A group of chimpanzees in Gabon, Ecuador, got the shock of their lives as they saw their reflections for the first time.
The animals waved their arms and pounded the glass and floor in a bid to intimidate their reflections.
The experiment was carried out by wildlife experts Anne-Marie and Xavier Hubert-Brierre, who were studying animal behavior.
Xavier said: “Some of the chimps quietly observe their reflection, but the younger, more immature animals start to scream and shout.
“They see an opponent in the mirror and try to impress their rival with big bold dance moves.
“But they get more and more angry when they see the ‘other’ chimp copying the moves, and will try even harder to out-do them.”