"At home" is a perch high above the sea on a rocky ledge along the South African coast east of Cape Town. "Just here" is an indentation on that cliff, a cave some 35 meters above sea level and 100 meters from the coast.

Called Blombos Cave, it's a time capsule sealed tens of thousands of years ago. The cave lies near Cape Agulhas, where the Atlantic and the Indian Oceans flow into one another. The past and present—and perhaps the future—merge here as well.

The cave's opening, an almond-shaped eye, faces the sea. Once, it was shuttered by windblown sand from nearby dunes. But 20 years ago, archaeologist Christopher Henshilwood of the University of Witwatersrand, South Africa, and the University of Bergen in Norway removed Blombos' eye-patch.

What Henshilwood found would change our understanding of human history—and the likely date when our species began to use symbols to communicate information

Dybas, C.L. 2013. Ripple marks—The story behind the story. Oceanography 26(3):10–13, https://doi.org/10.5670/oceanog.2013.69.

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