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Dartz
2012-Feb-21, 01:19 AM
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?

redshifter
2012-Feb-21, 01:59 AM
Depends. Do they come with extraterrestrial ketchup and mustard? :D Sorry, couldn't resist.

Jens
2012-Feb-21, 02:24 AM
There are some answers (scroll down) in this thread (http://www.bautforum.com/showthread.php/119627-alien-sushi-ethics?). I think the ultimate answer is, we might or might not be able do, depending on a number of factors.

Hornblower
2012-Feb-21, 02:33 AM
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.

eburacum45
2012-Feb-23, 10:19 AM
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.

ggremlin
2012-Feb-23, 11:51 AM
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.

Ara Pacis
2012-Feb-23, 09:36 PM
My question is: Would chirality be important to digestion?

eburacum45
2012-Feb-24, 12:42 AM
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.

BioSci
2012-Feb-24, 12:50 AM
My question is: Would chirality be important to digestion?

My first, general, reaction would be yes.
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.

swampyankee
2012-Feb-24, 01:15 AM
Is this covering the same territory as this thread (http://www.bautforum.com/showthread.php/119627-alien-sushi-ethics?highlight=sushi)?

Ara Pacis
2012-Feb-24, 07:33 AM
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.

Swift
2012-Feb-24, 02:27 PM
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.
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.

Trakar
2012-Feb-24, 05:20 PM
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.

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.

aquitaine
2012-Feb-24, 09:00 PM
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)?

eburacum45
2012-Feb-24, 10:03 PM
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.

Trakar
2012-Feb-24, 10:45 PM
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)?

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.

Trakar
2012-Feb-24, 10:59 PM
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.

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.

Xibalba
2012-Feb-26, 01:36 AM
There are some answers (scroll down) in this thread (http://www.bautforum.com/showthread.php/119627-alien-sushi-ethics?). I think the ultimate answer is, we might or might not be able do, depending on a number of factors.

This is pretty much it. Extraterrestrial life might as well be made of antimatter.

Nick Theodorakis
2012-Feb-26, 01:46 AM
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.

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

aquitaine
2012-Feb-26, 02:11 AM
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


Without help anyway.

JCoyote
2012-Feb-26, 10:39 PM
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... :)

Inclusa
2012-Mar-05, 05:37 AM
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.

Jens
2012-Mar-05, 06:19 AM
Extraterrestrial life might as well be made of antimatter.

That would add a whole new dimension to the concept of "heartburn".

eburacum45
2012-Mar-05, 01:15 PM
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. 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/Hypothetical_types_of_biochemistry#Non-water_solvents

Inthedesert
2012-Mar-05, 03:12 PM
This begs the question, could extraterrestrials eat humans?

Jens
2012-Mar-06, 02:59 AM
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.

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.

ravens_cry
2012-Mar-06, 07:32 AM
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.
It provides usable energy to the human body and contains compounds with carbon that are derived from living sources.
Sounds organic to me.

Inclusa
2012-Mar-06, 09:37 AM
It provides usable energy to the human body and contains compounds with carbon that are derived from living sources. Sounds organic to me.

Thank you! I guess all (if not most) of our foods are organic anyway.

ravens_cry
2012-Mar-06, 09:43 AM
Thank you! I guess all (if not most) of our foods are organic anyway.
If water counts as food, that's about the only one I can think of off hand.

Colin Robinson
2012-Mar-11, 09:58 AM
If water counts as food, that's about the only one I can think of off hand.

Perhaps salt (NaCl) might also count as a food that is inorganic?

ravens_cry
2012-Mar-11, 11:50 AM
Perhaps salt (NaCl) might also count as a food that is inorganic?
Good point. It is generally an ingredient more than a food, while water is enjoyed on its own, but that's pretty much semantics.

swampyankee
2012-Mar-11, 12:05 PM
In, if I remember, the "Starfarers" series of SF novels by Vonda McIntyre, pure water was considered the only "food" item that was universal.

