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Alien Convergent Evolution Probable or Improbable?

Aliens could be humanoid even able to speak English.
0 (0%)
Aliens could be humanoid to a limited extent.
0 (0%)
Aliens could have water basis and or neurones in common but that's all.
1 (33.3%)
Aliens are probably very different in every way.
2 (66.7%)
There are no alien life forms.
0 (0%)
There is something mysterious in the nature of the universe that gives irrational outcomes.
0 (0%)
Life as we know it is the work of highly intelligent aliens.
0 (0%)

Total Members Voted: 2

Voting closed: 02/04/2014 15:10:05

Author Topic: Extraterrestrial life, non water, non DNA, non neuronal?  (Read 2342 times)

Offline Europan Ocean

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Good day, I think life on other worlds, thinking rationally, may not be water based, nor have DNA nor have nerve cells, and may not be animal or plant. Yet could be intelligent, like a lizard or more.

Other worlds have large amounts of water or ammonia, nitrogen, bromine, oxygen, chlorine, CO2...

It may be that the gravity of a small gas giant on the rock is reduced by the mass of gas above enabling a high pressure life form to move, to fly...

I have a friend who matriculated to study and graduate from a medical degree. In his first years there at UNSW I debated that rationally thinking, a sci fi humanoid alien, coming to Earth with so much in common with us that it could talk and speak English, and prove to have 46 chromosomes and reproduce with us was extremely extremely unlikely to the point of impossible! He disagreed.

I remember him talking in high school about jumping on the moon and never falling down, which disappointed me, since the moon has gravity. He should have known.

If we look at Earthly convergent evolution, there are snails, and sea snails, and they look so similar! There are flying fish and birds. Eels and snakes. But nothing like humanoid fish, even after billions of years.

I look at Dolphins, and we have common ancestors, we converged in evolution a speak languages, but they are so different! The Dolphin brain is large and powerful but so different.

How could there be such a thing in all the cosmos, as a real humanoid? Even if water based, with DNA and and neurones, why would it have four limbs and not be more like an Octopus, or an eel... like it it's evolution it was Octopusoid instead of fishoid and then developed land features, like our frogs...? Exotic alike Hawking's idea?

They could respire bromine gas, and a craft would be dangerous to enter. Bromine gas 2000 kp...

Do you think humanoids are rationally impossible?

Otherwise how could there be the same kind of creatures by chance?
« Last Edit: 26/02/2013 14:34:10 by Europan Ocean »


 

Offline cheryl j

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Re: Extraterrestrial life, non water, non DNA, non neuronal?
« Reply #1 on: 27/02/2013 16:12:23 »
If there is life else where, it is not beyond chance that like life on earth it would be carbon based. Carbon is, in the words of one entertaining chemistry professor I had, the **** of the periodic table. It likes to combine with other elements, especially other carbon atoms, forming long complex biologically active molecules. And there is lots of carbon out there in the universe, which makes it a likely candidate.

I'm not sure what you mean by "neurones." Nervous systems are in some respects extensions of sensory systems. Sensory systems help organisms respond to external changes, find energy sources. Even primitive single cell organisms can move towards concentrations of nutrients and away from lower concentrations, a rudimentary form of "taste" or "smell." Some primitive organisms respond to light, a very simplified form of vision. A nervous system or brain allows better perception and response to more complex stimuli in the world. If that is an evolutionary advantage on earth, it could be an evolutionary advantage on other planets or moons as well.
 

Offline Europan Ocean

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Re: Extraterrestrial life, non water, non DNA, non neuronal?
« Reply #2 on: 28/02/2013 04:53:49 »
Thanks Cheryl, yes I did mean the same kind of nervous system we have, by neurones, at the base level. Neurones, the specialized cells that make up the nervous system.

Carbon chem is very important, I agree.

 

Offline CliffordK

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Re: Extraterrestrial life, non water, non DNA, non neuronal?
« Reply #3 on: 03/03/2013 11:56:41 »
Hominids are very specific to Earth, so it would be difficult to call an alien a hominid.

There may be animals on Earth that have an intelligence beyond what we give them credit for.  However, one of the things that Humans have is extensive tool building which requires some kind of manipulator, be it with 5 fingers on a hand, 4, or 6?

Likely some kind of hair, fur, or feathers would be found on an alien planet, but nature's solutions to problems presented to it could be vastly different.
 

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Re: Extraterrestrial life, non water, non DNA, non neuronal?
« Reply #3 on: 03/03/2013 11:56:41 »

 

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