Predicting what alien ecospheres are like…

[ElectricFetus]

On this post: The natural history of the future(predicting evolution) it came to me that it might be even more intresting to predict what alien life is like rather then what Earths future is like (at least that way its a lot less likely your wrong)

So what would life be like...

... at half our gravity?

... at double our gravity?

... on a cloud world (like Jupiter or Venus)?

... breathing Sulfur, Hydrogen or Halogens?

.... without any water (some other fluid?) ?

... in Europa, how about on Titan?

... on a moon of a bigger planet?

... in a star system with more then one star?

... without a moon? (And if you have read the book “what if there was no moon” then your cheating!)

... without day and night?

... in interstellar space (natural intersellar life?) ?

 

[gurglingmonkey]

Well, on a smaller planet the creatures wouldn't need very thick bones, so would probably be tall and spindly. And because the planet wouldn't have as much gravity as ours they would need to be able to breathe in a thinner atmosphere. Would bigger lungs work in that case? I'm not sure. And what would happen to oceans, water, and what have you in a lower gravity enviroment?

Gurglo

 

[Dr Lou Natic]

This is tough really. Predicting future evolutions on earth is easier because you have base animals to work with and you can imagine what type of weather changes could occur, you have a history to look at.
With this I'm not sure. I can only think of very general things like small planets might allow for giant heavy animals and stuff like that.

I know we have no examples to work off of but I assume all life would start out as plankton like organisms. And who knows? Perhaps Ho2 and Co2 are required and nothing else in the universe allows for life.
Because as far as I know, life is the product of the sun shining on still water. That life "feeds" on Co2. We call it plankton. What plankton is, is really millions of different organisms. Kind of half plant half animal. I believe all plants and animals came from different types of plankton. Because the wierd thing about plankton is they are all apparently the same but each little one is different. Some are little blobs, some look like strange little crustaceans etc etc. Maybe some blobs evolved into plants and maybe different crustaceans evolved into different phylums of animals, whatever.(I think "phylums" are the categorical thingy I'm thinking of, I don't know)
The point is I'm only willing to discuss life that evolved from similar conditions to those that life on earth did. Correct me if I'm wrong but we have no reason to think life could evolve under any other conditions.
Still, there would have to be at least millions of planets in the known universe with Carbon atmospheres and water.
But if plankton is a natural process under these conditions than I think it probably starts out almost exactly the same in every instance. "Alien planktons" are probably all over the universe and probably are very similar to earth ones.
Maybe primitive organisms like jellyfish are common also. Its when you start talking birds and mammals that it gets messy. I think they only started up because of "freak" atmospherical and ecological changes.
But then, I wouldn't be surprised if they found a life harbouring planet that had the exact same categories as we do (reptiles, birds, fish, mammals, crustaceans etc etc etc) because that might just be how it naturally happens.
Ofcourse I would be more than surprised if there were red bellied black snakes and thompsens gazelles. That seems like an impossibilty.
But legless reptiles and horned, hooved mammals? Maybe.

Its hard to say, I tell you what I would be alot more interested if we found a life harbouring planet with a fully functioning eco-sytem complete with a diverse animal kingdom than if a technologically advanced alien species found us.

 

[sargentlard]

Originally posted by WellCookedFetus


So what would life be like...

... at half our gravity? could be very tall and wide creatures

They wouldn't have strong bones then methinks. Just strong muscles

... at double our gravity?

The flying ones would be quite strong and long...aerodynamic

They might be heavy strong muscled like creatures with thick bones

... on a cloud world (like Jupiter or Venus)?

Obviously they would be resistant to acid. Not very reliant on sun so probably warm blooded and possible anerobic.

... breathing Sulfur, Hydrogen or Halogens?

Anarobic and their metabolism might involve bacterial breakdown of these chemicals.

.... without any water (some other fluid?) ?

Anarobic then probably. Depends on the fluid as to are they strong boned or just muscle

... in Europa, how about on Titan?

Obviously thick skinned to survive the harsh climates. At Titan; i'd probably suspect nothing more than bacteria.

... on a moon of a bigger planet?

depends on the Moon's atmosphere, the planet's effect on the moon

... in a star system with more then one star?

Also depends on the star system and the workings on the two stars in conjunction....too vague to take a guess here.

... without a moon? (And if you have read the book “what if there was no moon” then your cheating!)

Don't really know how the moon effects animals

... without day and night?

Without day AND night? Then are in a constant state of suspension in a timeless vaccume????


... in interstellar space (natural intersellar life?) ?

Depends on where they are???

 

[spuriousmonkey]

Originally posted by WellCookedFetus


... without a moon? (And if you have read the book “what if there was no moon” then your cheating!)

I haven't read it, but I think that there is a common concensus that the moon actually accelerated evolution, by creating a special dynamic environment dependent on tides.

 

[ElectricFetus]

well form the book earth would have ended up like venus, so be happy the moon is there!

Without day AND night? Then are in a constant state of suspension in a timeless vaccume????

you know what I mean you butt @#$%er! "or" "and" up yours typo mentioning is taboo here!

 

[NenarTronian]

I'd like to just say that most life in the universe probably relies on water, and life as we know it is based on water, but does that mean water may not be water based? Or even carbon-based for that matter...i'm not well versed in biochem or organic chem but i'm sure some people on here are so... COULD life happen with out water? how about without carbon?

 

[spuriousmonkey]

Originally posted by WellCookedFetus
well form the book earth would have ended up like venus, so be happy the moon is there!!

let's go anal retentive and state that I thought what effect it would have on life. Not if there would be life or not.

 

[sargentlard]

Predicting Aliens this way is a terrible way to go at it. I am sure WCF knows that the conditions he listed are Vague...it's just for fun so let's keep it that way.

 

[eburacum45]

Well, here are some of our aliens (humanoid aliens are forbidden in our imaginary universe, just as they probably are in the real one)
Lignosagittae- europan-like moon underwater chemotrophs
Cthonids-Earth like atmosphere, low gravity, live underground like moles to avoid flying predators
Dyglufsare-Earth-like atmosphere, large tidal range- tidal mudflat species
Hildemars Knots-artificial relict species living on neutron star surfaces
Muuh-Cold temperature moon species based on liquid hydrocarbons, fullerenes, ammonia and nitrogen.
To'uls-Hot temperature high CO2 environment species
Rheolithoids-silicon based high temperature magma dwellers
and others-
anybody who has a species (or anything else) to contribute is welcome
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