At Laetoli, Tanzania, a layer of rain-dampened volcanic ash preserved a trail of footprints left by hominins about 3.66 million years ago. Over roughly 27 meters you can make out an arch and a big toe in line with the others, just like ours. A simple stroll that became the oldest direct evidence of upright walking.
Around 2300 BCE, Enheduanna, daughter of King Sargon of Akkad, became high priestess of the Moon god at Ur. She composed hymns to the goddess Inanna and put her name to them. She is the oldest person identified as the author of a literary work, about 1,500 years before Homer.
Squeeze Earth's 4.5 billion years into a single 24-hour day. Homo sapiens shows up around 11:59:54 p.m., roughly six seconds before midnight. All of written history, from Sumerian tablets to today, fits into the final tenth of a second. A cosmic blink.