Organic materials decay MUCH faster than Synthetic ones and both are made of natually occuring substances. The only advantage organic material has is its ability to self-repair. Which is exactly what we do when we replace the cables. Repair them.
Geological activity could theoretically naturally form a latticework of connected copper and gold veins of a similar structure to what the trees created in Avatar.
Don't get me wrong here. I don't think in the real-world it is even concevably possible that such a structure exists. But WERE a Gaia to exist and be sapient I think that those sorts of structures are the most likely form that its neural pathways would take.
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