Dating and mating may be tricky, but there's an evolutionary benefit.

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You only have to get your heart broken once to wonder why the opposite sex exists. Why must men be from Mars and women from Venus? Why must we live in a world divided by pink and blue? Wouldn't things be a lot easier if we were all one biological sex?

It's not as if a species needs both males and females to reproduce. A variety of organisms reproduce asexually, which is the route taken by protozoa that divide themselves into two identical copies. On the other hand, there are some species of mushrooms that have 36,000 sexes [source: Podger]. That means a mushroom's odds of finding something to mate with are much higher than yours on a typical Saturday night. So why are we humans and so many other species stuck with two sexes coming together to reproduce?

Much study has been done on species that can reproduce asexually and sexually to determine the benefits of each method. Asexual reproduction has its benefits: The whole process is much quicker than sexual reproduction, it yields a greater number of offspring, and it takes much less energy (goodbye, mating rituals!). It's also the perfect strategy if you love yourself just the way you are, since you can produce many copies of your precise genetic code.

But while that rationale works well with perfect specimens, it won't work well when something within the DNA mutates due to the environment. In one study of New Zealand freshwater snails, the sexually reproducing snails accumulated harmful DNA mutations at half the rate of the asexual snails [source: University of Iowa]. And while you might think that the best way to pass along the beneficial genes is to have one ideal specimen continually reproducing, a study of fruit flies found that beneficial mutations accumulated more quickly via sexual reproduction [source: University of California - Santa Barbara].

In other words, a style of reproduction that provides different sets of genes to the offspring is beneficial, but we can't go the way of those 36,000-sexed mushrooms. If you could mate with just about anything, then mutations would spread more quickly through an entire population [source: Podger]. Though mating rituals seem tedious and impossible, we need the process to be a little difficult to prevent dangerous mutations from affecting entire generations.

So while our two-sex system might seem rather inefficient, and while tons of ink has been spilled as one sex tries to figure out the other, the current meeting of one woman and one man in the reproductive game is what's best for our species. Each sex brings different genetic code to the table, giving us better odds in the genetic crapshoot.