How are bacteria created?

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Just read a news article about how 3 completely new types of bacteria have been found on the international space station due to it’s isolation, if that’s the case then how did they get there if we have never observed them before? what created them?

In: Biology

Bacteria are alive and evolve just like any other organism, we haven’t closely studied all the millions of different types of bacteria out there to identify them all yet.

Bacteria come from other bacteria. As for where “new” bacteria come from, there are two answers to that:

One, we don’t have a catalog of every type of bacteria that exists. The number of different bacteria that we don’t have a record of probably outnumbers the ones that we do know about explicitly. So sometimes a new type of bacteria is discovered not because it came from anywhere, but because no one noticed it before.

Two, every time a bacterium reproduces, just like anything else, there is a chance the reproduction process will include errors. These errors are mutations, which can change the nature of the bacteria that result. Accumulate enough mutations, and you wind up with, effectively, a new bacteria.

Bacteria reproduce extremely quickly in comparison to most macroscopic life, so changes that would take millennia or longer to happen in most species can take place in a matter of a few years with bacteria.

Some similar bacteria likely travelled up there on the astronauts or some item.

What makes every organism unique is it’s DNA. bacteria change their DNA a lot, it’s why they adapt so fast. If they make a change that makes them unable to survive, those DNA changes will not be passed on. What determines if the DNA changes are good or bad is the environment.

For instance, if some change makes you better at surviving in the cold, but you live in a hot climate, it likely won’t get passed on. In a cold climate, it could be very useful.

The ISS is a very unique environment. Everything is precisely controlled and does not exchange anything with the outside. This would lead to unique DNA changes being passed on.

A similar situation is observed on islands. Before people started moving around so much, taking animals and diseases with them, islands bred unique organisms because they were isolated from each other.

They would have mutated from prior bacteria.

The space station is a good place to observe this…relatively high radiation environment (more mutations), relatively few competitors, very stable temperature/humidity, lots of scientists around to keep watch on things. And bacteria multiple very quickly so they evolve much faster than we do.

They are created the same way most forms of life are created. They multiply and spread around.

To add to the other responses, also note that such simple organisms can evolve very fast due to short generations.

I.e. while a generation for humans is in the ballpark of about 20 years, for bacteria it’s a matter of hours.

And while asexual reproduction does hinder the evolution, if you start with one bacteria and end up with a couple trillion in a matter of months, there ought to be completely new species evolved to survive in the new environment.

The same would happen to any other species, it would just take a lot longer, especially if it’s not artificially tweaked (like when humans bred new dogs for example).

The short answer is that new bacteria are appearing all the time because evolution happens on a generational scale. Bacteria reproduce geometrically, which allows them to go through several generations in the span of a few days, rather than a few centuries. Every generation, there will inevitably be a few bacteria with mutations in their genetic code. Enough of these mutations add up over the course of a few thousand generations, and boom – new bacteria. This happens anywhere bacteria are found, and bacteria are found on humans, which means bacteria will be found in the ISS.

for something to be considered a new species, it has to be unable to reproduce successfully with the original organisms. Let’s say that we have two groups of the same species of bacteria, Bacteria X and Bacteria Y. X and Y are, right now, the exact same species, and can reproduce with one another. Let’s keep X on earth and shoot Y to space, and leave them for a few years. Bacteria reproduce very quickly, and therefore evolve more quickly. Evolution is just random mutations that help survival being passed down from generation, and since bacteria generations are so fast, they can evolve to suit their new environments very quickly. This would happen even if they weren’t in space! Like if we put Bacteria Y in a new climate on earth this would happen too. But now let’s take Bacteria Y out from orbit and compare them to Bacteria X. Y is now so different from X that they can no longer reproduce, and that means that Y is a new species.

To illustrate just how fast bacteria can evolve and adapt, [Here’s](https://www.smithsonianmag.com/smart-news/watch-ecoli-evolve-your-eyes-180960418/) a video of e.coli developing antibiotic resistance.

It’s not *quite* the same as a new species evolving, but helps give an idea of how fast it can happen.

I’m a soil microbiologist and don’t know anything about space bacteria. But my best guess would be: Lots of bacteria from many bacterial species are brought up into space by accident (it’s unavoidable, really). Most of the bacteria probably die in this new environment, but some can survive pretty harsh conditions including the vacuum of space or the inside of the space station. The ones that can survive continue to replicate, and bacterial DNA mutates very frequently as they replicate. So in a relatively short period of time, you have an isolated community of bacteria with a lot of differences in DNA compared to bacteria back on earth. Are these DNA changes functionally significant? Maybe, maybe not.

Outer space aside, If you isolated any strain of bacteria and had it replicate on its own for long enough, it would probably be considered a “new” species before long because the bacteria accumulate mutations and can’t swap DNA with any other strains/species. Because bacteria naturally mutate so quickly and swap DNA with each other all the time, we generally talk about bacteria at the Genus level and don’t fuss with getting as fine-scale as Species too much.

They are simply new strains of species we have and know about here on earth already. They are not new species.

You could think of them like strains of the flu (which is a virus, but the comparison works). It’s still the flu, but has a few new qualities that differ slightly from the original. This is why we have new flu shots every year.

Ehm to explain simply they just evolved from our normal bacteria here on earth

kind of like how humans evolved from “monkey like” creature but since bacteria reproduces in minutes or hours rather than years like us, their adaptation time is really short so they are no longer the original bacteria but a new breed to be short