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Strange Bacteria Sustains Itself Without Sunlight
Hahnsoo writes "A colony of bacteria found 2.8 kilometers below the Earth's surface in a South African gold mine is able to sustain itself without energy from the Sun. While sub-surface colonies of microorganisms utilizing sulfur (mostly near deep sea hydrothermal vents) is not new, this particular colony is unusual. The colony does it by relying on radioactive uranium to split water into hydrogen gas. Thus, instead of solar energy and photosynthesis, this species relies on radioactive materials and sulfur/hydrogen to facilitate its energy needs. There is some speculation about life on other planets in the article as well."
The thing is, we don't really know what is needed to create life. Assuming that it absolutely cannot emerge in a given environment is, well, unjustified. We have some theories (btw, according to them a somewhat "extreme" environment is actually helpful - it speeds up reactions, and creating organic matter and arranging it into a sort of protoorganism is a bit of a random process) - but that's it.
What's important is that this example shows that we also do not really know what is necessary to sustain life. Some things are obvious - the right kind of solvent, water being almost irreplaceable, some source of energy, etc. However, our understanding of the details is still insufficient. In this case we see that radiation, which is viewed as detrimental to life, even though life can adapt to tolerate it, can actually have an opposite role. Can life emerge with only radiation as an energy source? We don't really know, we can doubt it but we can't exlude it as a possibility. Once it's there, can it survive? Now we know, yes.
This opens new possibilities. For example, we have to be more careful when saying that some kind of object in space cannot support life. With what we learned from this, life could even exist on/in interstellar debris, comets etc., where there is definitely not enough sunlight, as long as there are some radioactive elements there - not too little, not too much, but how can we tell where to draw the line? I'm not saying that life exists in such places, only that now we have to accept such a possibility.
Chernobyl, Windscale, Three Mile Island.
You name three accidents. Chernobyl was admittedly a disaster, but the other two didn't even result in any injuries. So, that's like a grand total of one nuclear disaster. Now, how many people has coal power killed? Hundreds of thousands of miners, perhaps millions more who have suffered from the pollution and - yes - radioactivity released into the atmosphere by coal plants.
Coal power is responsible for more cancer than any nuclear accident ever, including Chernobyl. Think about it.
Thirdly, terrorism. You don't get coal-fired suicide bombers.
You don't get fission suicide bombers either, so what the fuck is your point supposed to be?
Chernobyl, Windscale, Three Mile Island.
Chernobyl was a very serious incident. WHO attributed 56 direct deaths and possibly as many as extra 4000-6000 cancer deaths in the long term. (source 1), (source 2). However, you can't compare the Chernobyl reactor to western reactors of that day and age and certainly not to new types of reactors with passive safety. Three Mile Island is considered to be worlds' second worst nuclear accident. The death toll? 0. Compare that to the thousands of people that die in Chinese coal mines every year. (source)
We're told that current nuclear plants are safe, and not like the ones that exploded or went up in flames. At the time the plants which are now acknowledged to be dangerous were being constructed, the public were also told that they were completely safe. The public can be forgiven for not believing that an industry with a history of serial lies on safety is now both safe and
truthful about it for once.
They ARE safe, even the ones that were being built back then. There is no such thing as 100% safety but the safety record of western nuclear power plants is way better than any other industry. Bhopal anyone?
Also, I don't suppose they were actually intending to have any accidents, or for some of the radioactive leaks - though BNFL's own propaganda admits they deliberately discharged nuclear waste into the sea. Humans make mistakes, which is another reason nuclear isn't trusted.
That's why we need to keep investing ways to make better use of nuclear fuel. A lot of promising research has been done in that area, like the Integral Fast Reactor, which by the way is even safer than contempary reactors.
Thirdly, terrorism. You don't get coal-fired suicide bombers.
It's a lot easier to blow up a refinery, which would cause vastly more damage. Containment buildings are actually built to withstand a 747 flying into it."More than 4,000 coal miners have died in accidents in Ukraine since 1991." Radio Free Europe
Thats Ukraine alone. Worldwide? In China? God knows.
Now for Chernobyl:
"Total eventual deaths due to radiation could reach 4,000, including those of evacuees, a statistical prediction based on estimated doses they received. But, "as about a quarter of people die from spontaneous cancer not caused by Chernobyl radiation, the radiation-induced increase of only about 3 per cent will be difficult to observe". Times of London
Since Chernobyl was by far the worst that death count is close to the number of people killed ever in Nuclear accidents (There were some secret problems in the USSR but no one knows.). Throw in the cancers caused by radiation from soft coal combustion and nukes win hands down as a safe alternative. Okay, the pollution is dirty but it is point source and manageable, whereas CO2 is dispersed and systemic and no one knows how dangerous.
Very frustrating to see how fear of nuclear weapons (a legitimate concern) spilled over into irrational fear of nuclear power.
Nevertheless economic and political forces conspire to prevent the nuclear industry from making a comeback. I think a major political PR initiative is need. Homer Simpson your country calls.
"No fear. No envy. No meanness." Liam Clancy
Bad title, I do realize. It should be "Strange Bacteria Sustains Itself Without Dependence on Photosynthetic-based Food Chain"
all the bacteria in our digestive track surely relies on sunlight for life (tounge-in-cheek)
It isn't that everything else, including the bacteria in your gut, relies directly on sunlight for photosynthesis that it performs iteself, but rather that the entire food chain depends on photosynthesis as the underlying energy-fixating process.
The bacteria in your GI tract rely on the food you eat, which is either plants (photosynthetic autotrophs) or animals (heterotrophs feeding on photosynthetic autotrophs).
Every part of life that you are used to ultimately depends on photosythesis as the source for the energy in the food chain.
Exceptions are rare, which is why this is interesting. Chemosynthetic organisms (such as archaea and other extremophiles), are found near deep sea hydrothermal vents, using geothermal heat as the source energy. These South African bacetria are a second type of chemosythetic ecosystem.
It appears that these newly discovered bacteria in South Africa are chemotrophs using hydrogen and sulfates, with radiation being the underlying energy source, with no underlying food-chain-based dependency on photsynthesis.