In science, we study primates to learn about ourselves. Orangutans share 97% of their genetic code with humans and have common traits like increased brain size, sociability, and handy opposable thumbs.
And now, there’s one more trait that we may share with our great ape cousins: speech.
Researchers at the University of Durham in Britain have successfully used a learning game to get an orangutan at the Indianapolis Zoo to mimic human sounds in a conversational context, something that has never been done before with primates.
This discovery could shed light on how humans first developed the abilities that would lead to speech.
Here’s lead researcher Adriano Lameria in New Scientist, explaining what science stands to gain from this discovery:
“This opens up the potential for us to learn more about the vocal capacities of early hominids that lived before the split between the orangutan and human lineages to see how the vocal system evolved towards full-blown speech in humans.”
Previously researchers believed that orangutans did not have control over their voices, instead only making involuntary sounds of arousal. But this research clearly shows that they have the potential to control their own voices.
To discover this, scientist played a “game” with eight-year-old Rocky where he gets rewarded for copying sounds made by the scientists that included a various range of different tones and pitches.
The sounds Rocky created in these games were compared with the sounds from over 120 orangutans in captive and wild populations, and found to be markedly different when it comes to Rocky’s ability to control his voice in the same way that humans do during a conversation.
Although it doesn’t look like we’ll soon be having intelligent discussions with our orangutan brothers, this level of voice control could clarify the picture of how humans adapted to exhibit the most dynamic language skills in the natural world.