What are these mysterious structures in the southern Kalahari?

They look like alien incubation pods, but these massive grass-and-mud structures are home to a species called sociable weaver birds. Like bees, these birds live in hives together, collectively building them out of mud, grass, and other materials in their environments. In the southern Kalahari, they use telephone poles as the structural anchors for their nests.

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What are these mysterious structures in the southern Kalahari?

Photographer Dillon Marsh has captured one way that nature reclaims humanity's modern structures and turns them into something alien and beautiful. He writes:

Sociable Weaver Birds assume ownership of the telephone poles that cut across their habitat.Their burgeoning nests are at once inertly statuesque and teeming with life. The twigs and grass collected to build these nests combine to give strangely recognisable personalities to the otherwise inanimate poles.

What are these mysterious structures in the southern Kalahari?

You can see more of Marsh's evocative photographs of these weaver birds' nests, in a series called "Assimilation," on his website.

What are these mysterious structures in the southern Kalahari?

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What are these mysterious structures in the southern Kalahari?