Fragment by Warren Fahy

possibly even thermal energy venting in the dark depths of the ocean to fuel these metabolic processes.”
    The next slide showed a variety of simple forms that looked like primitive prokaryotic cells.
    “The first crude organisms collided and sometimes consumed one another, blending their genetic material. A minute percentage of these blendings bestowed advantages on the resulting hybrids.”
    Geoffrey clicked through images of waves crashing on shores.
    “If you combine extreme tides caused by the nearby Moon, which is still drifting about two inches farther away from the Earth each year, with the constant bombardment of ultraviolet radiation from the sun, then stir and cook the primordial soup for one and a half billion years, you get the most significant innovation in the story of life.”
    Geoffrey clicked the remote, and the next slide sent giggles through his audience.
    “Yes, my friends, it looks like a sperm cell, but it’s actually a tailed protozoan called
Euglena viridis.
It is an individual animal, a unique species, a single-celled organism remarkably similar to sperm. The primordial sea had produced the first creatures with the ability to
hunt
, using thrashing tails to chase down other single-celled organisms and consume them. Sometimes these first predators actually exploited the reproductive systems of their prey to facilitate their own reproduction—and sometimes their prey perpetuated itself by hijacking the genes of its attacker.
    “In either case, the proposition of tonight’s Chat is that these very first hunters and their prey created a new and mutually beneficial relationship that we call
sex.
When certain cells began to specialize in consuming or penetrating other cells for reproduction, others cells specialized in hosting reproduction itself, thus deflecting death and perpetuating both lines of DNA.
Sex is the peace treaty between predator and prey.
The offspring of theirunion not only combined the properties of both but carried forward each original single-celled organism, now modified as sperm and egg. So there you have the kindling for tonight’s Fire-Breathing Chat, ladies and germs. I submit that sex began at the very beginning with single-celled organisms. I propose that the answer to the age-old question, which came first, the chicken or the egg, is the egg… and the sperm.” Geoffrey stepped aside from the podium and bowed.
    Shouts came from the back of the auditorium. Uncomfortable groans rose from the scientists in the front rows, especially from the gray hairs.
    Geoffrey clicked to the next slide—a human egg wreathed by wriggling sperm—and he paused to enjoy the slightly nervous titter of recognition that the image always evoked from an audience.
    “Egg and sperm may actually be the living echo of a revolutionary moment that transpired a billion and a half years ago in the ancient seas of Earth. Indeed, I propose that this original love story has repeated itself in an unbroken chain since reproduction began in eukaryotic cells—that is, cells that have membrane-enclosed nuclei inside them. When the first hunter cells grew tails in order to chase down their prey, the hunted cells made peace, if you will, by absorbing the hunter’s DNA and facilitating its reproduction, thus ensuring both cells’ survival and turning a war into a partnership.
    “And since the sharing of genetic material led to a convergent variation in the morphology of their offspring, this innovation accelerated the evolution of superior forms in tandem, continuing to ensure the survival of both kinds of original cell in male and female carriers. And the elaboration of multicellular life issuing from that ever-accelerating partnership would launch both of the original organisms into wildly diverse environments.”
    The grumblings grew louder in the audience. Geoffrey raised his voice mildly.
    “I suggest that this proposition is validated each time sperm penetrates an egg and results in an offspring. All