gibbon
Gibbons are able to speak to one another in sentences with grammatical rules. Romain/Flickr

Gibbons appear to speak to one another in a language similar to that once used by human ancestors, researchers have discovered.

In a study of white-handed gibbons in Racine Zoo, Wisconsin, researchers have identified a series of calls that serve as a method of communication for the animals.

According to a report in New Scientist, zoologist Angela Dassow and computer scientist Michael Coen have developed algorithms that recognise this ape speak.

Dassow and Coen believe many animals communicate in far more advanced ways than we realise and are looking at a number of creatures, including gibbons and dolphins, to provide evidence supporting their theory.

They believe animals have sounds that they can build into sentences with rudimentary grammatical rules – and that they can create a translator so we can decipher what they are saying and talk back.

Gibbon conversations have been recognised since 2006 when researchers thought their songs might provide specific information. Coen heard about the work and wanted to get involved in learning more about their language.

Dassow was initially brought in for her talent of being able to howl like a wolf: "She was so sensitive to the wolves' vocalisations that she could identify them individually based on sound. When I heard that, I wanted her on board," Coen said. The zoologist then sat with the gibbons for hours on end to try to make sense of their songs.

Eventually, they were able to create an algorithm that made sense of the sounds: "In spectrograms all the [gibbon howls] look the same," Coen says. "With the algorithm they are all wildly distinct. You would never confuse them."

The researchers found 25 different 'words', including warnings about specific predators, such as leopards and snakes. The gibbons are so specific, they also have a word to tell if the predator is stationary.

Findings also showed females used more words than males: "A male may be saying 'We're being attacked,' but the females are the alphas, so maybe they're the ones giving instruction on what to do. [For example, she might say] 'leopard, climb higher," Coen said.

Explaining the possibility of a machine that would let humans talk back to gibbons, Coen said this is in the pipeline. He has programmed a keyboard to play different components, but has not yet tested it over concerns that they might learn to ignore the sounds.

Speaking previously to the Journal Times, he said: "The bottom line would tentatively seem to be that language is far more universal than linguists believe."