View Full Version : Life as we know it...or don't know it ?

2003-Sep-04, 08:24 PM
I guess this should be the first question to ask, when talking about ET. (I leave aside such difficult topics as defining life and intelligence, assuming we already reached an agreement on that).

So, Earth-like life forms would be largely based on oxygen and sunlight, a sharp division would be present between food-producers and food-consumers, an evolutionary process started long ago should still be very much present, and one or more species might have been passed the survival/creativity barrier, proving intelligence.

Now imagining aliens looking like less familiar but still earthly life forms (take your choice of spiders and octopuses) is less than banal. Similar problems lead to similar solutions, so I think we can assume that on Earth-like planets we'll find Earth like life forms.

How about the other non-Earth-like planets and conditions? Nobody seems to them enough tribute, although they definitely are in far greater number. Obviously, life there would answer the same adaptation request.

I propose the following exercise, starting with what we know about the other planets of our own Solar system, their satellites included, how do you thing a viable life form (or forms, you could subdivide them in simple and complex) would look like? Starting with the local conditions, what organs should it develop to get energy to survive, multiply, communicate ?

Venus for instance is quite a challenge ! To imagine organisms able to stand 90 atm pressure and 400 degr centigrades...How complex you think they would be? How would they look like? What's their evolving perspective? What is our perspective of getting a two-way communication with them? (One doesn't really need high intelligence for that, for instance by modifying bacteria's living conditions you get a change and that could be a primitive form of communication).

Another interesting subtopic would be: in what way do you think those hypothetical life forms would affect humans after contact, for better or for worse?

How about a life form capable of thriving directly in the outer Space itsefl? And I don't mean rubbing the already too exhausted "organized energy field" topic.

I'm really interested in your opinion !


2003-Sep-06, 06:50 AM
I think there might be more water worlds than ones with water and land. Perhaps we will never do better than whales, dolphins for other inteligences.

I'm not sure that very many inteligent species would neccesarily develop technology. Most creatures are naturally well adapted to their environments. We seem to be specialist at turning the lemons of our naturally poor adaptation to wild living conditions into the lemonade of technology.

Even so, technological advance does not seem inevitable past a certain point. Even human societies have had a tendency to advance technically only to a certain point then to stagnate. Slaves have been the magor labor saving devices for most of human history. Powerful trade guilds have always tried to suppress technological advances.

The invention of the printing press, the Protestant Reformation and the Roman Counter Reformation got people thinking that things didn't have to stay the way they had always been. This was soon followed by the Scientific Revolution and the gradual empowerment of the average person. Western culture became perhaps the first in human history to make a tradition of throwing off encumbering traditions. This sequence of events might be rather rare and not at all inevitable.


2003-Sep-06, 07:20 AM
Let's assume we do not become a delicacies on their menus or encounter other impediments to getting along with them, such as their wanting to take over or substantially modify our planet in unsatisfactory ways, or hunt us for amusement, etc.

If they are really a great deal more advanced, technologically speaking, I doubt if we will be able to reverse engineer their technology very rapidly. Alien astronauts probably would have only limited insight into how their technology works. Chances are that they left the technicians who really know how to build their devices from scratch back on the home planet. Besides, they might get really ticked if we tried to take apart their ride home just to satisfy our curiosity!

It is difficult to imagine them challenging our traditional way of life more than we ourselves have done or will soon do. I think we have much more to fear from bio-engineering or nanotechnology gone amuck and just the breakdown of human values.


2003-Sep-07, 01:46 AM
You don't have to go away from Earth to find living organisms that are enough to blow your mind away, or to see what some bacteriae in hostile environments might be like. Have you ever heard of "extremeophile bacteria?" (For those who haven't, they are bacteria that survive under the most hostile and amazing conditions.) All over Earth scientists have observed bacteria living in thermal vents, living off of inorganic rocks deep in the Earth, thriving in concentrated sulfuric acid, even inside nuclear reactors! There is even the bizzare case of bacteria that lived on the moon unshielded for years (no wait, that might've been a virus, which doesn't count). Our world is much more diverse then people think!
I know this answer is not exactly what you were looking for, but I think it needed to be said. Life is very likely similar no matter what kind of conditions you give it.

2003-Sep-19, 01:49 PM
Physicists have created blobs of gaseous plasma that can grow, replicate and communicate - fulfilling most of the traditional requirements for biological cells. Without inherited material they cannot be described as alive, but the researchers believe these curious spheres may offer a radical new explanation for how life beganundefined.

heres an interesting repot on how plasma life just suddenly exsists
any veiws?

life (http://www.newscientist.com/news/news.jsp?id=ns99994174)

2003-Sep-29, 05:52 PM
Rob, interesting the information about the plasma. Still, it seems there is more than one kind of plasma. The genuine kind, star stuff, it takes more than a million degrees centigrades to build it, and to my knowledge the best fusion labs in the world couldn't make it last more than a few milli-seconds.