Arneb
2012-Mar-11, 01:42 PM
Good point. It is generally an ingredient more than a food, while water is enjoyed on its own, but that's pretty much semantics.

My chemistry education told me that the chemistry of all carbon-containing compounds is "organic chemistry", excluding carbon itself, CO and CO2, therefore water, salt, minerals are all "inorganic" - which doesn't preclude theri being necessary for life.

Re. the origin of stuff in our food - there is no synthetic organic chemistry (that is, starting with water, CO2 and energy) relevant to the production and processing of food. IOW, all our nutrition is based on other organisms. Even most of today's organic chemistry that has nothing to do with foods (i. e. plastics, rubbers...) starts with the remnants of living organisms: Petrol oil.

Re. the pallatability of alien life forms: Of course, any one of them could happen to be toxic - no big deal, we know that from our own biosphere. Then they could ALL be toxic if they happened to for example use amino acids in their proteins that are toxic to terran organisms (take indospicin (http://de.wikipedia.org/wiki/Indospicin), for example). Another possibility is that they might not be toxic, but non-nutritious. Some of their fat or sugar chemistry might employ chemicals bounds for whose breakup we have no matching enzymes. That is known on Earth, too - cellulose is nothing but polymeric glucose, yet humans cant't digest it.

IIRC, Buzz Aldrin and his coauthor John Barnes turned this into a plot device in "Encounter with Tiber": The ETs visiting Earth find they cannot use the products of our biosphere for food because something in the amino acid composition doesn't match. Therefore, the Tiberians abandon their plans of colonising Earth.

Romanus
2012-Mar-11, 07:27 PM
To restate what I said in the other thread: I think it's extremely unlikely. It's not just protein chirality; why should all proteins even with the right chirality be edible? How many different proteins could be made with say, the exact same molecular formula as hemoglobin or insulin? How many isomers of common carbohydrates? I don't think the body would "recognize" these at all, and would (at best) flush them out.

Zo0tie
2012-Mar-11, 07:57 PM
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?

Eating aliens possible? It would vary from person to person.

Arneb
2012-Mar-11, 09:27 PM
To restate what I said in the other thread: I think it's extremely unlikely. It's not just protein chirality; why should all proteins even with the right chirality be edible? How many different proteins could be made with say, the exact same molecular formula as hemoglobin or insulin? How many isomers of common carbohydrates? I don't think the body would "recognize" these at all, and would (at best) flush them out.

I think that's entirely possible, and to be honest, there are no data to argue against your point. However, two points. I seem to remember (and have been unable to find it in an online search) that some investigation found that certain clay minerals that could have been acting as primordial catalysers would appear to favour L-amino acids ovre D-amino acids - maybe there is a sound chemical basis to Earth's choice of chirality which is above just chance.

Second, it is probably no accident that all the 20 amino acids of the terran genetic code are relatively simple ones and fall into a few easily identifiable classes. I don't think ETs would consist of 20 totally different aa's, so some kind of nutritional value is at least conceivable. However, the possibility of showstoppers existing in the ET biochemistry are probably endless.

So we should probably invent a way to make our food from CO2, H2O, trace elements, and electricity, if we ever want to go to the stars. Yummy. But it should beat seeing your entire hydroponic culture fall prey to one nasty fungus...

JCoyote
2012-Mar-12, 06:23 AM
So we should probably invent a way to make our food from CO2, H2O, trace elements, and electricity, if we ever want to go to the stars. Yummy. But it should beat seeing your entire hydroponic culture fall prey to one nasty fungus...

You'll also need nitrogen. One of my longer term writing projects has an idea for "emergency rations" that are made out of available interstellar materials. I imagined them as being something like a jello or pudding cup, and functional but not popular for long term usage for both morale and ecological purposes.

For colonization you ultimately want to transplant your own compatible biosphere... and for longer term space travel carry enough of it with you.

Inclusa
2012-Mar-12, 07:15 AM
Are you talking about sustainable space colony?!

