What is life expectancy without water

Can there be life without oxygen and water?

Life without oxygen is possible

That is a super exciting question that also preoccupies many scientists. The answer they are giving at the moment is: yes, probably a life is conceivable that functions completely differently from the one we know.

Let's start with oxygen. It is pretty clear that there are forms of life that get by without oxygen - there are also today, namely everywhere where no oxygen can be found, in wetlands or in deep lakes, for example, where the water is fairly still. At a certain depth there is no longer any oxygen, but there are still bacteria there that can do without oxygen.

And one must not forget: The first living things on earth neither had green leaves nor did they need oxygen - on the contrary, oxygen was a waste product and like a poison for them. The plants, but also we humans and animals that use oxygen, came much later. So life without oxygen and green, no question about it, there is.

Water is essential for the life we ​​know

But what about the water? That was always the big question in the Mars missions: is there liquid water? Today we at least know that there were some in the past. And then of course the question arises: If there was water, was there life there too?

For life as we know it, water is absolutely essential. It is the life medium par excellence, it transports nutrients into the organisms and toxins out of them. The question is, is there any other substance that could do the same thing? Maybe somewhere where it is much colder than here, where there is definitely no liquid water.

For example, the planet Saturn has a moon called Titan. It's freezing there, there is definitely no liquid water there, but what there could be would be lakes of liquid methane. And it is quite possible that there are forms of life in which the source of life is not water, but methane.

Environment based on silicon instead of carbon is conceivable

It goes even further: the basic building block of life on earth is carbon. Everything organic - proteins, carbohydrates, fats, right through to our genetic material, the DNA - is, at least the basic structure, made up of carbon atoms. After all, carbon is one of the very few elements that are so versatile that it can build up many highly complex scaffolds and structures. But there is another element that could theoretically do that too: silicon. That is why some biologists consider it possible that a silicon-based environment is at least conceivable. And primarily on other planets.

But there are also researchers to be taken seriously who say: In theory, these forms of life could even exist on earth, perhaps even in our body, only that we have not yet discovered them. We are not talking about green men, but they could be microorganisms that can hardly be distinguished from bacteria on the outside. But if they worked completely differently from the life we ​​know, it would not be so easy to find them among all the other organisms.

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