The Best American Science and Nature Writing 2011 (45 page)

What that means in practice is that space and time no longer give structure to the world. If you try to measure objects' positions, you find that they appear to reside in more than one place. Spatial separation means nothing to them; they jump from one place to another without crossing the intervening distance. In fact, that is how the imprint of a hapless astronaut who passes the black hole's point of no return, its event horizon, can get back out. "If space and time do not exist near a singularity, the event horizon is no longer well defined," Horowitz says.

In other words, string theory does not just smear out the putative singularity, replacing the errant point with something more palatable while leaving the rest of the universe much the same. Instead it reveals a broader breakdown of the concepts of space and time, the effects of which persist far from the singularity itself. To be sure, the theory still requires a primal notion of time in the particle system. Scientists are still trying to develop a notion of dynamics that does not presuppose time at all. Until then, time clings stubbornly to life. It is so deeply ingrained in physics that scientists have yet to imagine its final and total disappearance.

Science comprehends the incomprehensible by breaking it down, by showing that a daunting journey is nothing more than a succession of small steps. So it is with the end of time. And in thinking about time, we come to a better appreciation of our own place in the universe as mortal creatures. The features that time will progressively lose are prerequisites of our existence. We need time to be unidirectional for us to develop and evolve; we need a notion of duration and scale to be able to form complex structures; we need causal ordering for processes to be able to unfold; we need spatial separation so that our bodies can create a little pocket of order in the world. As these qualities melt away, so does our ability to survive. The end of time may be something we can imagine, but no one will ever experience it directly, any more than we can be conscious at the moment of our own death.

As our distant descendants approach time's end, they will need to struggle for survival in an increasingly hostile universe, and their exertions will only hasten the inevitable. After all, we are not passive victims of time's demise; we are perpetrators. As we live, we convert energy to waste heat and contribute to the degeneration of the universe. Time must die that we may live.

FROM
Ecotone

T
HE FEMALE GIANT ICHNEUMON WASP
flies, impressively for her near-eight-inch length, with the light buoyancy of cottonwood fluff, seemingly without direction, simply aloft. Despite her remarkable size, she is not bulky. Her three-part body makes up only about three inches of her total length, and is disproportionately slender; her thorax is connected to her abdomen by a Victorian-thin waist. Most of her maximum eight-inch span consists of an ovipositor half that length, which extends from the tip of her abdomen and trails behind her like a thread loose from a pant hem. Fully extended, she can be nearly as long as your
Peterson's Field Guide to Insects.

Her overall appearance of fragility—the corseted middle, the filamentous tail—portrays in flight a façade of drifting. But both of the times I have seen a giant ichneumon wasp she was on a mission, in search of something very specific: a single species among the 1,017,018 described species of insects in the world (91,000 in the United States, 18,000 in Wisconsin, where I observed my second giant ichneumon). To comprehend this statistic, there are many things one needs to know: the definition of an insect, Linnaean taxonomy, the function of zero, the imaginary borders of states and countries. The female ichneumon wasp knows none of this. Yet it can locate a larva of the pigeon horntail—a type of wood wasp whose living body will nourish her developing young—hidden two inches deep in the wood of a dead tree in the middle of a forest.

Charles Darwin himself, it turns out, studied the ichneumon wasp. He mentions it specifically in an 1860 letter to the biologist Asa Gray, a proponent of the idea that nature reveals God's benevolence. Darwin, on the other hand, swayed no doubt by the rather macabre details of this parasitic insect's life, writes: "I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars"—and then, as if to reach the layman, he adds, "Or that a cat should play with mice." The tabby that curls in your lap and licks your temple, after all, has likely batted a live mouse between its paws until its brain swelled and burst. And the larvae of the giant ichneumon wasp eat, from the inside out and over the course of an entire season, the living bodies of the larvae of a fellow insect.

