Everyone knows that parrots can mimic human speech. So can a few other birds, including ravens and starlings. But it's not just birds that speak up. Here are a few less obvious examples of animals that have learned to sound like people.

1. Asian Elephant

At least one elephant is using his trunk for more than just eating. Koshik, a 22-year-old Asian Elephant in a Seoul, South Korea zoo, has learned to reproduce five Korean words— "annyeong" (hello), "anja" (sit down), "aniya" (no), "nuwo" (lie down) and "joa" (good)—by placing his trunk inside his mouth to modulate sound. This, says an international team of researchers who have been studying the elephant since 2010, is a “wholly novel method of vocal production.”

Koshik’s trainers first noticed that the pachyderm was imitating them in 2004. The best evidence that Koshik is actually mimicking humans is that the sound frequencies of his words match those of his trainers; researchers believe he learned to mimic human speech because he was lonely (Koshik was separated from other elephants when he was 5). He’s better with vowels than with consonants—his rates of similarity are 67 percent and 21 percent, respectively. There’s no evidence that Koshik understands the words, though he does respond to certain commands.

And Koshik might not be the only talking elephant. In 1983, zoo officials in Kazakhstan reported that one of their elephants could reproduce 20 Russian phrases, but no scientists ever researched the claim.

2. Beluga Whale

In 1984, researchers at the National Marine Mammal Foundation in San Diego, California, noticed something funny: They would hear people talking around their beluga whale "NOC"’s enclosure, even when no one was nearby. For a while, they couldn’t figure it out, until a diver in NOC’s tank thought that someone had told him to get out. It was, in fact, NOC, who was making a sound like the word “out.”

NOC kept up the vocalizations for a few years, allowing Sam Ridgeway of the U.S. Navy Marine Mammal Program in San Diego to record and study the beluga’s vocalizations. "The speechlike sounds were several octaves lower in frequency than the whale's usual sounds," Ridgeway, who co-authored a recently-released study on NOC in Current Biology, told National Geographic. NOC made the sounds by inflating air sacs to a much higher pressure than he did when making normal whale vocalizations.

NOC, who died in 1999, stopped the vocalizations in the late 1980s—probably, researchers theorize, because he reached sexual maturity. But why was a whale mimicking humans such a big deal anyway? Because NOC learned spontaneously, through listening to the humans around him—a phenomenon not previously demonstrated in cetaceans.

3. Harbour Seal

In 1971, George and Alice Swallow picked up an orphaned harbour seal pup in Cundy Harbor, Maine. They raised the seal—named Hoover, because he ate like a vacuum cleaner—first in their bathtub, and then in a pond behind their house. But when he got too big, the Swallows gave Hoover to the New England Aquarium in Boston, Massachusetts. George told aquarium employees that he thought the seal could talk. No one believed him. But in a few years, when Hoover reached sexual maturity, he began to speak more clearly—complete with Boston accent! The seal could say a number of words and phrases, including "hey," “hello there,” “how are ya,” “get outta here,” “get down,” and his own name (you can listen to Hoover talking here). Hoover laughed, too, and when he died in 1985, he got his own obituary in the Boston Globe. Scientists believe that pinnipeds might help us understand what's involved in complex vocal learning.