When you put things into terms of individuals, you will never understand evolution. Evolution works in terms of populations of breeding or otherwise reproducing individuals.
You are asking the chicken egg question.
When you look at comparative anatomy from single cells to man, you can follow the developments. Remember, we still have single cells and that things don't necessarily disappear. There is no direction to evolution from simple to complex as my first sentence in this paragraph may suggest.
Evolution is an elegant Theory. To understand it, it takes systemic thinking and open minded powers of observation. This is how Darwin came to it.
I think the chicken/egg question is valid.
To believe their system, an evolutionist must have every bit as much faith as the creationist does in his, I think.
I'm really not here to try to convince anyone anything, but it is a fun debate.