of convergent evolution.

That means it is the same solution reached independently by two different species across deep evolutionary time in order to solve a similar problem.

Dr De Gregorio says: 'Our findings suggest that some of the mechanisms that make human singing effective may not be uniquely human inventions.

'This does not mean that human singing evolved directly from indri singing, of course, but it shows that some of the underlying principles of effective vocal communication can evolve independently in different species facing similar communication challenges.'