When I find a horseshoe crab on the rocky beaches of Great Peconic Bay, I never know if it’s alive or dead. I walk past it as I would ravaged whelks and pebbles and sea glass and clamshells and seaweed. There it lies, Achilles’s shield, a rock, an oversized bug; there it lies, turning metal hot with the sun, cold and invisible on a starless night long after the living thing inside has died. I kick over a shell, dappled with parasitic flatworms and slipper limpets, and find tidy rows of triangular gills like so many delicate shoulder blades.
This crab doesn’t scuttle along the shores of silent seas because it isn’t, technically, a crab. It’s more closely related to scorpions and spiders. Often referred to as a fossil, which I think of as a rock with the impression of a formerly living thing, it has a phenomenal capacity to survive. The horseshoe crab is virtually the same as it was nearly half a billion years ago; it existed before dinosaurs, and endured as they died off. One factor in its survival may be its blitzkrieg defense system, whose arsenal resides in the blood. Instead of hemoglobin to carry oxygen, this blood has hemocyanin, which sounds strangely lethal, but simply means it contains copper, which lends it color the way a copper drainpipe turns bluish green. The critical element, though, is Limulus amebocyte lysate (LAL), which detects bacterial endotoxins even in concentrations of one to a trillion, and when that happens LAL bolts into action, surrounding, choking, imprisoning the bacteria in goo for as long as a few weeks. The crabs don’t have circulatory systems as we do. Any crack in the exoskeleton opens the way for bacteria to enter and pervade, but at that point the blood releases granules of LAL, which leave the bacteria in a quagmire, neutralized.
Not surprising, humans have gotten in on the action. Five laboratories in the US harvest the crabs, alive, strap them to a metal bar, pierce the tissue near the heart and drain about a third of their pale-blue blood before releasing them. When medical companies develop new drugs and prosthetic devices that come into contact with the blood, they test samples for bacterial infection by subjecting them to the horseshoe crab’s coagulant. In short, any American who has ever gotten an injection is safer because of the horseshoe crab.
Bleeding proponents claim at least two-thirds of bled crabs do just fine once returned to the sea; some say only 3% of the crabs die. Environmentalists reveal higher mortality in the short-term, and further, more nebulous loss in a nebulous future since females, weakened by blood deficit, may not climb onto shore at the optimal time to lay eggs, or may not get there at all. Their current status is NT, Near Threatened. Not Today, maybe tomorrow.
When the tide was out recently, I found a huge one far up the beach, its shell dark as a blacksmith’s forge and coated in seaweed and slipper shells. I picked it up gingerly, stunned by the weight and unsure if it were alive, and if it were, if its pincers could reach my fingers. As I held it up to the sunlight, two legs moved ever so slightly and slowly. I had disinterred a corpse bent on resuming life in some singular dimension of time—and then the tail, this stiff sharp spear, rose perpendicular to its body—was it more alarmed than I? I walked to the shoreline where I set it down, right side up, and looked for its eyes, tried to look into its eyes.
Later I learned the crab could have righted itself. The spear is not a weapon but ballast with which the crab flips itself over in the sand. And those lightless bumps on the prosoma, or head region, which I could scarcely detect, are compound eyes with 1,200 surfaces like those of a fly that see hundreds of images at once. They look like a honeycomb, and each eye has rods and cones a hundred times the size of ours. The nocturnal crab has five more eyes on the carapace, which I totally missed, and two on the ventral side near the mouth, which may help orient the crab while swimming. Horseshoe crabs see visible light and ultraviolet in sun and moonlight, which keeps it in tune with lunar cycles, so the female knows when to clamber up onto the beach, nestle in the sand, and lay eggs for gang fertilization. Add to this: light sensors along the tail synchronize the animal’s brain with shifts in darkness and light. It sounds like being a horseshoe crab is a veritable light show—streaks of ultraviolet intersecting with spectral blues, reds, greens, all charged with information about spawning and feeding on crustaceans and mollusks on the ocean floor—and yet there it lies, looking scarcely animate, a bit of alien mystery washed up on shore by an ancient sea when pterodactyls not seagulls winged overhead. But I’ve read this survivor has lousy vision; it’s not 20/20, which is perfection as humans define it.
