Their analysis of a new set of videos reveals Snowball - who lives at a bird sanctuary in Indiana - not only has rhythm but is also capable of creativity and spontaneity when he boogies.
He utilises various parts of his body to perform as many as 14 different moves - none of which were taught to him by humans or other birds, according to his owner.
The fact that Snowball could perform so many different moves was very surprising, said Aniruddh Patel, a cognitive scientist at Tufts University and a senior author of the study, published on Monday in Current Biology.
"It helps show that this is a more complex cognitive ability than we had even first imagined," he said.
While the internet is littered with videos of animals "dancing" nearly all the examples can be explained away by training.
Bears and monkeys can be taught to dance at circuses, but Patel said such displays do not qualify as true dancing because they are based on operant conditioning.
Such animals learn that if they move in a certain way, they either reap a reward or avoid a punishment.
Snowball's performance is clearly different.
"Snowball developed this behaviour spontaneously," Patel said. "He was never given a food reward for any of this. He was never taught to make dance moves."
Snowball has been dancing since he was dropped off at the Bird Lovers Only Rescue in Indiana in 2007.
(The bird's previous owner, who had grown older and could no longer care for Snowball, even left a copy of a Backstreet Boys album along with the rest of the bird's things.)
But the cockatoo's dance routine was pretty simple when Patel first studied him - mostly just some head bobbing and feet lifting.
But Patel said that after the first experiment, Snowball's new owner, Irena Schulz, told him the bird was starting to add new moves and combinations to his repertoire. In fact, he seemed to be exploring.
So Patel and Schulz, who is also a co-author on both papers, set up a new experiment.
This time, the humans played Queen's Another One Bites the Dust and Cyndi Lauper's Girls Just Wanna Have Fun while filming Snowball. Each song was played three times, with no other input than the occasional attaboy from Schulz.
Later, R. Joanne Jao Keehn, a cognitive neuroscientist at San Diego State University and a classically and contemporarily trained dancer, broke Snowball's movements down frame by frame and categorised them into distinct moves.
When a wavelike movement passed through the bird's head and then body, that was termed a "body roll".
When Snowball lifted one leg and then bobbed his head from left to right, the scientists classified it as a "vogue".
From "headbangs" to "head-foot syncs", the scientists learned that while the bird had many moves that he liked to try, he usually only did each for three to four seconds at a time.
Even still, virtually none of the movements were what anyone would consider natural for a cockatoo.
(Wild cockatoos, of course, also do not have the benefit of having Freddie Mercury as a wingman.)
"Certainly, they do movements as part of courtship," Patel said. "But many of the moves we see in this study are things nobody has ever reported in the wild in terms of cockatoo behaviour."
Snowball is not the only parrot with a hit dance video on the internet. After extensive searching, the scientists found evidence of true dancing in nine other pet parrot species, from green-winged macaws and black-capped lories to black-masked lovebirds and Alexandrine parakeets.
The weird part is no other animals are known to do this - not even other primates, our closest kin.
So why would humans share such a seemingly complex behavior with a bunch of birds?
Patel and his colleagues think it might have something to do with the convergence of five traits, all of which Snowball and his brethren possess.
"There's complex vocal learning. There's the ability to imitate nonvocal movements. There's the tendency to form long-term social bonds, because Snowball seems to do this as a social bonding behaviour," Patel said.
"There's the ability to learn complicated sequences of actions and being attentive to communicative movements."
Patel said dolphins might have those same five traits. But because they live underwater, dolphins' main social bonds are with their own kind, even in captivity. Snowball and the other dancing birds have bonded with humans.
Now that it is clear Snowball is capable of keeping a beat and also honing his style, Patel and his team want to try to understand the bird's motivations. The team is analysing data from another experiment in which they recorded Snowball under three conditions - listening to music by himself; listening to music with Schultz in the room; and listening to music while Schultz dances with him.
"We want to see if this matters in terms of how much he moves and how he moves," Patel said.
"This social context, does it play a role in his behaviour?"
While Snowball and his pop-locking peers may look like a good time, Patel cautions against getting a bird just to watch it cut a rug. For starters, not all parrots can dance, and many are extremely demanding pets.
"They have the personality of a 3- or 4-year-old, and they can live for 50 years," Patel said.
"They end up getting dropped off at bird shelters because people can't deal with the level of attention they need."
