In 2016, researchers released a study with an incredible headline: “Monkey vocal-tracts are speech-ready.” The study verified that monkeys are physically capable of human speech but lack the brain capacity to do so. If that’s the case, what’s the deal with birds?

First, get the phrase “bird brain” out of your head. Parrots are actually pretty smart animals. In the wild, they’ve been known to create unique songs so their mates will recognize them. Researchers have found that flocks of parrots have “conversations,” and analysis of their brains shows that they learn languages in a similar way to humans.

Brains aside, birds are unsurprisingly well-equipped for song. They have a totally different voice box than humans, which gives them much more control over their vocal tract. The syrinx is responsible for birds’ incredible range, the ability to produce two sounds at once, and why they can sing continuously.

Some birds use this unique physiology to mimic. Recordings of mockingbirds have shown them imitating various other species including frogs and crickets. Lyrebirds have often astonished researchers with their incredible ability to mimic chainsaws, cameras, and other unnatural sounds. Once you hear that, the ability to mimic human speech seems like the least impressive thing a bird can do.

Check out the video above to get some insight behind the physiology that lets these birds replicate sounds so well, and why they might be doing it.

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