Now there are scientists who claim that any state of matter that's gas-like but not quite is plasma. A definition is required: real plasma involves energy states so high that you can't keep your electrons orbiting their own atoms, they just fire away, and you have heavy nucleons on one hand and high energy electrons on the other.

Now life involves diversity, complexity, starting with complexity of its structure, comparing to non-living matter. You cannot have much complexity when you cannot have mere atoms, less molecules and chemical reactions.

I would be really interested to know in what way the plasma items you mention communicate?

2003-Sep-29, 05:58 PM

I absolutely agree with you on extremophile bacteria. That's what I implied, if there are bacteria capable of living in a nuclear reactor shortly after functioning, you might imagine bacteria capable of living in
Space; after all, photosynthesis itself uses as a main source of energy Solar radiation, and you can imagine that outside the atmosphere, that radiation is much more powerful

One objection though, I doubt that there are viruses in free state out there. A virus is by definition an obligatory intra-cellular parasite, it needs a cell to continue to live and multiply. The most resistant viruses are utterly destroyed after a few hours of extra-cellular exposure and for most of them it only takes less than 10 minutes.

2003-Oct-07, 09:51 PM
i believe that : the fact that humans might not be able to see (or experience ) ET forms of life, does not mean those do not exist .

2003-Oct-08, 09:17 PM
You don't have to be an expert in sociology to imagine what would be common requirements for an intelligent form of life to reach high-tech level. To promote progress and avoid anarchy you might expect them too to have a form of social organzation, with rules and ethics that would protect that form of organization and condemn anything that could break it. You might expect them to promote intelligence and life, to value acquiring of information and therefore communication. Thus, taking-over scenarios "Independence Day"- like are very improbable. To quote Arthur Clarke "...any civilization capable to reach other planets or solar systems, must have already conquer its inner demons".

Please note that I'm trying to emphasize what we might have in common. This is what's really important, we cannot but speculate on the differences.

Now even in the direst of possibilities, ("they" are refugees from a planet already destroyed by a nova or supernova of its own star), cooperation would be much more to their benefit than open conflict, even if they would have the means to wipe us out. We are born here, as an intelligent race, we might provide them with information and experience that would be very hard and long for them to obtain otherwise.

Regarding their physiology, this would necessarily be adapted to their home planet. Again, even our respective chemistries would be very different, there are, as far as we know, some mandatory conditions to be filled in order for a system to reach the level of complexity necessary to process matter and information compatible with a high degree of intelligence. And here, again as far as we know, the possibilities are rather restraint. On their home planet, you might infer that temperature must be contained within certain limits (let's say 10 to 80 degrees centigrades. Too cold and you don't have any chemical reaction to speak of. Too hot and any reaction product will dissapear, the reaction will chain with others. Now these limits, you find them exclussively on planets with an atmosphere. Liquid solutions react more readily than solid forms, and there are not many substances that stay liquid within those temperature limits: water solutions, alcohol and hydrocarbons derived from oil (which are already organic compounds).

Bio-chemistry must by definition be complex. As diversity of combinations, carbon reigns supreme. All the chemistry of life as we know it it's based on carbon. To the present date some five million compounds are known and their number increases every day. Should ET be based on carbon compounds, we can expect some welcome similarities. (Common sense tells us that since our carbon biochemistry is a highly successful one, you might very well encounter it more than once in the Universe and with greater probability in the same part of it, like the same galaxy).

Another two elements from the Periodic Table that might in certain conditions rivalize carbon are silicon and chlorine. Strange, come to think of it, that you might have living rocks or living clouds...

Since ET has to fit the definitions of life, it means it has to be capable of aquiring and processing energy (nutrition and metabolism), of processing information (nervous system and sensors for various forms of information-transporting energy, the correspondent of eyes and ears plus other possibly exotic and unknown senses); he must be able to multiply and therefore would fit into one of the two system: sexuate and asexuate. With a predominance to sexuate, since it insures a far greater diversity and therefore a better adaptability.

Other similarities would be from the domain of hard-science, if ET was able to build ships that brought him here before we got to him, his knowledge of maths-physics-chemistry and technologies based on them must be up to a certain point, coincide. You can very well expect for them to have their own version of Pythagora theorem...and of Pythagora himself :).

So, to recapitulate, ET might be carbon based, he is not idiotically-agressive, he values knowledge exchange of knowledge (communication) and thus probably promotes and protects life and intelligence wherever he finds it. He is a genius in math and physics and technology, he has a metal-based super technology.

