Drylands are like skin cracking from dehydration. When rainfall decreases, plants don't vanish overnight: they rearrange, leaving bare patches of soil between them. These patterns are visible even from space.
Scientists compared satellite images of eight arid regions, from the Sahel in Africa to Australian deserts. It turns out that the history of a landscape is written in the shape of its vegetation patches. If the climate became drier, plants gathered into regular hexagonal patterns, like honeycombs. If moisture increased, patches merged into disorderly clusters, resembling scattered inkblots.
This method works like an ecosystem health detector. A single satellite image is enough to tell whether a region is heading toward desertification or recovering. No drilling rigs, no field expeditions, just a view from above.
Vegetation patterns are like tree rings, but for an entire ecosystem. They tell the story of past climate and warn about the future.
In the most arid places, plants can be spaced tens of meters apart, yet still form perfectly regular hexagons that are only visible from high above.