Noclevername
2012-Mar-12, 07:42 PM
Are you talking about sustainable space colony?!

If it's not sustainable, it wouldn't be a colony.

Romanus
2012-Mar-12, 10:36 PM
In my op, the only way to get around the problem is to bring our own food--that is, our own agriculture--with us. Yes, this unfortunately entails introducing species that may, over evolutionary timescales, completely overwhelm and alter an alien planet's biosphere; I think this grim choice will eventually confront any spacefaring descendants of ours.

Inclusa
2012-Mar-18, 07:23 AM
In my op, the only way to get around the problem is to bring our own food--that is, our own agriculture--with us. Yes, this unfortunately entails introducing species that may, over evolutionary timescales, completely overwhelm and alter an alien planet's biosphere; I think this grim choice will eventually confront any spacefaring descendants of ours.

It is a tragedy to "destroy" another planet's biosphere, but perhaps we can live in a contained environment? Even "habitable planets" may not be absolutely
human-friendly.

swampyankee
2012-Mar-18, 01:29 PM
The closer to "human-friendly" an alien planet's biosphere, the more likely that there will be things there that can kill us: not so much predators, but parasites, environmental toxins, prions, diseases....

SkepticJ
2012-Mar-20, 03:37 AM
In my op, the only way to get around the problem is to bring our own food--that is, our own agriculture--with us. Yes, this unfortunately entails introducing species that may, over evolutionary timescales, completely overwhelm and alter an alien planet's biosphere; I think this grim choice will eventually confront any spacefaring descendants of ours.

There are two obvious possibilities that occur to my mind:

Don't colonize planets with preexisting biospheres. It makes more sense to just manufacture habitats in space--no gravity well to climb out of, and the other sub-optimal properties of planets.

Stop being biological. Then the only food one needs is energy, say in the form of electricity. Got light, hot and cold, or hydrogen? Good to go. They could live in hard vacuum, if they so desire. Or even less hospitable environments.

BigDon
2012-Mar-20, 07:59 PM
I recall a far future sci-fi story where more than 30 or 40 light years from Earth and you ran out of sources of cholesterol, edible sodium chloride (and caffiene!) as other races built on different schemes dominanted.

BigDon
2012-Mar-20, 08:08 PM
Allergies come to mind.

Metabolic clogging of important pathways.

Odd sugars that cleave into toxic substances. (A common garden plant has sugars that are specifically taken up by the heart muscles of mammals. Then once the part the cell wants is cleaved off, the left over is a molecule of hydrogen cyanide. (Nice trick, huh?)

Even humans showing up on Earth from somewhere else would have to learn what they could eat and what they couldn't.

ravens_cry
2012-Mar-23, 05:47 AM
Well, yeah, except for fruit, no plant part wants to be eaten, and in the case of capsicum peppers, not everything that wants to be eaten wants to be eaten by mammals.
Of course, being humans, we cheat. We took a plant (http://en.wikipedia.org/wiki/Cassava) that can very toxic and found a way to process it into a staple.
Assuming very large similarities between them and us, we just might find a way to make some of the alien plants and animals, assuming they have such categorizations, edible.

Trakar
2012-Mar-24, 05:36 PM
Well, yeah, except for fruit, no plant part wants to be eaten, and in the case of capsicum peppers, not everything that wants to be eaten wants to be eaten by mammals.
Of course, being humans, we cheat. We took a plant (http://en.wikipedia.org/wiki/Cassava) that can very toxic and found a way to process it into a staple.
Assuming very large similarities between them and us, we just might find a way to make some of the alien plants and animals, assuming they have such categorizations, edible.

If we are talking about travelling out to other biosystems, rather than importing from other biosystems, it would seem easier and more productive to modify the human rather than modifying the food or biosystem.

ravens_cry
2012-Mar-25, 07:55 PM
I'm not sure how cooking would be harder than genetically engineering humans to a specialized roll.

