First, it was "the dress". Is it black and blue or gold and white?
Now, it's "the animal". A scientist named Dan Quintana posted a video of someone petting a black birdbunny with the caption: "Rabbits love getting stroked on their nose."
Since the internet loves a good challenge, people instantly weighed in on whether the mystery creature was a raven or a black rabbit. For the record, Quintana has stated he believes the footage is of a bird. But the optical illusion is still worth checking out!
What say you: BIRB or BUN BUN?