It is well known that the spirits of men who lived a good life go on to live in the star that God made for them, but if a man does not live a good life, his spirit will be reincarnated as a woman (42c) -- but it is less well known that spirits persisting in not living the good life (i.e., not understanding the geometry behind the motions of the stars), but instead are stupid enough to trust their senses, will come back as birds (91e):
"As for birds... they descended from innocent but simple minded men, men who studied the heavenly bodies but in their naivete believed that the most reliable proofs concerning them cold be based upon visual observation."
So I guess that is our future.