Some birds have a remarkable talent for dancing, two studies published in Current Biology suggest.
Footage revealed that some parrots have a near-perfect sense of rhythm; swaying their bodies, bobbing their heads and tapping their feet in time to a beat.
Previously, it was thought that only humans had the ability to groove.
The researchers believe the findings could help shed light on how our relationship with music and the capacity to dance came about.
One bird, Snowball, a sulphur-crested cockatoo (Cacatua galerita eleanora ), came to the researchers' attention after YouTube footage suggested he might have a certain prowess for dance - especially when listening to Everybody by the Backstreet Boys.
This is a capacity that everyone thought was uniquely human, but we've found evidence that some animals can keep a beatAdena Schachner, Harvard University
Dr Aniruddh Patel, from The Neurosciences Institute in San Diego, said: "We found out that the previous owner usually listened to easy listening music, but he did have this one album, and he noticed Snowball bobbing his head to the Backstreet Boys."
To test Snowball's skill, the scientists filmed him as they played his favourite song at various tempos.
Dr Patel told the BBC: "We analysed these videos frame by frame, and we found he did synchronise - he did slow down and speed up in time with the music.
"It was really surprising that he had this flexibility."
Another group, led by Adena Schachner, from Harvard University, also looked at Snowball, as well as another bird, Alex, an African grey parrot (Psittacus erithacus ).
Dr Schachner said: "We brought some novel music that we knew Alex had never heard before - so there was no way he had been trained to dance to this music.
"We set up the camera and hit play, and we were shocked to see that Alex started dancing to the beat. He started to bob his head up and down."
While Alex's dance routines were not as elaborate as Snowball's, analysis of the footage revealed that he was also able to match his movements with the music he was hearing.
Dr Schachner said: "This is a capacity that everyone thought was uniquely human, but we've found evidence that some animals can keep a beat."
Song and dance
The scientists believe that the parrots' apparent capacity for dance may be linked to another talent that they share with humans - the ability for vocal learning and vocal imitation.
They believe the part of the brain that evolved to allow us and a handful of other species, including dolphins, songbirds, elephants and some cetaceans, to learn and mimic different sounds may also be responsible for the ability to move in time to music.
YouTube footage suggested Asian elephants can dance
To test whether this might be the case, the researchers turned to a vast resource of animal footage - YouTube.
From more than 1,000 videos of different dancing animals, the team found only 33 films that showed animals moving in time to a musical beat.
Dr Patel said: "These 15 species were all vocal learners - 14 parrots and one Asian elephant."
After these initial studies, both teams now want to look more closely at different species' relationship with music.
Dr Patel told BBC News: "No other primates, besides humans, have vocal learning, so there is a strong prediction that no other primates could learn to synchronise to music, even with extensive training.
"However, there are other mammals that have a response to vocal learning - dolphins are a notable category, and I'd love to collaborate with dolphin researchers to find out if dolphins can move to a musical beat."
Dolphins have the ability to mimic sounds - but can they dance?
The scientists believe further research will also provide an insight into how our relationship with music evolved.
Dr Patel said: "Music is a true human universal - it is something we find in every single human culture.
"One of the questions we are asking is whether this is wired into our brains because of evolution, or is it because it builds on other brain systems.
"And this evidence builds on the fact that it is probably linked to other existing brains systems rather than being an adaptation in its own right."
He adds: "You see here a fundamental response to music seen in species that normally don't have a relationship to music in the world.
"They are clearly using a brain system that has a different day job, so to speak."