As the expression goes: If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck. Complicating the old adage, a male musk duck named Ripper could talk like a human—or at least, he learned how to mimic a few choice words. The duck, born and raised in captivity at an Australian nature reserve in the late 1980s, was recorded uttering the phrase: “You bloody fool!”
Now, a new study published this week in the journal Philosophical Transactions of the Royal Society B analyzed two sets of old recordings of the bird, reports Ellen Phiddian of Cosmos. The new analysis adds musk ducks to a small number of animals able to imitate human speech.
In 1987, researchers used a Sony Walkman to record Ripper making several peculiar noises, including mimicking the sound of the door to the nature center's aviary with uncanny accuracy and making mumbling noises that resemble indistinct human speech.
However, the most captivating sounds taped are those of Ripper appearing to imitate a sentence he may have often heard from one of his keepers: "You bloody fool!" The second set of recordings were taken of another unnamed male musk duck in 2003 and capture the bird making the same door-slamming sounds, as well as imitating the cries of a Pacific black duck it was raised in captivity with.
The researchers behind the study also report two other examples of musk duck mimicry, though recordings of these talented quackers don’t exist, reports Donna Lu of the Guardian. One duck at a United Kingdom nature park seemed to imitate the snorts of a pony, while another bird made sounds much like the coughing of its keeper and the squeaks of a turnstile.
Musk ducks now join in an exclusive group of non-human animals, including some songbirds, parrots, hummingbirds, whales, seals, dolphins and bats, that can learn to mimic such a variety of sounds, reports Christa Lesté-Lasserre of New Scientist.
“Vocal learning is a rare and special trait, so that makes this duck particularly special,” lead author Carel ten Cate, an animal behaviorist at Leiden University in the Netherlands, tells New Scientist.
While most animals are born innately knowing to make certain sounds, those with the vocal learning trait can acquire the ability to produce new sounds that they're exposed to frequently. This skill could be important to musk ducks because the courtship process among males involves specific high-pitched vocalizations, reports Jennifer Hassan of the Washington Post.
In the case of Ripper and the other musk ducks covered in this study, the fact that they were hatched and hand-raised by humans as opposed to other musk ducks could have led them to start imitating people and other noises instead of adults within their own species, reports Jackson Ryan of CNET.
This study also sheds new light on how the vocal learning trait evolved among birds, reports Tibi Puiu of ZME Science. The taxonomic order Anseriformes, which includes ducks and other waterfowl, is hypothesized to have split off from other mimicking birds at least 90 million years ago. This means vocal learning either evolved independently in musk ducks or arose in a common ancestor longer ago than previously thought.