Elephants are already known to be among the smartest creatures on Earth, but the results of a new study have even surprised researchers. After playing recordings of human voices for elephants at Amboseli National Park in Kenya, the animals showed a knowledge of human languages not yet seen in any other non-human species: an ability to distinguish between different languages, reports Phy.org.

Researchers played recordings of voices from Maasai speakers, a group that herds cattle and frequently shows hostility toward elephants, and from Kamba speakers, a language often spoken by employees of the national park, who rarely pose any threat to the mammoth creatures. All of the voices were saying the same thing in their respective languages: "Look, look over there, a group of elephants is coming."

Whenever the elephants heard the Maasai voices, especially when the voices were of adult men (the individuals most likely to threaten elephants), the animals tended to act defensively, gather together and move away. But when the Kamba voices were played, the elephants showed no concern at all, continuing about their business.

"The ability to distinguish between Maasai and Kamba men delivering the same phrase in their own language suggests that elephants can discriminate between different languages," said co-author Graeme Shannon, a visiting fellow at the University of Sussex.

Of course, this doesn't mean that the elephants could understand the meaning of the human utterances. But it does show that they can pick out subtle sound differences in spoken words to identify different groups of people. While many other species are capable of identifying humans by their voices, this is the first time an animal has been found that can tell the differences between human languages.

"It is very sophisticated what the elephants are doing," said Keith Lindsay, a conservation biologist and member of the Amboseli Elephant Research Project. "A lot of animals will take flight at just the general threat posed by people, but a smart animal doesn't do that."

The study comes at the heels of other recent research suggesting that elephants have a specific alarm call for "human," providing further evidence that African elephants are increasingly seeing humans as threats. Taken together, these two studies suggest that the relationship between people and elephants has reached a troubling point, and that conservation efforts to protect these highly intelligent creatures are more important than ever.

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