Zero G Space Settlement

Hi,

I wonder what kind of physical and brain adaptations would be need for
people to live directly in 3-d space cities without gravity.

Yes. I know normal, standard, current human beings can't stand zero g
for too long. But in the long term -I really mean long term- is there
any reason why human biology could not evolve (nature, artificially)
to beings that are able to live in zero g without consecuences?

Just for curiosity.

Regards,

Omar Vega