Humanoid Aliens

I brought this point up in another post here:

http://www.able2know.com/forums/viewtopic.php?t=30439

My main point is that there are too many circumstances that make Earth unique; every factor of our planet's evolution has too much chance.

Just the basic makeup of our Earth, from its 23 degree tilt that causes seasons, to the exact size and placement of the Moon that causes tides and stablizes Earth's orbit, to the comet that hit the Yucatan peninsula 63 million years ago; these seem to be unique event piled on unique event that would cause other deviations if not followed exactly.

May other similar planets have intelligent carbon-based vertabrates? Maybe. Would any look like us? Very doubtful...

i disagree i think there would be alot of aliens with 2 arms, 2 legs, a head, a torso, 2 eyes

of course your gonna say no to humanoid aliens you say no to aliens in general

Seems we are going back and forth on the same topic elsewhere.
My take for this thread is that the number of habitable planets that create a dominant intelligent life form able to travel into space just in our known universe is likely (although as of yet unproven) to be anywhere from 250,000 (a very low estimate) to over 2 million. Going with the low ball estimate I find it hard to picture 250,000 other evolutionary paths without at least one other evolutionary path bringing forth humanoid, or even human byproducts. So to admit that it is possible that our species may have evolved on at least one other planet in our known universe the question is not so much are there other planets with humans or humanoid on them but the real question at hand is how many planets does it take to produce a human or humanoid species. Is it one in 10,000? Is it one in 50,000? Is it one in 500,000? Only having our planet and it's species as a vantage point and not knowing how many habitable planets are out there make all this nothing more than pure speculation.

did you say you believe 1/3 of galactic dominant species will be humanoid?

naw if i had to guestimate i would say 1/50, i dont beleive that humanoids could be THAT common

That's my estimate. The sad thing is that we have the power to find out. We could all work together, throw away all prejudices and bigotries and provide for an uninterrupted chain of evolution that places our human species well into the stars before our sun goes Nova. It is so unlikely that we poses the strength as a species to overcome our own diversity that it is unlikely that we will be here in 5000 years let alone 5 billion, but that does not mean that it is not possible if we wanted to make it happen. (but I suppose this would be a topic for a different thread)

how did you come up with the estimate, it seems too much

Yeah, you are probably right. 1/3 to 1/2 does seem a bit high.

OK, lets say about 1/9 to 1/7 of the habitable planets produce primatelike to humanlike evolutionary chains.

This is a made up number. The fraction itself has no value. The thought process that lets you accept that there could be at least 1 other planet that permitted humans to evolve is the goal at hand. Regardless of the percentage of habitable planets that could support human life. to accept the likely hood that it could happen on at least 1 other planet then changes the question

Then the question becomes 1 out of every how many habitable planets will create a human evoltionary chain?

who knows, just as long as there are intelligent humanoid aliens out there, im cool

superhuman humanoid aliens would be awesome