A group of inquisitive young Celebes crested macaques are fascinated by their reflection in the camera lens. They are pictured in Tangkoko National Park on the Indonesian island of Sulawesi, where the Critically Endangered macaques have become used to humans. Every time a photographer approaches they gather round, captivated, to stare at themselves in the glass. Now, it is a fact that 18-month-old human children take a while before they recognise themselves in a mirror. So it’s possible that some notion of self-recognition is beginning to dawn in the minds of these youngsters.