Re: Alien, I mean really Alien.
 

<font size="2" face="sans-serif, arial, verdana">It's actually a bit different than that... http://forum.shrapnelgames.com/images/icons/tongue.gif

In reference to animals, there are actually 34 basic forms "phyla" currently classified. Although they've developed at different times in history, I don't believe any have gone extinct. Mostly they've just gotten more complex (but not always sort of)! http://forum.shrapnelgames.com/images/icons/tongue.gif

From an evolutionary and multicellular viewpoint, things have progressed like this:

Sponges "Porifera" - No tissues; like a colony of single-celled organisms

Jellyfish, Corals "Cnidaria" - True Tissues (two); radial symmetry; partial digestive cavity; nerve net

Flatforms "Platyhelminthes" - no body cavity; bilateral symmetry; full digestive cavity; 3 tissues; head ganglia (nerve center)

Rotifers "Rotifera" / Roundworms "Nematoda" - pseudocoelom (sort of have a body cavity); 3 tissues; have "butts" and mouths http://forum.shrapnelgames.com/images/icons/tongue.gif ; head ganglia with primitive nerve cord

Segmented Worms "Annelida" - body cavities; 3 tissues; exoskeleton; circulatory and digestive system; head ganglia, simple nerve cord

Insects, Crustaceans "Artropoda" - body cavities; 3 tissues; exoskeleton; circulatory, digestive, and respiratory systems; head ganglia, increased nerve network

Octopus, Snails "Mollusca" - body cavities; 3 tissues; exoskeleton; circulatory, digestive, and respiratory (gills, lungs) systems; brain; nerve network

Sea Stars, Urchins "Echinodermata" - bilateral symmetry (but radial adults!), 3 tissues, body cavity, endoskeleton, no circulatory or excretion system, no brain, nerve network in skin

Vertebrates (Us!) "Chrodata" - 3 tissues; bilateral symmetry; developed digestive, circulatory, respiratory systems; developed brain; nerve cord; endoskelton

I'd imagine alien life given similar conditions as Earth (O2 + water) would progress in a similar fashion. I don't think its nearly as random as you'd think. If you want to have complex organs like eyes and ears, you're going to require some sort of sophisticated nerve system and brain to process and interpret that info. Big brains require lots of energy, so you'll need to be mobile and have sophisticated respiratory, circulatory, and digestive/excretion systems for that to be possible, and so on.

Of course, other factors like the planet's gravity or surface conditions may dictate physical appearance or types of sensory organs (i.e. sonar, electromagnetic, etc), but the internal mechanisms would be probably be quite similar. After all, evolution is just a process of selection - and given the same sort of conditions you'd expect given enough time, to see the same end results.

<font size="2" face="sans-serif, arial, verdana">I think your end conclusion is a little far-fetched, but your general idea holds true on a smaller scale, i.e., Dinosaurs vs. Mammals sort of scale. If the Dinosaurs had been able to hang around longer, then perhaps we'd be more of a Reptillian-humanoid...however, we'd still have the same body systems and macroorgans that we do now. It's just a good setup for evolutionary success. http://forum.shrapnelgames.com/images/icons/tongue.gif

Now, talking about other types of planets and possible life or intelligent Alien behaviour - that's just another serious can of worms.

[ March 25, 2004, 19:43: Message edited by: Captain Kwok ]

Re: Alien, I mean really Alien.
 

<font size="2" face="sans-serif, arial, verdana">My point is that we assume dolphins aren't sentient because we have thousands of years of history defining them as 'dumb animals'. SUppose dolphins didn't exist on Earth, but on planet Blarg. Now suppose we sent a spaceship to Blarg and discovered the dolphins, frolicking and singing to each other. WOuold we say "they're just a bunch of clever but sub-sentient animls" or would we start with the assumption that they might be sentient and work our way up? And if we did the latter, what would we find?

I guess what I'm saying is, we take the various life forms we already have for granted. If we were to look at them with fresh eyes we might be surprised.

But I can't remember what this has to do with xenodiversity. someone remember to ask me when I sober up.

Re: Alien, I mean really Alien.
 

<font size="2" face="sans-serif, arial, verdana">My point is that we assume dolphins aren't sentient because we have thousands of years of history defining them as 'dumb animals'. SUppose dolphins didn't exist on Earth, but on planet Blarg. Now suppose we sent a spaceship to Blarg and discovered the dolphins, frolicking and singing to each other. WOuold we say "they're just a bunch of clever but sub-sentient animls" or would we start with the assumption that they might be sentient and work our way up? And if we did the latter, what would we find?

I guess what I'm saying is, we take the various life forms we already have for granted. If we were to look at them with fresh eyes we might be surprised.

But I can't remember what this has to do with xenodiversity. someone remember to ask me when I sober up. </font><hr /></blockquote><font size="2" face="sans-serif, arial, verdana">Sounds like what happened in "So Long and Thanks for all the Fish"

Slick.

