In elementary school, you were probably taught that photosynthesis is the basis of maintaining life on Earth. The sun shines on green plants. Those plants suck up the sun and carbon dioxide from the atmosphere and grow, "exhaling" oxygen. Animal life then eats those plants and inhales that oxygen for its own survival. Some of those animals become food for humans (I'm looking at you, pigs) and other omnivores/carnivores. Animals exhale carbon dioxide, and the process begins again. The constant is sunlight. When there is no sun, there is no photosynthesis. Plants die, animals die, people die.
But under the sea (cue Sebastian from The Little Mermaid), you eventually will reach a depth where there is no sun. So, if my elementary school teachers were right, then there shouldn't be any life there, just sunken corpses of fish from shallower waters. Those fish eventually turn to limestone and/or oil, but that's another story...
If you are still functioning on sweeping assumptions made in elementary school, you'd be wrong. In 1977, scientists piloted Alvin, a tiny-submarine, to the Pacific Ocean floor and found hydrothermal vents, known by their friends as Black Smokers (and they have no intention of quitting). Now these vents have been found in both the Atlantic and Pacific more than a mile deep and intent on getting the party started.
They raise the temperature to more than 700ºF and lower the pH to about vinegar level, yet there is life. The sun doesn’t shine, and there are crazy hot temperatures and vinegar-like water. It's like a crab feast for vampires. Just bring the hammers. Despite the extreme conditions, some creatures call this home. Archaea and extremophiles use chemosynthesis to convert heat, methane and sulfur to energy. Clams and tubeworms feed on them. They die and are deposited about the base of the smokers and the cycle starts anew.
This is a big shift from the typical ecosystem model.
Why is this important?
We need to know what is possible. Eventually, if Evadot's writers have anything to say about it, the human race is going to take to the stars. When we get there, we need to know that life is possible absent of the sun's loving glances. I'm not saying we're going to run into those things from Independence Day or Mars Attacks! but we may run into stuff we can eat! I don't know about you, but I love eating.
In the more immediate future, what we could learn from these ecosystems is practically limitless because we know practically nothing. Just for starters, are there medicinal properties to archaea and extremophiles? There's even some bacteria down there that use the faint light from the Black Smokers for photosynthesis, that old elementary school buddy of ours. What significance could this bacteria have for the future of the human race?
For me, just knowing there is something out there that is still basically unknown makes it worth exploring. Right now, in the ocean, the future is going about its daily business. Black Smokers are smoking, their second-hand smoke supporting an ecosystem. Scaly-footed gastropods are making shells from pyrite to protect themselves from predatory, toothed snails looking for a clam or tubeworm lunch...
What we don't know may not hurt us directly, but it does hold us back. Put me in the smoking section this time.