Inclusa
2012-Mar-26, 04:37 AM
SkepticJ is really into developing the non-biological version of human.

ravens_cry
2012-Mar-26, 08:10 AM
It skeeves me out a little their* enthusiasm. I personally don't think for the foreseeable future it would be any improvement.
*as a gender neutral pronoun.

Trakar
2012-Mar-26, 03:00 PM
I'm not sure how cooking would be harder than genetically engineering humans to a specialized roll.

Hmmm, contaminate a pristine alien biological environment with a lot of foriegn biomass (not just the plants and animals we will eat, but all the microorganisms and nutrients they need to support their health and growth and tolerate the alien environment) or modify the humans to be able to eat and interact without detriment within the native habitat...I'll stand by my assessment.

ravens_cry
2012-Mar-26, 08:10 PM
Leech out the poison by soaking and replacing the water several times, boil until it breaks down into a non-toxic form, leave to rot in the frozen permafrost until it's, technically, edible, humans have a long experience with making the toxic edible.

ravens_cry
2012-Mar-26, 08:11 PM
Leech out the poison by soaking and replacing the water several times, boil until it breaks down into a non-toxic form, leave to rot in the frozen permafrost until it's, technically, edible, humans have a long experience with making the toxic edible through the art and science of cookery.

SkepticJ
2012-Mar-26, 08:54 PM
It skeeves me out a little their* enthusiasm. I personally don't think for the foreseeable future it would be any improvement.
*as a gender neutral pronoun.

Are we going to encounter extraterrestrial ecosystems in the foreseeable future?

Unless Europa has native life, or some chemosynthetic bacteria are munching on rocks, or whatever, in the crust of Mars, or some other locale within our Oort cloud, then it could be centuries, even thousands of years, before we encounter alien life in person. I can't reasonably conceive that humans would have interstellar travel capability without also having advanced robotic technology; it's more inconceivable to me than that humans would make it to Mars on vacuum tube computers.

I'll belabor this no further in this thread.

eburacum45
2012-Mar-26, 11:02 PM
I suspect that, because of chirality, at least half of all alien biochemistry will be indigestible to us; in fact I would expect the majority of biospheres will be largely inedible, no matter how much you cook the organisms concerned. Most compounds that don't kill us would be only useful as roughage, (unless some sort of genetic engineering is employed). Radical engineering might allow us to digest alien compounds directly, or engineered gut flora might do the job. Probably it would be a bit of both. By the time we encounter any alien proteins we will probably have relatively advanced biotechnology that would make this possible, or we may have passed entirely beyond the biological phase.

Trakar
2012-Mar-27, 03:18 AM
I suspect that, because of chirality, at least half of all alien biochemistry will be indigestible to us; in fact I would expect the majority of biospheres will be largely inedible, no matter how much you cook the organisms concerned. Most compounds that don't kill us would be only useful as roughage, (unless some sort of genetic engineering is employed). Radical engineering might allow us to digest alien compounds directly, or engineered gut flora might do the job. Probably it would be a bit of both. By the time we encounter any alien proteins we will probably have relatively advanced biotechnology that would make this possible, or we may have passed entirely beyond the biological phase.

GE gut flora is probably going to make an appearance long before we encounter alien biotic environments, with a push, such could be available within the century, and would vastly alter and increase our food supply options and issues.

Inclusa
2012-Mar-27, 06:40 AM
Are we going to encounter extraterrestrial ecosystems in the foreseeable future?

Unless Europa has native life, or some chemosynthetic bacteria are munching on rocks, or whatever, in the crust of Mars, or some other locale within our Oort cloud, then it could be centuries, even thousands of years, before we encounter alien life in person. I can't reasonably conceive that humans would have interstellar travel capability without also having advanced robotic technology; it's more inconceivable to me than that humans would make it to Mars on vacuum tube computers.

I'll belabor this no further in this thread.


Thank you for this realistic comment!

lone77star
2012-Mar-27, 02:15 PM
There are some creatures and plants on this planet you wouldn't want to eat. Some are poisonous. And it may turn out that some sweet looking fruit hanging from an alien tree might want to eat you back! Ouch!