[ March 25, 2004, 20:39: Message edited by: Slick ]

Re: Alien, I mean really Alien.
 

<font size="2" face="sans-serif, arial, verdana">Well, if it serves the same purpose as fear, and it provokes the same response as fear... why don't we just call it fear? There will undoubtedly be biological differences but the end result is the same. After all, how do i know that when *you* feel fear you feel the same thing as me? How do I know you don't see red as what I would call call blue?

It's like the Turing test for AI: You can't know for sure whether a machine is actually intelligent or just doing a really good impression of one that is, but when it gets to that stage there's very little point trying to tell the difference anyway. </font><hr /></blockquote><font size="2" face="sans-serif, arial, verdana">What you seem to be saying is that 'you can't know how other beings think, so they might be thinking differently'. I'm saying, if stimuli and responce can be made to match up, then why should they be different?

I'm also saying that any different stimuli and responce can be simulated with the human brain.

Re: Alien, I mean really Alien.
 

<font size="2" face="sans-serif, arial, verdana">My point is that we assume dolphins aren't sentient because we have thousands of years of history defining them as 'dumb animals'. SUppose dolphins didn't exist on Earth, but on planet Blarg. Now suppose we sent a spaceship to Blarg and discovered the dolphins, frolicking and singing to each other. WOuold we say "they're just a bunch of clever but sub-sentient animls" or would we start with the assumption that they might be sentient and work our way up? And if we did the latter, what would we find?

I guess what I'm saying is, we take the various life forms we already have for granted. If we were to look at them with fresh eyes we might be surprised.

But I can't remember what this has to do with xenodiversity. someone remember to ask me when I sober up. </font><hr /></blockquote><font size="2" face="sans-serif, arial, verdana">Ok. http://forum.shrapnelgames.com/images/icons/icon7.gif I'll also ask what the disagreement with what I was trying to say was, because I entirely agree with you on this. In fact, the humans that assert that animals (from dolphins to rats) are "not intelligent" or "sub-sentient" are either just plain wrong, or are framing their questions in ways that I think are rather off.

PvK

Re: Alien, I mean really Alien.
 

hmm, I seemdd to have generated some replies. If only I could rememebr what the hell I was talking about. But, to reply to everyone at once: Yes/no/thanks/of course/sorry/curses!/oops (delete as appropriate)

Re: Alien, I mean really Alien.
 

There are no aliens living on other worlds. It is mathamatically improbable that sentient space faring life could have evolved on another world given the absolute uniqueness that spawned life here. The chances for another life giving planet are so astronomically rare that if you could explore space in its entirety in one day it would take you a trillion years to find one planet like Earth. We are it and until one lands on this planet and proves me wrong, I am going to stick by this narrow minded concept.

Re: Alien, I mean really Alien.
 

Atrocities:

I'll give you the chance that Aliens visiting us here is next to nothing, but I sincerely doubt your assertion that there is no alien life elsewhere in our galaxy. Once we have better tools in place, we'll start identifying planets much more like our own than the ones they've found so far.

Re: Alien, I mean really Alien.
 

CK I have to tell you that our being here is an accident of epic proportions. The simple fact that life evolved on Earth is such a rare event that chances of it occuring twice or more in the universe is so great that if you took the number 1 and put 0 behind it to the point that it could circle the universe a centrillion times to the billionth power you might be within 1% of the chance.

This planet is so rare that it equals 1 10th of a grain of sand compared to the entire galaxy. And we are wasting it away.

No CK, life does not exsist "out there" it only exsists here.

Re: Alien, I mean really Alien.
 

Wow, did this thread take off. I bow to Captain Kwok and others superior knowledge, as I explained I am no expert I was simply trying to put forth some limited knowledge I had. So my numbers might be wrong but I seemed to remember it was a proportion such as 5 out of 20. It could well be 3 out of 15, but I'm pretty sure the number of fossils was less than 20 "types". The types I was referring to are (using my simple example)
1. creature with a backbone and 4 limbs.
2. creature without a backbone.
3. Creature with a backbone but 3 unsymetrical limbs spaced around torse (like Cygnans from Jupiter theft).
4. Creature with 20 legs and backbone (sort of like a centipede but not an insect).
5. creature with a tubular body and circular mouth studded by teeth in 3 sets (like a lamprey).
6-20 various other types.
basically think of 20 really alien variations on possible forms, but only (in my example) 5 survived.

I read this in a magazine many years ago and it stuck in my mind. The magazine could have been Popular Science, National Geographic or Time for all I know. I apologise for being unable to provide links or detailed information, really I was hoping for someone with more knowledge to elaborate on what I knew. For the person who wanted to know the 3 types of Monotremes, they are 1 type of Platypus and there are 2 type of Echidnas.