...Sigh.
Male/female dichotomies exist in nearly all lineages in the multicellular eukaryotes and do so because that's /exactly/ what natural selection predicts would happen in that situation.
Say we have a diploid cell that produces haploid offspring, which fuse with other haploid offspring to produce mature diploid individuals (as is easily observable; currently thought to be an adaptation to avoid parasites as per the Red Queen hypothesis). In this situation, which haploid cells are most likely to survive? Naturally, the most viable are the ones with the more resources in them. In consequence, natural selection drives the increasing allocation of resources to the haploid cells over time, and they get bigger and bigger while fewer are produced.
At some point, they become so big that they are viable even on their own. At this point, a new strategy becomes viable - barely any resources at all, but thousands and thousands of cells produced, which could quite easily arise through mutation as do most "cheating" strategies. Thus there are now three possible combinations to create diploid organisms - small-small (majority, non-viable), large-large (super viable but extremely rare) and small-large (viable and common). Eventually the small-large become pretty much the only two strategies that work, and the cheaters cannot overpower the honest as they are dependent upon them.
At this stage, natural selection will not drive either strategy to elimination, as both are evolutionarily stable. In consequence, what is favoured is the ability for the cheaters to find the honest, and it is statistically very unlikely for an honest gamete to bump into another. Thus is produced anisogamy - two morphologically distinct and mutually dependent gametes for syngamy; come the evolution of multicellular organisms, this has been maintained.
Of course, this isn't universal, as even a cursory glance at an isogamous or parthenogenetic or hermaphroditic species might tell you. Every path is different and contingent on its own set of variables.
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... Now let's throw the question back at Mr. Lisle. Why, exactly, do we even have males and females to begin with, according to your Creation Hypothesis? Presumably it's something to do with that bit in Genesis about Eve being created to do Adam's bidding. Of course, that doesn't exactly explain the presence of females in other species; so why couldn't your God just make parthogenetic cows/ferrets/lizards/whales and eliminate mutations, if he's presumably an all-powerful God? Furthermore, why is it that the male angler fish is literally just a floating penis whose only purpose in life is to attach himself to a female as a source of sperm and, eventually, nourishment, as he is absorbed into her body; what part of this maps to the female angler fish being created to do the male's bidding?
It's almost as if you're basing your biological knowledge on a book written by a bunch of desert-dwelling savages whose knowledge of animals could be written on the back of a small envelope. But that's just my take on it.