Undeniable by Bill Nye Page A

ourselves. I saw her at our reunion recently and she is still, as it is expressed in modern parlance, all that. I guess it’s seared in the proteins that create memories in my sex-driven brain.

 
    9
    THE TALE OF THE RED QUEEN
    In the previous chapter I discussed when sex evolved, and explored how sex evolved, but you may notice that we (or I) didn’t really address the “why.” Why does anybody—I mean why does any organism—have sex? The amount of energy we put into it is crazy. We spend billions on lipstick and hair product. About every third advertisement in any medium is for a car—one with plenty of sex appeal. We get our pants pressed, our nails done, and we work hard to smell nice—all to attract a mate, one that will enable us to have sex and offspring. Why do we go to all the trouble of attracting a mate? Why not just get this literally vital task done on our own? Why not just let our lips be lips and drive around in gray, featureless blob cars?
    It’s not as if sex is the only way to reproduce. We humans could, for example, just split ourselves in half, DNA, bones, muscles, brains and all, like any self-unaware, or perhaps self-respecting, bacterium. The separate pieces form new membranes and boundaries as they separate. A replica of the DNA from the parent is built on each side—I mean, inside each of the two individuals that emerge from the original. If it’s hard to imagine a person splitting in half that way, try picturing a genetically identical baby budding directly off of a mother or a father. There’s no reason why it couldn’t work in the big picture, yet here we are instead surrounded by all of those made-up lips, polished nails, fancy fragrances, gym memberships, sporty cars, and the like.
    And those are just the obvious examples from our human experience. Much more important, from a planetary perspective, are the billions of other species here on Earth that use energy from the Sun and the soil to build flower petals, pistils, and stamens—to build bioluminescent appendages—to grow fruit on their limbs just so some jerk like me will yank it free, cart it off, and spit the seeds out someplace, where they might find friendly soil and a place to grow some offspring fruit of their own. Why bother?
    Salmon swim and swim. They spend most of their lives eating other fish with the goal of finding a fish-mate that they can swim upstream with, lay a pebble bed, fertilize with milky sperm, and die. Why bother? You can try not to make jokes about it: A pregnant elephant takes up a lot of room, but getting an elephant pregnant looks like a good bit of difficulty. Why bother?
    Let me start by saying as of this writing, no one is absolutely sure why organisms like you, me, armadillos, and trees have sex. Broadly speaking, sex produces offspring with a new mix of genes, a mix inherently different from the parents. It may provide more chances for innovations, which might lead to a more successful successive generation. The new mix of genes might weed out genetic errors.
    But we do have an outstanding theory about why sex is useful, a theory that places sexual reproduction within the larger picture of the theory of evolution. It is survival of the fittest, survival of those that fit in the world, specifically the ecosystem that is best. It’s competition. And one’s chief competitors are seldom other troublesome large animals: Humans really have very little trouble keeping up with and living around lions and tigers and bears. Instead, our most troublesome bad guys are germs and parasites. These are what can kill us or disable us to the point where we cannot produce or care for offspring.
    We’re not the only organisms with this germ and parasite issue. If you lick your lips, you might ingest right around 1 million viruses that specifically attack bacteria. By long tradition, they’re called bacteriophages, or just phages for short. ( Phage is