Also, with a fair chance of being correct, we might assume that he knows a way to exceed the speed of light. Even if ET would have an illimited life span, bio-chemical processes compatible with the time-span of possible events on an atmospere planet (that need to be interpreted in due time, meaning time to interact with them) must be of a duration comparable with those on Earth. That means ET is used to process information pretty fast, and therefore he would avoid the extreme boredom of very long interstelar voyages. (True, one might use suspended animation, go to sleep to travel for great amounts of time, but changes of all kind back home during that period would become increasingly great and hard to bear and therefore, ET would have taken steps to avoid that). Now our Milky Way has a long axis of roughly 100,000 light-years. The closest stars are within a sphere with a 500 light years radius. To take round trips in a time span that would make the results of those trips worth-while one has to break that infernal light speed barrier...or to find shortcuts. Hyperdrive might not necessarily mean you have to go faster than light, it might mean you simply found a way to get access to an extra-dimension of the time-space, and therefore, you can disappear in point A of the tri-dimensional space, get in a hypothetical fourth spatial dimension and then getting back and reappear in point B without showing anywhere in between.

Another safe assumption would be a totally new propulsion system, the one ET uses. Rockets are already obsolete and dangerous and simple chemical propulsion does not allow us speeds decent enough to explore our own backyard (the Solar system) efficiently. Atomic energy is better, although governed by unacceptable risks. An intelligent race with an intelligent technologies would try to use forces already existant in the Universe, rather than try uselessly to fight them. A propulsion system that would use gravitational forces, would fit nicely enough.

The list is by no means complete, so please feel free to complete it.


2003-Oct-08, 11:51 PM
another idea, is that aliens could very well be non-detectable by humans.
they could be anorganic, or organic in a different 'level'
means= the fact that we are scanning eg. mars , but we do not recognize organised life as we preceive it, it does not mean that it doesn't exist.

it could very well be a case of ' there is more than meets the eye'

i hope i make some sense

2003-Oct-09, 10:05 AM
You do, but what would we look for? If we're not looking for carbon based, oxygen breathing organisms, then what are we looking for? We can predict what we may find, but until we do we really do have no idea what we are looking for.

2003-Oct-09, 08:12 PM
Originally posted by matthew@Oct 9 2003, 10:05 AM
We can predict what we may find, but until we do we really do have no idea what we are looking for.
exactly, we also need to understand that we may find only what we expect, meaning there may be something other living there, on a different level

our technology and our cultural back up sometimes limits our horizon.
we can't be sure if alien life exists, when we are only able to detect life when it fills our -could be limited- range of knowledge. Nanotechnology is a good example, could alien life exist in a nano environment? or on a non human dimention?

we do not know much, thats my whole point

2003-Oct-10, 06:22 PM
Some have proposed the idea of life in the atmosphere of Jupiter, that would look much like stingrays. Under the glaciers of Europa there might be life. Speaking of the Jupiter system, when I was like 11 or something, I read a sci-fi comic book called "Allan Kämpe" (the name of the hero), and this was made back in the late 40's-early 50's I believe. This was truly before its time. Anyway, one of the adventures was based on some new amazing spaceship in which our hero and two others went all the way to Jupiter, took a dive in the clouds and then went to Callisto, one of the moons. There, they found a dead civilization that gone under when their sun (Jupiter!) died out. Very fascinating story.
Maybe there can be simple life forms even on Titan. Simple single cell life forms in that case. Now Venus may be too hot at least on the surface, but what about life in the atmosphere?
Now, more complex and even intelligent life forms in other solar systems could very well be somewhat similar to us, but they could as well be completely different in every way. Their morals could be absolutely different for example. Anyway, it depends entirely on what their environment had to offer from the beginning on how they will evolve. Life forms that can exist in outer space, or even evolved there is an intriguing thought... not sure how it would happen.

2003-Oct-11, 08:06 AM
Much about life we assume from data we have collected on Earth, from animals on Earth. We don't know what form intelligent life will take, or what their social structure may be like.

Life has probably adapted to various situations in ways we never thought of.

2003-Oct-11, 08:39 AM
Originally posted by matthew@Oct 11 2003, 08:06 AM
Life has probably adapted to various situations in ways we never thought of.
absolutely ;)

Basically we have absolutely no idea what to look for when searching for alien forms of life.
Life can be anything, being ignorant our 'cutting edge' technology space machines might be very well surpassing alien forms of life in other planets, just because the do not fit human preceived data, which is really for laughs.
Our idea of 'no life in Mars' is so poor in evidence, just because man could not survive Mars environment, nobody else does.
Or - just because our equipement cannot detect life in Mars, there is absolutely nothing there, how naive. How egocentric :rolleyes:

We are still in middle ages, thinking of our tiny little earth as the absolute center of all life in cosmos.
Our egocentric view of the universe is making us blind when we expect alien life to follow -even remotely- our earth patterns/data/technology/physiology etc.