#1 OF THOSE WEIRD THINGS HUMANS DO,AND WHY WE DO THEM- HAVING SEX

#1. SEX
Everyone knows sex is how we reproduce. But why have two sexes in the first place, instead of a uniform population of asexually-reproducing individuals? After all, with twice the number of moms, populations of asexual organisms grow at double the rate of sexual organisms in lab experiments.

Biologists' best answer, called the Red Queen hypothesis, holds that organisms and the parasites that live on them are running a race in which they constantly evolve in response to each other's genetic mutations, maintaining an overall balance. Sex, the theory holds, gives host organisms a leg-up on this evolutionary treadmill by allowing two such organisms to shuffle their genes, creating new, rare combinations in their offspring and new challenges for coevolving parasites