The evolution of abstract thinking and symbolic behaviour

When our ancestors discovered over 2.6 million year ago that splitting a stone made it into a better tool, they began the long voyage that led to modern humanbehaviour. This timeline shows the oldest evidence found for some of the major milestones that marked this evolution, from the earliest stone tools to the firstwriting systems.

Please note: As dating technologies advance and new artifacts are found, our understanding of our ancestors' lives and capabilities continues to evolve. This timelinereflects our scientific knowledge as of 2015.

Dates are approximate. Numbers below the timeline represent thousands of years before the present.