Re: Are we alone in the universe? Maybe so.........
A Lone Voice wrote:With all the billions of stars in our galaxy, and the billions of galaxies in the universe, it seems probable that there is other, intelligent, forms of life 'out there.' But how many might even come close to resembling us?
Without a moon, placed EXACTLY where it is
With the type of sun we have
a variance of temperature like Earth
possibly possess the same 23% tilt
presence of seasons, allowing life to evolve
similar sort of land mass, and plate tectonics
ocean currents to regulate weather,
temperature variance (of what, 120 degrees?)
a comet had not hit the Yucatan peninsula 63 million years ago, changing the Earth from an environment favoring reptiles and dinosaurs to one favoring mammals?
I submit that it is possible if not probably that in order to obtain a remotely similar evolutionary path we do not need to so exactly duplicate our planet as much as duplicating very similar conditions. Had a meteor not wiped out the dinosaurs we may have still eventually evolved into what we are now. Since our solar systems 9 planets have moons it is likely that many planets in our known universe have a moon but having a bigger or smaller moon or two moons would not negate the possibility that we would still have evolved as we are. I agree that the more similarities between two planets the more likelihood of there being a similar evolutionary path but I don't see it in my head as to why it is not just as likely to assume that humanoid based evolution may not be the norm and not the exceptions.
Lets pick a rough number of the 70 septillion stars in the known universe that there are 250,000 planets very similar to earth out of the possible 1 million that support habitable life. Taking out of your question (and I do apologize if it was important to the point) the requirement that this has to be now and not 500,000 years ago or 2 million years from now, I would submit that most habitable planets would produce a dominant intelligent species able to harness electricity, build magnificent structures, machines, and vehicles. etc. etc. and control the destiny of all other living creatures on each of their planets.
So if most habitable planets produce an intelligent dominant species it is not unlikely to assume they would walk upright, have 2 arms, 2 eyes, 2 ears etc. That may make them humanoid in a vague sense of the word but I think you were looking for aliens that could mate with a human from this planet and produce a human offspring. So of 250,000 possible planets that may be like Earth if we became dominant and we are what we are then I don't see why it is so far fetched to assume that most of those planets would not produce beings very similar to ourselves.
I submit that we evolved into what we are because we obtained early in our evolutionary process the ability to become dexterous with our hands. Having opposable thumbs and being able to grasp a stick or a bone and hold it both parallel and perpendicular to our forearm allowed us to use this as a tool. Using tools was the catalyst that sparked our path towards intelligence. The more we used tools the more we evolved and began to create better tools and then began to use language and as we used language our intelligence grew even faster. There is no reason in my mind not to assume that on any habitable planet during the course of each species evolution there would not be a creature who started using tools and developed language and evolved into the dominant intelligent species. How many of those were primates, I can't fathom but my instinct leads me to believe that more of them were primates then were not .