The last common ancestor with humans and gibbons lived around 20 mya.

Great Apes LCA candidate: Proconsul, an inhabitant of the Miocene forests in East Africa, stands as a landmark in the evolutionary journey toward self-awareness.

This early ape lacked a tail and exhibited a mixture of arboreal and terrestrial traits, providing clues to the social and environmental challenges that likely spurred cognitive advancements. While direct evidence of self-awareness in Proconsul is beyond our reach, its position in the ape lineage suggests the development of social structures and cognitive abilities that predate the sophisticated self-awareness observed in modern great apes, elephants, and dolphins.

Proconsul’s world was one of increasing cognitive complexity, setting the stage for the emergence of true self-aware beings, capable of recognizing themselves as distinct entities within their social and natural environments.