The various threads about whether this or that environment can support life, etc. got me thinking...
Why do we assume aliens will be at all like us?
I don't mean in the low-budget sci-fi "actor in a prosthetic forhead" kind of way.
I mean realistically.
There often seems to be an assumption that life will be more-or-less earthlike. The morphology may be different, but the overall chemistry will be the same. Or the chemistry will be different, but the overall energy budget will be the same. Or the overall energy budget will be different, but the general mentation processes will be the same. Or the mentation processes will be different--but not too different--but the lifespan will be more or less the same (+/- a couple hundred earth-years).
It seems to me that given the scope of the universe, it's just as likely that alien life will be totally inscrutable to us, and we to it, as that it will be anything we could possibly hope to communicate with.
I dunno. A low-energy environment might have some kind of living ooze, that migrates across the surface of a frozen moon at a glacial pace, and thinks even slower, using interactions between itself and the radiation from the gas giant it orbits to generate its thought patters. Would we even recognize such a thing as life? Would it even recognize us?
Or what about a sentient gas cloud, spanning hundreds of light-years deep in the searing radiation hell of a galactic core, with a lifespan measured in aeons. Would it even notice us? Or we it?
For all we know, the galaxy could have plenty of life, but all orthogonal to us, not just in time and space, but in terms of its very nature.
What do you think?