So I did some more digging. In the room at the end where the astronaut is at first seeing himself as a old geezer and then takes the form of his geezer self, he is at the final challenge of his life which is to face his own death. He has a glass of wine and drops the glass. The glass is apparently meant to symbolise his physical body and the wine his spirit. (I would have so never gotten that wine part on my own.) Anyway the glass is broken but the wine is still there so you do the math between the two.

In the end the monolith tells him that man's evolution is so dependent on our technology that it almost replaced us and it tried to destroy us and in the end what are we left with? The light never dies. And thus the star child is born...the next stage in the evolution of man.
So from ape, to man, to star child? Does this mean the final stage of our evolution is to become like the aliens who made the monoliths?
Oh and I think all the lights were a star gate of sorts but don't quote me on this one.