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How should a non-cellular metal organism maintain homeostasis?

  1. Dec 15, 2011 #1
    So, I'm drafting out a science fiction being. It's a bipedal, anaerobic, autotrophic sentient being that is almost entirely mechanical and it has no DNA or cellular structure - instead, it's physiology is a maze of gears and metal mechanisms (although they do store information somewhat digitally) almost all the way down to the microscopic level.

    They're made completely of various metal alloys and they live on a planet made of carbon. Petroleum lakes cover 70 percent of the planet's surface and they use it to maintain smooth joints. The surface of the planet is covered in various metal alloys. The atmosphere is rich in various gasses, some of which are flammable.

    The beings have only one purpose - to create others of their kind. Because they have no cellular structure - no way of physically reproducing - they opt for a different option, assembling others by hand. It can take hundreds of years but in the end, the gain is greater because the beings have no natural predators. Not only this, but each being adds new function to its creation, thus sustaining a form of artificial evolution, you might say.

    The main issue I have in designing the species is its metabolism. How do they gain energy? Metal cogs and gears that make up an entire organism would surely require a steady and powerful source of energy. My first thought was that the surface of the beings planet was covered in thick layers of powerful gas (such as nitrogen) that they would absorb to maintain homeostasis. There are two issues that I can think of. First, the beings need an almost constant source of fuel and gas vapors could be sparse in some areas and overly thick in others. I came up with a temporary solution to this – the planet has no wind so gas is evenly distributed throughout its surface. The flip side is that an area wherever a being has been is a “dead zone” because the being has used up some of the gas there and it lacks enough gas to maintain any other life forms.

    Second, how would the being use the fuel? I originally imagined that it would absorb the gas through porous holes and then turn it into energy from controlled combustion processes (similar to cellular metabolism). There might be problems with this as well. For example, would the organism damage any of its components during the process? If a cellular organism was to kill itself due to an accident, it could easily be replaced. But when a non-cellular organism has thousands of irreplaceable parts, a single accident could prove to be fatal.

    So, what are your thoughts? Is it an organism that could live with a little faith? I'm open to criticism.
  2. jcsd
  3. Dec 15, 2011 #2
    1. I don't get it - how does that guarantee they have no natural predators? Or, how does that take advantage of the fact that they have no predators?

    2. If they have no DNA or other genetic material, why would they want to reproduce? What's the evolutionary or other drive for them to work hard and create progeny?
  4. Dec 15, 2011 #3
    I've decided to call the beings the Replicators.

    They have no predators so they only die after their parts wear out and become unusable. It takes about one lifetime to create a new Replicator so the ratio is an accurate 1:1 ratio.

    By the way, I falsely stated that they had no natural predators. Instead, I should have said that they have no predators altogether. It would probably make more sense for me to make them have predators so they have a stronger will to reproduce and survive.

    I haven't thought about that yet much, but their minds are digital so it's quite possible for that information to be programmed into them. That would suggest that some other being, a creator of some sort, programmed the information into them. I'm assuming that happened because it's impossible for non-cellular life to evolve in such a manner.

    The Replicators are basically just intricate Von Neumann machines whose only purpose is to create others of their kind and heighten their physical evolution.
  5. Dec 15, 2011 #4


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    I take it these are artificial machines? There's no way a set up like this could evolve. A few thoughts;
    • How to they replicate? You say assemble by hand but how to they build new components?
    • How do they self repair?
    • What allows them to think and plan?
    • Where and how is information stored and accessed?
    Considering the huge complexity of natural organisms I don't see how an organism made out of simple cogs could ever act like an animal. You say they are anaerobic and autotrophic but both of these involve the synthesis and use of organic molecules.

    Edit: Also;
    • A planet made from carbon that has metals on the surface?
    • Where did the oil come from if it wasn't produced by organic life?
    • Why does this planet not have wind? How is nitrogen (an inert gas) powerful fuel?
    • What stops the machines from just using up all the fuel?
    Last edited: Dec 15, 2011
  6. Dec 16, 2011 #5
    I'm sorry, but that doesn't really make much sense. What does heighten their physical evolution mean, and why would it be so? Living beings don't live in order to evolve, and individuals don't evolve; populations do. And evolution is never a purpose.

    I also second all of ryan_m_b´s points. I think you have a nucleus of an idea here, but it seems that your knowledge lies in CS, not in biology. You have to elucidate many of the evolutionary details, as well as create a convincing genesis story for your world and for your Replicators.
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