Questions about genders ... male/female

[Reader]

Reader, this represents the most common misunderstanding of evolution that comes from theists. (Not saying you are a theist, just saying that they bring this up too often.)

Evolution does not necessitate that everything trend towards infinity. What I mean by this is that if an organism is perfectly suited to it's environment, then we wouldn't expect any genetic drift. Obviously no organism is perfectly suited to its environment, so there is always space to improve in some areas. However, if a certain aspect of anatomy or physiology functions very well, then there is very little selection pressure. So even if a new gender were to have mutated, it would have very likely been ousted very quickly, as the likelihood that a single new gender would be able to reproduce would be pretty low. In fact, two new genders would likely have had to mutate pretty early in the evolutionary process at the same time within the same population in order for them to have been sexually selected.

Two genders is all that is needed. And if things had gone differently very early on, I might be saying "six genders is all that is needed."

Thank you! Yes, this is the answer I was looking for! Thanks for clarifying it in layman's terms. A couple of more questions if you don't mind ... I asked this above in another post, but will ask here again a different way. So, if we started off as one "sex" ... how did we get to two sexes? How many of the one "sex" did we have until we evolved into another to be able to reproduce? Would the first "sex" have died off before more could be "made"? Does that makes sense? Trying to think this through before we talk about it in class.