How could evolution have produced male and female?
The first life would have had to be asexual, such as bacteria are today, as most biologists will admit. How did it split into male and female? If it somehow formed a male, it would also have to form a female at the same time in order to produce progeny. That means there would have to be at least 2 seriously significant mutations producing 2 completely different results which allowed the previously self-replicating life to suddenly require each other in order to replicate. And the mutations would be very complex in nature even at a basic level, for there must be compatible mechanics to combine genetic material in addition to having "male" and "female" genes which combine (egg and sperm, or the equivalent). Moreover, both of these mutations would have to exist at the same time, in close proximity to each other (can't mate if they are not together), produce a number of offspring of both sexes to keep the pattern going, and both/all survive an environment in which they were unique. Also, they would somehow have to know, with only animal intelligence, that in order to reproduce they must mate, contrary to the "evolved" instincts of their forebears of self-replication - or else there must be another major mutation in each that causes a mutual attraction similar to animals being in heat, which is a different though related biological function. They would also have to know how to reproduce, know the mechanism by which they could combine their genetic code. And I am sure that there are even more complexities involved in even the simplest 2 sex species know to exist which I am missing.
Doesn't multiple sexes tend to support Intelligent Design better than evolution? (The reason I put this in R&S)