• Quick note - the problem with Youtube videos not embedding on the forum appears to have been fixed, thanks to ZiprHead. If you do still see problems let me know.

exobiology

bewareofdogmas said:
What about starfish, slugs and worms?
I thought about those (and 6 limbed insects), but it's my natural 4 limbed chauvinism showing through. I'm thinking that dominant life that can travel from place to place and manipulate it's environment has to be of a certain size. There are some "size" constants in the universe, like the critical mass of uranium, so creatures big enough to do something like pick that up and move it around should have an advantage. And I think all large creatures on earth are the 4 limbed type (which makes me wonder why now).

It's just a thought exercise, but don't think it's worthless to wonder about it like some have said. It makes us ask why we are the way we are and why.

Like why do so many creatures keep their most important organ, the brain, hanging on an appendage on top of their bodies and not encased inside their torsos? The power of having useful sensory organs like eyes hanging out there and right next to the brain must be more advantageous than hiding the brain away. So would some kind of "head" be a common life form trait?
 
We have four limbs because the fish we evolved from.
heads keep the brain near the eyes and ears; that cuts down on the nerve impulse lag time.
 
bewareofdogmas said:
The surface of stars?!!:roll: You need to learn a lot more about stars.

rember lives it the taking in of energy for the perposes of you own reproduction. Plasma cells acn cetianly do the second part. So what if the rempretures on the surface of stars are about 20000C all that means is that convential (ie molicule based) life can't exist there. If you belive some of the stranger theories that physicists have come up with about dark matter you could have life in the center of stars.
 
Ok then. Please define life for the perpouses of this dicussion. With out such a deffinition we can get no where (and yes I know under the difintion I was using worker ants are not alaive). To a large degree we run into the problem that we are stuck with an earth defintion of life so that is always going to limit us on this question.
 
Dark matter doesn't interact with normal (baryonic) matter except through gravity, so any dark matter life form would be undetectable by us and therefore is irrelavent to this discussion.

Furthermore any sort of life would require controlled chemical reactions which are impossible on the surface of almost any star - the coolest stable stellar objects have surface temperatures of ~1300K, which is far too high for anything but the most basic molecules to survive, and certainly no lifeform.
 
wollery said:
.

Furthermore any sort of life would require controlled chemical reactions

No this satement is only true for every type of life we have encounterded and all thoes we can think of. (I just know some sci-fi fan is going to object to the second part of that statement)
 
If we are talking about an advanced alien civilization, we should take a look at what a civilization needs.

Technology means use of tools. Tools mean use of fire.

For tools, we need materials - rock or organic material. And we need a place where this can be stored, so purely airborne life forms could be ruled out, I think.

For fire, we need oxygen and combustible materials, which rules out aquatic life forms and ammonia-based atmospheres.

We also need a primary star quite like our sun, that gives off the right kind of radiation for a very long time - several billions of years. The planet must be in the right distance, neither too close nor too far.

In short, a world with an alien civilization would be very much like Earth, so I would not be surprised if its life forms are very much like ours.
 
Chaos said:

For fire, we need oxygen and combustible materials, which rules out aquatic life forms and ammonia-based atmospheres.
It might be posible to use eletricity in place of fire (great now I'm thinking of a massive eletrick eel type thing). Also you don't need oxygen for fire (spay wire wool with flourine if you don't belive me).
 

Back
Top Bottom