An Asian elephant is able to imitate human speech. In Korea, 22-year-old male elephant Koshik has learned to speak Korean words, in a bizarre way by keeping his trunk in his mouth.

The news has come just days after a study suggested that a white male Beluga whale in California aquarium learned to mimic the human voice.

Koshik's vocabulary consists of five Korean words - "annyong" (hello), "anja" (sit down), "aniya" (no), "nuo" (lie down), and "choah" (good).

Although earlier reports have suggested that elephants mimic human voice, they have not been further investigated. In the case of Koshik, researchers played his sounds to people who could understand the Korean language. 

They did not find any difficulty in understanding the words. All of them agreed on the overall meaning and the spellings of the words imitated by Koshik.

Researchers also studied the structure of Koshik's sounds using a computer analysis. They found that Koshik imitates human speech by matching his pitch and timbre with that of the human trainers' voices. While they noticed similarities between Koshik's and the human voice, they also found differences from normal elephant calls.

"Human speech basically has two important aspects, pitch and timbre," Angela Stoeger of the University of Vienna, Austria, said in a statement.

"Intriguingly, the elephant Koshik is capable of matching both pitch and timbre patterns: he accurately imitates human formants as well as the voice pitch of his trainers. This is remarkable considering the huge size, the long vocal tract, and other anatomical differences between an elephant and a human," she said.

However, there is no evidence showing that Koshik understands the meaning of the words that he utters. It is also not clear as to what caused the elephant to adopt this bizarre behavior of mimicking human voices. Researchers suggest that loneliness may have forced Koshik to learn the language.

When Koshik was a juvenile about five years ago, he was the only elephant living at the Everland Zoo in South Korea. He might have developed this behavior to strengthen social bonds with humans.

Experts hope the study will help shed light on the evolution and biology of complex vocal learning, which plays a significant role in human speech and music.

The findings of the study are published in the journal Cell Biology.

To take a look at Koshik speaking Korean language with help of his trunk, click here.