You're studd...studd...studd...studdering, Taz.
Hey,Lyston.
Look up sexual evolution. It is explained quite well.
The problem you seem to be having is the usual creationist thinking that these major leaps are made all at once in one replication. They are not.
Look at snails as a living transitional. Both male and female in the one organism. Pay particular attention to
Helix aspersa. With understanding of the mechanisms involved in evolution and with a respect for the time spans involved you should have no problem answering your own question.
Note I did not say you would have to believe, but at least you would know the answer from an evolutionary perspective.
This male/female thing is an old creationist argument, btw, that has been torn to shreds decades ago. Its called a PRATT (problems refuted a thousand times). If you really want to do battle with evolution I suggest you research the knowledge-base prior to forming an argument. Know thine enemy, as it were.
Welcome to EvC.