females. I think its because of girls being easier grow inside a woman and the viability of egg and sperm quality. Everyone actually starts out as girls in utero.
actual figures, e.g. given by @johnpowell, show that men now outnumber women (quite unlike 1950, when women outnumbered men (BTW, I should have said in the above post, these figures are 000’s). That could not be good, could it?