Before we get into any of this, a quick note on scale.

When historians talk about ancient civilizations, they tend to reach for words like

remarkable or enduring or storied. When paleoanthropologists talk about the afar region of

Ethiopia, they tend to go quiet for a moment and stare at something in the middle distance.

There is a difference in magnitude that language has a hard time bridging.

We are not talking about a few thousand years of interesting events. We're talking about

millions of years of biological and geological history converging in a single landscape,

producing conditions that are, as far as the evidence shows, unique on this planet. So if

what follows occasionally sounds like an attempt

to describe something that exceeds the normal vocabulary of historical narrative, that is because it

does. To understand Ethiopia, you have to go back, not a few centuries, not a few millennia,

but all the way back to a moment so distant that the concept of history hadn't even been invented yet,

mostly because the creatures walking around at the time hadn't gotten around to inventing anything at all,

including language, tools, and the general notion that tomorrow might be different from today.

We're talking about the deep past, the kind of past that makes ancient Rome look like something

that happened last Tuesday. And here is the thing that makes Ethiopia genuinely unlike anywhere

else on earth. You don't have to take anyone's word for it. The evidence is right there in the

ground, stacked up like chapters of the longest book ever written, waiting for someone with

enough patience and a very sturdy brush

to read it. Somewhere in the northeastern corner of Ethiopia, where the land opens up into a vast

sun-baked basin called the Afar triangle. The soil holds a record of life that stretches back

further than most people can comfortably imagine. This is not a metaphor. The bones

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