WI: The Oxygen Disaster

Alright, first off, I am not certain if this is the correct place to create this thread so if it isn't the right one then I apologize. I'm new :D

Anyways, I digress.

A couple of days ago I was watching this really interesting documentary, the Journey of Life, the first episode, concerning The Seas. In other words, the start of all life and one of the biggest events, the Oxygen Disaster (It was called something like that if I recall correctly).

Anyways, here's my thought. The stromatolites, the first organisms, created almost a mass extinction by releasing a poison, oxygen. The question is really simple however.

How would life evolve if stromatolites never came to existance? If life would evolve without the oxygen? Would everything be doomed to go extinct and would Earth remain as an empty rock floating in space? Or would life adept to the circumstances and could we see an entire alien planet?

Now I know this is a bit ... early, since the Precambrian eon wasn't exactly yesterday, but give some thoughts, some ideas.

My thanks in advance.
 
Alright, first off, I am not certain if this is the correct place to create this thread so if it isn't the right one then I apologize. I'm new :D

Anyways, I digress.

A couple of days ago I was watching this really interesting documentary, the Journey of Life, the first episode, concerning The Seas. In other words, the start of all life and one of the biggest events, the Oxygen Disaster (It was called something like that if I recall correctly).

Anyways, here's my thought. The stromatolites, the first organisms, created almost a mass extinction by releasing a poison, oxygen. The question is really simple however.

How would life evolve if stromatolites never came to existance? If life would evolve without the oxygen? Would everything be doomed to go extinct and would Earth remain as an empty rock floating in space? Or would life adept to the circumstances and could we see an entire alien planet?

Now I know this is a bit ... early, since the Precambrian eon wasn't exactly yesterday, but give some thoughts, some ideas.

My thanks in advance.
Well, if you don't have oxygen, you don't have multi-cellular organisms, at least none more complex than strings of cells.

What you would have would be colonies of bacteria, and nothing more. (Certainly, you'd have sulfur bacteria which use H2S instead of H2O in their photosynthesis.)
 
I'm certainly no expert, but biochem is my intended major and I find this type of thing extremely interesting, so I'll try to answer.

I'm thinking that realistically, if the algaes that eventually formed stromatolites didn't become photosynthetic, some other organism would, simply because the sun is too good of a source of energy to be passed up forever. It seems like eventually some microorganism would mutate to use sunlight, but of course that isn't guranteed. I'm not sure if there could be a chemical process that uses solar energy without releasing oxygen, but I'll leave that up to an actual chemist to answer.

In a world without oxygen, only anaerobic organisms would exist, which means that life would probably never evolve beyond simple single celled organisms. Of course, some other process which produces a comparable amount of energy to aerobic respiration might evolve. You can't really say one way or the other.

By the way, I personally think that scenarios like this should go in this forum, but some other people say that they should go in ASB. I think at this point that issue hasn't really been settled.

Edit: How could I forget, welcome to the board!
 
Well, I was quite wrong on this one then I see. I knew oxygen was necessary for advanced life, but I presumed that was only because we evolved from the creatures that adapted to oxygen.

Basically put I had this image of some alien species that didn't need oxygen and had other weird ways of surviving. It's a pity though, because it could have been interesting.

Anyways, is there truly no way at all that a species can become advanced and even sentient without oxygen?

And thank you by the way for the welcome Nova :D I've been lurking on these boards for quite some while (Love the various timelines here). Since I finally saw something worthwile to contribute I just made an account.
 
Well, I was quite wrong on this one then I see. I knew oxygen was necessary for advanced life, but I presumed that was only because we evolved from the creatures that adapted to oxygen.

Basically put I had this image of some alien species that didn't need oxygen and had other weird ways of surviving. It's a pity though, because it could have been interesting.

Anyways, is there truly no way at all that a species can become advanced and even sentient without oxygen?

And thank you by the way for the welcome Nova :D I've been lurking on these boards for quite some while (Love the various timelines here). Since I finally saw something worthwile to contribute I just made an account.

How do you get an organism that has enough energy to move around (an 'animal') without oxygen? Where do they get their energy from? Forget about 'civilization', just movement requires more energy than plants have.
 
