Advanced Anaerobic Organisms

TruthSeeker

TruthSeeker

Fancy Virtual Reality Monkey
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Is it possible for anaerobic organisms to become advanced? That is, develop "intelligence"? How would they look like (in terms of chemical composition)? How would their organs and systems be composed?

Any ideas? :scratchin:
 
Depends on what you consider intelligence. But since most macro-organisms use O2 as their terminal electron acceptor, and it is known to provide the best yield for respiration. Plants are kinda anaerobic in the sense that they only produce O2, and do not consume it. There is talk of Si based organisms, but in theory they would be much heavier, and complex macrolife is difficult to predict. Most macrocreatures require O2 on a cellular level.
 
This makes me wonder what the largest anaerobe is? Anyone know?

There are things with greater oxidative potential than O2, but none that I'm aware of any organisms using for respiration.
 
IIRC Goldfish can survive for a long time - months - without oxygen.

But the planet spent about two billion years covered with simple living things in oxygen free environments without anything more complex than a tube worm evolving, apparently (hmmm. wonder about that), so the evidence is that there is some large advantage in oxygen metabolism.
 
Most plants actually respire aerobically. Quite a number of animals, including worms but also some vertebrates are able to undergo periodic anaerobiosis, however I am not aware of any that are primary anaerobes. The largest real anaerobes are probably fungi.
 
And fungi can be quite big. The biggest living being in the planet is a fungi. So why don't we have more anaerobic beings around? :shrug:

Did we eat an anaerobic animal at some point in our existance? Is that why they are not around? :D
 
Here's a bit about anaerobic respiration:

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

Now, why is that not used in macroscopic animals? The same with plants! Why there are no animals that also use photosynthesis? Those methods of gathering energy are quite powerful and independent. So why nature didn't evolve that way? :shrug:
 
In ecology we learn that there is an advantage to being a higher order heterotroph - you don't have to gather food as often. Your "energy source" is a rich source and more time can be spent in pursuit of other things. However, the plant is constrained in the same manner that the primary consumer is constrained - the food source is a poor quality and so a lot of time must be spent gathering food. (Cows graze for example.)

Photosynthesis is a good method to acquire energy (and the way energy is ultimately harvested for everything else - so inarguably necessary) but it is not, perhaps, the most efficient. Maybe less ATP is used to chew a bite of steak then to make the sugars that the cow had to metabolise into meat.

It only takes a quick look at cellular respiration to see that the aerobic pathway has a higher payload of energy than the anaerobic (fermentation (anaerobic): max 2 ATP; cellular respiration (aerobic): 36 ATP). So, why are more organisms using aerobic respiration? Truth is in the numbers - micro or macroscopic.

As for developing intelligence - first you have to come up with a definition of intelligence that can be quantified and measured. Then we can explore the question.
 
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As mentioned above, anaerobic respiration is extremely inefficient. It makes sense for a limited amount of time or for specialized tissues (e.g. lactic acid fermentation in muscles), but overall aerobic respiration is preferred, if possible. As of why there is no photosynthesis in animals: motility costs a lot of energy.
 
So photosynthesis and fermentation doesn't release much energy.... yeah, that explains...
 
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