Jens
2012-Mar-28, 01:07 AM
There are some creatures and plants on this planet you wouldn't want to eat. Some are poisonous.

You mean there are poisonous things on the earth?

ravens_cry
2012-Mar-29, 09:59 PM
There are some creatures and plants on this planet you wouldn't want to eat. Some are poisonous. And it may turn out that some sweet looking fruit hanging from an alien tree might want to eat you back! Ouch!
Then they aren't fruit, as fruit wants to be eaten.
Of course, alien fruit will have strategies to be eaten by the right thing, like capsicum in hot peppers, but want to be eaten all the same.
Also they are much, much more efficient at turning sunlight into chemical energy, I doubt anything we would call a plant would be that kind of a threat.

SkepticJ
2012-Mar-31, 12:41 AM
Also they are much, much more efficient at turning sunlight into chemical energy, I doubt anything we would call a plant would be that kind of a threat.

Maybe.

There are carnivorous plants that consume animals for chemical elements that are lacking in their soil or water environment. Instead of enveloping prey, which limits the size of the prey that can be captured, what if an alien plant had spines that were freakishly poisonous? Something of the order of potassium cyanide.
Bump into the plant and you're screwed. You drop, rot, and fertilize them.

If their poison of choice would work on humans effectively would be blind chance.

ravens_cry
2012-Mar-31, 01:26 AM
I am aware of carnivorous plants and how and why they do what they do.
Poisons, whatever fiction may have you believe, take time to work. Even if the end result is inevitable death, it does the plant no good if you've staggered a hundred feet or more away before dropping dead.
Even insane doses of radiation take time to kill you.

SkepticJ
2012-Mar-31, 03:16 AM
I am aware of carnivorous plants and how and why they do what they do.
Poisons, whatever fiction may have you believe, take time to work. Even if the end result is inevitable death, it does the plant no good if you've staggered a hundred feet or more away before dropping dead.
Even insane doses of radiation take time to kill you.

Less than a gram of potassium cyanide can kill someone dead in just a couple of minutes. They might have about thirty seconds of consciousness out of that, maybe. Not a whole lot (http://en.wikipedia.org/wiki/Cyanide_poisoning) of staggering away is going to happen.

We don't really know how large the alien plant is. Maybe it's a clonal colony that is spread over hectares, like a banyan tree or water hyacinth. Maybe it doesn't matter too much that the plant doesn't directly benefit from the nutrients--another member of its species, perhaps a daughter plant, would benefit. And it could benefit from the animal poisoning they do.

Maybe the plant works like a living punji stick pit. Or entangles legs with hooked-barb covered high tensile strength vines--living barbed wire.

ravens_cry
2012-Mar-31, 08:57 AM
That's a bit of a sticky wicket then, because for it to get big enough to catch human sized prey and make use of them if they run, it needs to be big enough to catch human sized prey if they run, which presumable means they have plenty of nutrients in order to get that big.
Living barbed wire might be an option, lord knows the dangers of descending into a particularly thick blackberry patch, but we're not talking about aggressive fruit than are we?

swampyankee
2012-Mar-31, 05:39 PM
Most of the insanely poisonous creatures, at least, make it very obvious that they're dangerous. Not being eaten is the key to survival, not killing the one that does the devouring.

Ara Pacis
2012-Apr-01, 02:20 AM
It could be a large pitcher-plant type. As for poisoned barbs, perhaps it could have a similar method of rapid poison as a jellyfish.

publiusr
2012-Apr-09, 10:03 PM
So we are talking pink slime from the Green Slime? Sorry, I had to go there...

iloveouterspace
2012-May-01, 12:36 AM
aliens are said to be bacterial-Like creatures with big black slanted eyes and big heads with green-like bodies and yellowish-like bodies but they would probably have to test dogs and cats first and supervise them to see if there's a possibility that we could eat aliens and other life forms but there was a UFO crash in Roswell,new Mexico on Mac Brazel's farm site mac brazel was a sheep farmer who heard an explosion at night and then he discovered what it was in the morning he jumped in his car and headed to the police station and got them to come over to his farmland.

lok32
2012-May-01, 12:04 PM
Maybe we could, but after all the Sci Fi movies I've seen I definitely wouldn't be the first to try it :)

Ilya
2012-May-01, 08:40 PM
Maybe.

