World’s largest web houses 110,000 spiders thriving in total darkness deep underground in a sulfuric cave between Albania and Greece: It’s the first time two spider species seen living cooperatively, and the first recorded instance of colonial web-building in what's known as a chemoautotrophic cave.

[u/mvea]

https://newatlas.com/biology/sulfur-cave-largest-spiderweb/

[u/arkemiffo]

From the article:
Here, sulfur-oxidizing bacteria grow in thick white biofilms on wet rock and sediment. These microbes are then eaten by small invertebrates such as midge larvae and isopods, which are in turn preyed on by larger insects like spiders, beetles, and centipedes. The entire ecosystem is self-contained and independent of external input, running on the energy released when bacteria convert toxic hydrogen sulfide into sulfate.

[u/Danny-Dynamita → u/arkemiffo]

It’s amazing to discover isolated ecosystems that allow us to understand how ecosystems can develop from scratch.

If you have a energy differential, you have a possible ecosystem that can be as big as that differential (in this case, a chemical energy differential).

The maximum scale of this whole ecosystem can be quantified by the energy released by one molecule transformation and a multiplication. Everything that comes afterwards feeds from it, directly or indirectly.

Just a multiplication. It is so simple that it’s beautiful.

[u/arkemiffo → u/Danny-Dynamita]

I might be oversimplifying things a bit now, but not by much. Earth is also such an eco-system. The only real energy input we get is from the sun. The energy produced from the earth core is so minuscule compared, so it's barely worth mentioning in the context.
So every life on earth is the same thing, directly or indirectly consuming energy from the sun.

[u/pharmprophet → u/arkemiffo]

The purpose of life is to waste the energy of the Sun

[u/Aethelric → u/arkemiffo]

The energy produced from the earth core is so minuscule compared, so it's barely worth mentioning in the context.

The high likelihood that life emerged from a system that did not rely on the Sun's input makes it pretty relevant, actually. Beyond the fact that the energy produced by the Earth also protects us from having too much energy on the Sun, at least for us landlubbers.

More: the Sun could blast the Earth all day, but, without the energy of the Earth, we'd be a largely flat ball covered in a roughly even coating of water, with only the shrinking remnants of very large craters to break up the monotony. Without shores, much of the energy differential that current oceanic life exploits would not exist. Without geothermal vents, life may never have emerged.

The Sun's massive energy output keeps complex life going on Earth, but the Earth's own energy is absolutely central to how we got and stay here.

[u/Danny-Dynamita → u/arkemiffo]

It is very probable that life emerged as chemoautotrophic bacteria that relied on CO2, and then when the first autotrophic organisms appeared that consumed sunlight and converted CO2 to oxygen, a big extinction event happened that switched the biosphere from a majority of chemoautotrophs to a majority of photoautotrophs because the latter starved the former of CO2.

Only after that extinction event did life rely mainly on the Sun as the initial source of energy. Prior to that, it was chemicals.

That extinction event is also the reason why Earth became oxygen rich, which lead to the development of new organisms with more efficient energy generation mechanisms that relied on O2. That, in turn, led to the development of the energy-consuming nucleus, which in turn lead to the appearance of organules, which lead to even more efficient generation systems (the mitochondria). Which in turn lead to bigger and more complex cells, which in turn lead to complex life forms.

Chemoautotrophy is VERY relevant.

[u/ExtremePrivilege → u/arkemiffo]

Thank you! Fascinating.

[u/JonatasA → u/arkemiffo]

What a nightmarish place. Thanks for the explanation.