What happens when animals in the wild see their reflections in a mirror for the first time?
The experiment was conducted by an innovative French photographer, Xavier Hubert Brierre.
He and his wife travelled to Gabon, in Africa, and set up a mirror and motion sensors in several locations to capture the animals' responses as they walked by, Mail Online reported.
A video, showing the animals reactions which ranged from indifference to aggression, was posted on YouTube.
The video shows different animals having different reactions. A leopard is seen trying to paw at its own reflection, while an elephant seems to be indifferent and calmly walks on.
But a silverback gorilla reacted with aggression, staring at the mirror for a while before charging at it and trying to attack.
According to Mail Online, only a few animals such as humans are able to recognise their own reflection and most animals respond aggressively, but some primates can display human-like recognition.
This is seen in the video when a group of chimpanzees seem intrigued by the mirror, using it to preen themselves and forming a line in front of it.