How do you get an organism that has enough energy to move around (an 'animal') without oxygen? Where do they get their energy from? Forget about 'civilization', just movement requires more energy than plants have.

Umm... Technically, it might be possible for plants to produce lumps of sulfur that *animals eat and use to metabolize the plant material. Again, technically, you could have energy stored in say triple bonds (e.g. cyanide) which would release energy breaking down to single bonds. But neither of these would likely provide enough energy for any organism more active than an OTL sloth (at a guess). Intelligence would be REALLY difficult.

And various science fiction tales have had chlorine/fluorine breathers instead of oxygen breathers, but the problem is that there is WAY more oxygen in the universe than chlorine or fluorine.

So, ya, I'd say oxygen is pretty much a necessity.
 
Do all plants 'breath' Carbon-Dioxide and 'exhale' Oxygen? Is there no way to make a plant exhale something other than oxygen and then all animal life adapt to inhale the 'new' gas instead?

Isn't Thande a chemisty type guy? He might know the answer.

:)
 
I don't think it would be impossible to have an anaerobic multicellular organism. However, due to the electron acceptors, oxygen respiration provides the most energy by far (perhaps an order of magnitude). As a result, oxygen will always be favored as the primary gas cycle for life. And anaerobic life will always be really, really slow.
 

Keenir

Banned
How do you get an organism that has enough energy to move around (an 'animal') without oxygen? Where do they get their energy from?

where do most jellyfish get their energy from? (oh, right, they drift and float)

...and the rest is from their food - be it other organisms, or (with non-jellyfish) from chemosynthesis.


And anaerobic life will always be really, really slow.

as with the joke about the two guys and a bear, you only need to be faster than your rival.
 

Michael Busch

By the way, I personally think that scenarios like this should go in this forum, but some other people say that they should go in ASB. I think at this point that issue hasn't really been settled.

I agree with Nova on this - geological and biological PODs need to be separated from the historical and ASB.

Re. the OP and trying to recall the geobiology material I've been exposed to:

There are productive anaerobic pathways, but reacting carbon dioxide and hydrogen-bearing compounds (most importantly water) almost always produces oxygen as a waste product (particularly of photosynthesis of water and carbon dioxide). Once we run out of sinks for the oxygen (dissolved iron in the ocean, methane in the atmosphere), it must build up and once it does, aerobic metabolisms win out.

Given primitive life and the initial composition of the Earth, an oxygen-bearing atmosphere seems inevitable once primary production climbs past a certain point.
 
Well, I was quite wrong on this one then I see. I knew oxygen was necessary for advanced life, but I presumed that was only because we evolved from the creatures that adapted to oxygen.

Basically put I had this image of some alien species that didn't need oxygen and had other weird ways of surviving. It's a pity though, because it could have been interesting.

Anyways, is there truly no way at all that a species can become advanced and even sentient without oxygen?

And thank you by the way for the welcome Nova :D I've been lurking on these boards for quite some while (Love the various timelines here). Since I finally saw something worthwile to contribute I just made an account.

You're very welcome for the welcome:D

I do think that you could have anaerobic organisms that would be complex and multicellular, I just think that it'd be very unlikely for them to evolve on Earth. The chemical make up of the planet and the usefulness of oxygen and sunlight for biological processes make it pretty unlikely for alternative complex organisms to evolve (and compete sucesfully) here.

That being said, people smarter than myself have come up with possible alternative biologies, although I haven't seen any as radical as what you're proposing. I remember reading about one in which arsenic was used instead of phosphorous. I'm sure you've come across the (In my uneducated opinion unlikely) idea of silicon based life.

Here's a wikipedia (yes, I'm using it guys!) link to a list of the ideas that are floating around out there. I have no idea how valid any of them are, but I figure it's a good place to start looking (and a fun read if you're as nerdy as me).

http://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry

Edit: I haven't looked into the thing it mentions about dust, and I refuse to look it up because I'm going to pretend that this is the first step to energy beings.
 
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Those anaerobic bacteria are still swirling around in my stomach. They get quite active every time I fart.
That said I would recommend reading up on what anaerobic bacteria are and how they reproduced. This might give you some basic insight to how they would get energy. (Coffee for example would be poison to them). You might find a few pure scifi forums to see if any similar ideas are out there.
 
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