Orangutans are one of our closest relatives. We share 97 percent of the same genetic code in our DNAs as our primate cousins. New research has been done that claims that orangutans have been able to exhibit speech skills never before believed possible.
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.
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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.
Here is video of “Rocky” making controlled vocalizations in order to get treats. The sounds Rocky make were compared to other orangutans in both captivity and the wild, and found to be different enough to show that Rocky was controlling his voice the same way we do.