You are correct that we are nowhere near that in life support technology, however, there don't seem to be an fundamental hurdles there. If we end up opting for

You are correct that we are nowhere near that in life support technology, however, there don't seem to be an fundamental hurdles there. If we end up opting for a biological life support system, adaptation would not even enter the equation - it'd be a matter of genetic engineering. An obvious danger would always be onboard ecosystem collapse, of course.