There are carnivorous plants that consume animals for chemical elements that are lacking in their soil or water environment. Instead of enveloping prey, which limits the size of the prey that can be captured, what if an alien plant had spines that were freakishly poisonous? Something of the order of potassium cyanide.
Bump into the plant and you're screwed. You drop, rot, and fertilize them.

If their poison of choice would work on humans effectively would be blind chance.
Here is an algae which does exactly that:

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

And its poison does have (some) effect on humans

Jens
2012-May-02, 03:55 AM
aliens are said to be bacterial-Like creatures with big black slanted eyes and big heads with green-like bodies and yellowish-like bodies but they would probably have to test dogs and cats first and supervise them to see if there's a possibility that we could eat aliens and other life forms but there was a UFO crash in Roswell,new Mexico on Mac Brazel's farm site mac brazel was a sheep farmer who heard an explosion at night and then he discovered what it was in the morning he jumped in his car and headed to the police station and got them to come over to his farmland.

They put periods on computer keyboards are much easier today run-on sentences can be difficult to understand. :)

swampyankee
2012-May-03, 12:08 AM
They put periods on computer keyboards are much easier today run-on sentences can be difficult to understand. :)

Punctuation marks and proper capitalization make things easier to read. I hope he or she doesn't hand me a report typed like that.

Paul Wally
2012-May-03, 02:16 AM
Perhaps if we domesticate the alien animals we could farm with them, and through generations of artificial selection make them more edible.

ravens_cry
2012-May-03, 03:31 AM
Perhaps if we domesticate the alien animals we could farm with them, and through generations of artificial selection make them more edible.
Unless the critters have an astonishingly short generational cycle, people would probably want a quicker return on their investment. If the critter can be processed now into an edible form, and selective breeding just makes that less arduous, or even necessary, it could be a different matter. See Cassava (http://en.wikipedia.org/wiki/Cassava) for example.

eburacum45
2012-May-03, 07:49 AM
If we want to eat the local animals, it might be easier to alter human physiology than to alter all the potential food animals and the food that they eat. Properly adapted humans could integrate into to local biosphere without disrupting it too much. Humans adapt- that's what we are specialised in.

primummobile
2012-May-12, 08:28 PM
According to Jack Haldeman in the short story Lousville Slugger, you only get the right to eat another species after you have defeated them in a series of baseball games. And even after all of that, you may not like the taste of them.

Jens
2012-May-18, 05:36 AM
Perhaps if we domesticate the alien animals we could farm with them, and through generations of artificial selection make them more edible.

If there's something fundamentally incompatible, like for example if their molecules are chirally wrong, then that would be impossible. It's only if they are very close to something edible for us that it would work. We could do the same on earth, so for example breed snakes or spiders to make them more palatable.

But on the other hand, consider this. We've been breeding broccoli and Brussels sprouts for centuries, and we still haven't gotten them edible!

swampyankee
2012-May-18, 10:01 AM
But on the other hand, consider this. We've been breeding broccoli and Brussels sprouts for centuries, and we still haven't gotten them edible!

Gee, I feel the same way about bacon made from pork bellies.

Swift
2012-May-18, 12:52 PM
According to Jack Haldeman in the short story Lousville Slugger, you only get the right to eat another species after you have defeated them in a series of baseball games. And even after all of that, you may not like the taste of them.
So the Indians could have eaten the Mariners, after sweeping them in a two game series. :eek:
Good thing MLB has adopted that rule.

nikkoo
2012-Jun-02, 08:41 PM
The closer to "human-friendly" an alien planet's biosphere, the more likely that there will be things there that can kill us: not so much predators