Like Darwin, I think I have put to rest my belief in a beneficent and omnipotent God—in any God, really. Contrary to what I once believed, it is easy to let go of God, whose essence has never been more than ethereal anyway, expanding like an escaping gas into the corners of whatever church you happened to attend, into the breath of whatever frightened, gracious, or insomnious prayer you found yourself emitting. But it is much more difficult to truly put to rest the belief in an afterlife, the kind where you might get to visit with all your dead friends and relatives. It will not be easy to let go of your deceased mother, who stands in her kitchen slicing potatoes and roast, who hacks ice from the sidewalk with shovels; she is marrow and bone, a kernel of morals, values, and lessons compacted like some astronomical amount of matter into tablespoons, one with sugar for your cereal, another for your fever, with a crushed aspirin and orange juice. You love her. You mark time and space by her: she is someone you are always either near to or very far from.

Can people live without the comfort of a creator? I think so. But relinquishing God—the Christian God, at least—does not leave everything else intact. A lack of the divine probably means that when you die what you consider your essence will cease to exist. You will no longer be able to commune with the people you love. Choosing to live without the assurance of an afterlife, therefore, feels like a kind of suicide, or murder.

 

Most parasites do not kill their hosts. You—your living, breathing self—are evidence of this, as you host an array of parasitic microbes. Only about 10 percent of the hundred trillion cells in your body are really your own; the rest are bacteria, fungi, and other "bugs." The majority of these microbes are mutualistic, meaning that both you and the microbe benefit from your relationship. A whopping 3.3 pounds of bacteria, representing five hundred separate species, live inside your intestines. You provide them with a suitable environment—the right moisture, temperature, and pH—and feed them the carbohydrates that you take in. They shoot you a solid supply of vitamins K and B
₁₂
, and other nutrients. But some microbes, like the fungi
Trichophyton
and
Epidermophyton,
which might take up residence beneath your toenail as you shower at the gym, are parasitic—they benefit from you, but you are harmed in some way by them. In the case of these two fungi, you would experience itching, burning, and dry skin. But you've probably never heard of anyone dying from athlete's foot, because it has never happened. Successful parasites—parasites that want to stay alive and reproduce—in general do not kill their hosts.

The giant ichneumon wasp is one of a few parasites that break this rule. Actually, it is not a parasite at all; it is more correctly called a parasitoid because its parasitism results in the death of the host. This is not to say the ichneumon wasp is not successful. It can afford to kill its host because its host has a very fast reproduction rate. If we did not have the ichneumon wasp, we also might not be living in wooden houses, because the wood-boring insects that these wasps parasitize would probably have killed all the trees. The wasp might look formidable, but in terms of its ecological role, it is a friend to humans.

This is what it does: A new giant ichneumon wasp hatches from its egg in a dark, paneled crib deep inside a dead or dying tree where the pregnant female placed it. Nearby, or sometimes directly beneath the egg just deposited, lies an unsuspecting horntail larva that has been chewing its cylindrical channels in the wood for sometimes two years. The wasp baby latches on to the exterior of the caterpillar and feeds on its fat and unvital organs until both are ready to metamorphose into adults. Then, when the host has chewed the pair nearly to the surface of the tree, and the giant ichneumon wasp larva, which cannot chew wood, has a clear exit, the ichneumon kills and consumes its host. The wasp metamorphoses, possibly over the course of an entire winter, then emerges. Often before the newly metamorphosed females have even passed through their exit holes, they will mate with one of the plethora of males that have alighted on the bark for just this purpose. It's a kind of ichneumon
quinceañera,
a spontaneous debutante ball.

