For twenty minutes, traveling at 500mph there is nothing to be seen that even suggests human existence. Endless ripples and waves of sand eventually give way to fractal like river beds which etch out the surface giving it a land like structure – but no straight lines.

In the distance a patch of ground (probably a huge expanse of land) is a different colour. My mind tells me it is green and fills in lush vegetation, trees and shrubs. But getting closer it seems to be just a different colour of sand and desert pavement, just as empty as what I saw before.

None of the rivers seem to carry water. It is as if the finer sand here flows over coarser sand, finding its level, making its way to the ocean of dunes.

I spot a straight line below – certainly a sign of humanity. Is it a road or a pipeline? It seems to straight to be a road, because where I live landscape and history would be tugging a roads course in multiple directions. Down there, I suppose, if you want to get from point A to point B you go straight. There is no C or D to distract you on your journey. Deviating from the fastest route would mean lingering in the dry sunshine.

The electronic map on the screen in the seat ahead tells me that if I stare out far to the west I might catch a glimpse of Timbuktu, but the sky seems to hazy to let me see, or perhaps it is over the edge of the earth.

The sun reflects from a pool of water – there is something else out there other than sand and rock and sun. In the distance a few more glints. Perhaps I will start to see settlements now. These water sources are like islands in the sea – life is possible. It can be sustained there. But as we fly over the glints disappear. Perhaps these oases are just damp patches, the water quickly draining away, or evaporating. Or maybe just a shinier kind of sand.

Where the world is wildest the signs of human life are orderly – a straight line across a desert. As the world becomes more friendly to us, the marks we make become more haphazard – a village is more confused than a hamlet, a city more chaotic than a town. Complexity is difficult, but simplicity is not necessarily the sign of an easy life.

As we reach the edge of the Sahara, trees begin to appear, dotted and grouped, looking like poppy seeds scattered on the surface of a bagel.

Getting off the plane in Ouagadougou, first I was hit by the warmth – not heat – followed by the smell of burning charcoal…