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Comment by themitigating | Hacker News Reader

"might kill us, but then new creatures will evolve and grow, with plastic being part of their ecosystem, perhaps even desirable."

Is that possible? As far as I know nothing consumes rocks and they've been around forever.

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I've been in a huge magnesite mine, tens of km of underground corridors, with big cathedral like spaces bored in a mountain. The biggest use for all this rocks is feeding meat producing cows with supplement minerals. So, yes, we all eat rocks.

There are already bacteria that eat (some) plastics. Plastics, unlike rocks, are basically just hydrocarbons, not that different from sugars and starches and quite digestible if you have the right enzymes. Whether or not animals could evolve to do it is another story, though.

Unlike rocks, plastic is high in energy (as evidenced by the fact that you can put it on fire).

Sure, but petroleum is also high in energy. There are even some bacteria that consume it. Yet petroleum is still available in huge deposits.

Deposits are the key, it generally isn't readily available on the surface where most of the living organisms are

I think lichens break down rocks. I know there are some microbes that do it.

For something to be consumed it needs to have energy surplus. Plastics have plenty, you could just set fire to them to combine them with oxygen to get it.

They only obstacle is to figure out set of enzymes that can do the burning in controleed manners. Life is very good at figuring that stuff out, it just takes time.

Rocks pretty much don't burn. Although I wouldn't be surprised if in water environments there are some organisms that can utilize some rocks in their metabolism. It's just that rocks are pretty much useless on the surface that's why nothing eats them here.

Similarly with coal underground. In airless environment coal is just rock. If there was plenty of it on the surface something would metabolise it for energy. I think coal from burnt forest doesn't just remain on the ground. Something probably eats it.

> Is that possible? As far as I know nothing consumes rocks and they've been around forever.

Can you burn rocks? No. Can you burn plastics? Generally yes. Therefor there is useful energy to be extracted from plastics.

NB, the quote was " part of their ecosystem" not "consumes". Molluscs, corals and diatoms construct out of rock-like materials, so making minerals part of their ecosystem is a thing.

Already happening. See https://www.science.org/doi/10.1126/science.aad6359

> As far as I know nothing consumes rocks

Rocks do turn into soil which is then the basis for stuff to grow on it.

Through acidic chemicals released by plants they are not consumed

Consumed for minerals, not for consuming high energy chemical bonds.

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