 

The problem of where I would go after I died began with simple arithmetic. In our family there were five—my mother, my father, my two older sisters, and me. Yet the world never seemed to divide by fives or threes as easily as it did by twos: I stood
between
the double sinks my sisters occupied when we brushed our teeth; the chair where I sat for breakfast, lunch, and dinner was pulled up to our oval table just for meals, positioned at a point not opposite anyone, and then pushed away when we were done—it didn't even match our first dining room set; I sat in the middle of the back seat of the car, while my sisters each got a window; and when we bought a dozen donuts, the last two always had to be divided, somehow, into five equal pieces—or three, which was no easier, if my parents were dieting. At some point in my childhood, for some unknown reason—I have asked them, and they still can't say why—my parents bought four burial plots. I couldn't make any sense of this. I worried. Where would the last one of us who died—probably me—be laid to rest? All I could foresee was my parents and sisters lined up neatly next to one another for eternity. All I could do was fear my impending, everlasting physical absence from the people I loved the most. Now that my sisters and I have married and they have had children and I have moved away, I realize the accounting error was not in buying too few but in buying too many: there will likely be two empty plots next to my parents. I've become accustomed to physical distance from my nuclear family by settling eight hundred miles from where I grew up, but the problem of where I will go after I die, what I will be like, and who will be with me has not gone away. It has only magnified.

 

Megarhyssa,
the Latin name for the genus to which the giant ichneumon wasp belongs, translates to "large-tailed." The species that I saw was likely the most common of the eighteen species of this genus,
Megarhyssa macrurus,
which translates to "large-tailed, long-tailed." These genus and species names, then, provide no information that an observer couldn't pick up in a single, fleeting interaction with the insect itself. The tail is more precisely called an ovipositor, an appendage used by many female insects—and some fish and other creatures—to place their eggs in a required location. That place might be soil, leaf, wood, or the body (inside or out) of another species.

The ichneumon's process of depositing eggs with her long ovipositor goes from mystical to complicated to bizarre. First, she locates her host by sensing vibrations made from its chewing beneath the wood. Her antennae stretch out before her like dowsing rods, occasionally tapping the bark, and she divines the presence of the horntail, catches it snacking like a child beneath the bed sheets who has made a midnight trip to the kitchen. She "listens" for the subsurface mastication of an individual caterpillar encapsulated in old wood.

Now the pregnant female begins the increasingly complex actions that will transport the eggs from her body through as much as two inches of woody tissue to the horntail's empty channel. Keeping her head and thorax parallel to the wood, which she grips with her legs, she first curves her abdomen under, into a circle, touching its tip to her thin waist. Her ovipositor, as if its outrageous length were not surreal enough, now performs a magician's feat: it separates into three long threads. The center one is the true ovipositor; the other two are protective sheaths that will help steady the insect's abdomen and guide the ovipositor as it enters the wood. (When she is finished laying and flies off, you will sometimes see these three threads trailing separately behind her.) The two sheaths, one on each side, fold back and follow the curve of her abdomen, then come together again at the very tip of her thorax and head straight for the wood, sandwiching her body in two broadly looped capital Ps. The ovipositor extends directly into the two sheaths where they join and disappears between them. In order to allow the ovipositor's acrobatics, the exoskeleton at the tip of the abdomen splits somewhat and pulls back. At this stage in her laying, with her ovipositors perpendicular to the tree, her wings flat and still, and her legs spread-eagle, the ichneumon looks as if she has pinned herself to the wood as an entomologist might pin her to a cork for observation.

 

Before we hang up from our once-weekly phone call, my mother says she has one more little story to tell. This one is about Kristen, my niece, at age five my mother's youngest granddaughter.

The week before Easter, she and Kristen drove to the church where my grandparents and my mother's little brother, who died when he was a baby, are buried. My mother wanted to put flowers on the headstones. Before they got out of the car, Kristen began talking about her own mother and her older sister, Katie.

"Mommy and Katie want the same," Kristen said, "but I want to be different."

"What do you mean?" my mother asked.

"I want to be buried," Kristen replied. "But Mommy and Katie want their bones..." She paused for a minute, thinking, then continued. "They want their bones burned." Kristen paused again, then concluded, "But, really, I don't want to die."