From an evolutionary perspective, the cost of sex must greatly outweigh its benefit. To better understand the benefits that sex brings to the table let’s consider the costs. A mature individual capable of asexual reproduction is guaranteed to reproduce. Now let us imagine ourselves as a math nerd in junior high school. Suddenly the advantages of sex don’t seem so good, now do they?
The difference in power between asexual and sexual reproduction is like the difference between a billion computers all trying to solve a problem vs. a billion-node super-computer. If one of the solitary computers makes an advance, that’s it, the computer must then make another advance on its own. In the super-computer, all the nodes can communicate advances with each other.
In my last entry, Difficulty of Re-evolving a De-evolved Trait, I speak of the generally destructive force of mutation. Getting one beneficial mutation is extremely rare and getting two in one offspring is astronomical. I see the purpose of sex as a kind of good mutation aggregator. Let’s say the two most fit individuals of a population each carries a different beneficial mutation. Let’s say the mother has stronger legs and the father has stronger arms. With asexual reproduction it would take a strong-armed heritage a thousand years to discover the strong-legged mutation. With sex on the other hand the children of those two parents will have a good chance of possessing both strong arms and strong legs.