Chimpanzees, one of our closest living relatives, possess remarkable cognitive abilities. One intriguing aspect of their behaviour is their interaction with mirrors, which can provide insights into their self-awareness and cognitive capacities. This study aims to investigate how captive chimpanzees utilise mirrors, specifically focusing on their ability to alter mirror orientation to locate hidden food items.

I present the chimps with two flat platforms. On one of them, there is a transparent triangular barrier at the front, on the other one an opaque barrier, under which grapes can be hidden from view of the chimpanzees. Behind these barriers, a mirror has been installed which lies flat, but which has a paper strip attached to it to allow the chimpanzees to flip the mirror up and manipulate its position. When the mirror is flipped up, in theory the chimpanzees can use it to find where the grape has been hidden.

Will they choose to flip the mirror up to spot the food hidden behind the opaque barrier? In which one of the two situation (transparent or opaque) will they be faster and more accurate at retrieving the food reward? Let’s find out!