If humans ever manage to colonize other solar systems in the distant future, and we come across inhabited worlds, could we use the native species on those worlds for food? Would the life have to be DNA-based, or would that not matter?
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If humans ever manage to colonize other solar systems in the distant future, and we come across inhabited worlds, could we use the native species on those worlds for food? Would the life have to be DNA-based, or would that not matter?
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Depends. Do they come with extraterrestrial ketchup and mustard?Sorry, couldn't resist.
Order of Kilopi
There are some answers (scroll down) in this thread. I think the ultimate answer is, we might or might not be able do, depending on a number of factors.
As above, so below
Order of Kilopi
For some types of potential nutrients, it could depend on whether or not their molecules are structurally compatible with our digestive enzymes. That could be analogous to the difference between cis fats, where molecular subassemblies connected by a double bond are on the same side of the main chain, and trans fats, where the corresponding components are on opposite sides of the chain. My admittedly meager understanding is that these molecules connect with the enzyme molecules like a key in a lock, and our enzymes fit better with the cis fats.
Order of Kilopi
All life on Earth is related, and uses similar biochemistry; this would not be true of extraterrestrial life, so only a fraction of lifeforms out there would be edible. How large, or how small, that fraction might be is unknown. I suspect it is quite small, possibly very small. However it may be possible to reduce alien organisms to a nutrient-rich soup and use that to grow some other form of foodstuff that we might eat.
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In space, no one can hear you eat them or them eat YOU.
We eat many things on Earth that have vastly different chemical make-ups from ourselves. Some poisonous, some not. The problem is could we digest and/or extract vitamins, proteins and other items that go into the basic blocking blocks. The basic amino acids would have to be same, I know that others have been discovered in research but the question would be do the ones we know, are they the normal occurring ones. Supplements would probably be required even if we could digest E.T.
Order of Kilopi
My question is: Would chirality be important to digestion?
Et tu BAUT? Quantum mutatus ab illo.
Order of Kilopi
Sure; right-handed amino acids wouldn't be usable by humans to build proteins, and might only be useful when broken down by gut flora into more basic compounds. Eating only right-handed life would make you poorly quite quickly.
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My first, general, reaction would be yes.Originally Posted by Ara Pacis
But it would depend on which specific digestive function you are interested in. Some processes may proceed at normal rates, but many (most?) enzymatic steps would be blocked.
Certainly, complete digestion and metabolism would be improbable at best.
If one where to look at one of those wall-size charts of cellular metabolic steps, the steps that involve a chemical reaction at a chiral center would most likely be blocked by an alt-chiral molecule. And even other (non-chiral linked) enzymatic steps would require the substrates to line up to the reactive sites correctly and alt-chiral compounds may have the R-groups in the "wrong" direction.
Order of Kilopi
Order of Kilopi
And now I'm wondering if similar but different proteins might cause problems, in a way similar to prion diseases. The hypothesis is that a malformed protein causes properly formed proteins to change into the malformed shape on contact. It's kinda like Ice-9 in that way.
Et tu BAUT? Quantum mutatus ab illo.
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On the flip side, even though we all came from the same planet, there are many things on Earth that we can't eat.
Often when I lead hikes, people ask if a particular plant or mushroom is poisonous or eatable. It is not a black and white thing. There are things that are poisonous that will make you a little uncomfortable and there are things that will pretty quickly kill you. On the other side, there are things you can eat, but they will offer you no nutrition at all, and there are things that you can eat that are extremely nutritious. And that's just on Earth.
I would suspect that things like simply sugars and carbohydrates will work just about everywhere in the Universe. Amino acids and proteins have a lot more variability. And then of course are all the trace compounds that might poison an otherwise tasty alien snack.
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Which brings up an interesting point. It might be necessary to colonize our digestive system with some otherwise neutral local bacteria before we could really take advantage of even largely biochemically similar alien foodstuffs.
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If its just a matter of gut flora being able to break it down, what about using microbes genetically engineered for that purpose? Or taking the enzymes needed in pill form (like Lactaid allows lactose intolerant people to consume dairy products)?
Order of Kilopi
One idea I've had is to replace the gut flora entirely with microscopic artificial biotech machines; these would probably be almost identical to bacteria, but designed from scratch to carry out certain predetermined tasks, without having the capacity to evolve into pathogens.
Perhaps I'm being a little optimistic here, but it seems likely to me that artificial gut flora would be among the least impressive of the achievements of future biotechnology. By the time we reach life-bearing exoplanets I would expect our biotech to be extremely advanced. On the other hand we might encounter alien life closer to home, on Mars perhaps, or even the Moon; such a relatively near-future encounter might not give humanity enough time to develop mature biotech.
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Well, there are certainly other issues than just whether or not we possess the enzymes or intermediary bacteria required to break nutrients down into absorbably/usable units, dealing with heavy metals, organic toxins, etc., are an entirely seperate set of issues. But properly designed symbiotic bacteria, could provide a big change in how we look at foodstuffs and nutrition in our own world, without even considering alien biochemistries.
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I would agree that microtech (no nano required) as well as true, engineered, biotech (genetically/molecularly constructed/engineered) are on the near-future horizon. I am rather counting on these technologies to help me reach next century, ...darn recessions.
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This is pretty much it. Extraterrestrial life might as well be made of antimatter.
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This is essentially what animls that digest cellulose do, since no animal (or at least, no vertebrate animal) has the necessary enzymes to break down cellulose into its sugar subunits.
Considering we can't digest most of the biomass on earth makes me think it's unlikely that most of alien biomass would be digestible.
Nick
Established Member
Without help anyway.
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I would doubt anything would be specifically toxic toward us though, and what poisonous things there are would likely be so because of elemental toxicity not protein toxicity. In other words, arsenic containing life would be dangerous to us because of the arsenic, not because its molecules do specific things to ours. Usually. This is mostly based on the fact that most really dangerous toxins in our environment appear to be directly evolved because the toxicity to us was an advantage. A sting from a scorpionlike alien would be likely be non-toxic to us most times. However, I am not going to volunteer to be the test subject...
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By creatures, do you mean all types of organisms? I'm trying to imagine non-organic foods, but these would be candies and soft drinks mostly, and they are mostly non-nutritous.
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Order of Kilopi
That would add a whole new dimension to the concept of "heartburn".
As above, so below
Order of Kilopi
Well, creatures with metabolisms using sulphuric acid or ammonia would probably be instantly fatal if ingested, but we are unlikely to want to share a biosphere with them anyway.
see
http://en.wikipedia.org/wiki/Hypothe...water_solvents
Newbie
This begs the question, could extraterrestrials eat humans?
Order of Kilopi
Aren't candies and soft drinks organic? I think there's a lot of corn syrup and sugar and stuff which is derived from plants. What in candy isn't organic, apart from the water? And isn't candy tremendously nutritious? Not necessarily in a good way, of course, but nutritious nonetheless.
As above, so below
Order of Kilopi
It provides usable energy to the human body and contains compounds with carbon that are derived from living sources.
Sounds organic to me.
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Thank you! I guess all (if not most) of our foods are organic anyway.
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Order of Kilopi
If water counts as food, that's about the only one I can think of off hand.
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Perhaps salt (NaCl) might also count as a food that is inorganic?
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