Is Sex Really Necessary?

Birds do it. Bees do it. But dandelions don't. The prodigious spread of these winsome weeds underscores a little-appreciated biological fact. Contrary to human experience, sex is not essential to reproduction. "Quite the opposite," exclaims anthropologist John Tooby of the University of California at Santa Barbara. "From an engineer's standpoint, sexual reproduction is insane. It's like trying to build an automobile by randomly taking parts out of two older models and piecing them together to make a brand-new car." In the time that process takes, asexual organisms can often churn out multiple generations of clones, gaining a distinct edge in the...