Years ago, when I gave birth on the night of a full moon in early May, I didn’t think about a hefty horseshoe crab on the beach laying 2,000 eggs, about smaller males crowding around for a chance at even anonymous paternity, about sandpipers pecking at the feast. “The maternity ward is full!” reported my midwife who darted from room to room. Two weeks late, my baby rode high in the womb, resisting all medical anxieties and predictions, and I was scheduled for a C-section the following morning. But the tug of the moon must have rippled through me unawares, sending me into labor (as it did so many other mothers, other babies), and now I wonder if horseshoe crabs that night were more conscious than I of the timing to give birth though consciousness sounds ludicrous when associated with a crab. Then again, how often do I operate on sensory or intuitive impulses that have not quite nosed the surface of consciousness and either delude myself that they have or admit to having no idea why or if I did what I did?
I ended a three-year relationship because a certain smell turned me off. Suddenly. Subliminally. Irrevocably. It didn’t even feel like my decision.
I’ve sat on temple floors and church pews and stared at multiple incarnations of Buddha, the graphic martyrdom of Saint Sebastian, the tender astonishment of Mary in Da Vinci’s Annunciation, all with an inclination to be transported, all with the indefinable sensation that mind exists distinctly from matter, when a rational rejection of things intangible and divine slams like a ceiling attic door with Bessler stairs pulled up and out of sight.
I’m left with the weight of a horseshoe crab in my palms, a handful of sand, my own finite being, all this physical matter, one human body comprised of pretty much the same elements as another. Yet, if I prick my finger, and yours, I know what it feels like to me but can never know what it feels like to you. And what of death, or love? That even shared experience of the world is intricately dissimilar at the very least suggests the existence of something not reducible to the darting about of atoms. I find it astounding and strangely comforting that over the course of evolution, we have no idea when consciousness arose. We know that simple things gave rise to more complex things, but since we can’t pinpoint a moment, and can’t argue physically that something appeared out of nothing, then we have to assume continuous development. In that case, we today with all our sophisticated technologies share something quite mysterious with an amoeba.
At the age of four, my daughter (who happened to be very conscious of her own being as female) asked, “Does a dog know it’s a dog? Does a dog know another dog is a dog?”
“Good question!” I stalled. Should I tell her, No, a dog does not know it’s “a domesticated carnivorous mammal that typically has a long snout, an acute sense of smell, and a barking, howling, or whining voice” as the dictionary informs us. Nor does a dog think it’s “a person regarded as unpleasant, contemptible, or wicked,” which writers of the dictionary have inferred is the connotative meaning. But how can I be sure? My dog used to go to the door and scratch so my husband would get up from the most comfortable chair in the room to open it, whereupon the dog would wheel around and dart to the chair, curl up, and snooze. So although I doubt the dog applied a moral judgment to its actions—sneaky, manipulative, Darwinian—it knew it liked the chair as much as my husband did, which gives them something essentially in common that might blur the line even infinitesimally between dogness and humanness. And by generally accepted definition, we are conscious beings. Can consciousness of comfort and consciousness of self be mutually exclusive?
What does a horseshoe crab sense when a medical technician strings it up like a prisoner of war and leaves it hanging for indeterminate, non-self-determined, periods of time? What sensations dart through its blue blood before it drips, drips, drips into a glass jar? Does it sink into a dormant state—numb, near paralyzed—as people do when traumatized? A New Yorker article reported that Syrian teenagers whose lives were decimated by war have fallen into coma-like sleep that lasts for months, even years, in the face of hopeless lack of control.
In a rational world, I don’t know why I find the photos of bleeding crabs so disturbing. Were they not so valued for their blood, governmental protections would be lifted, and fishermen would revert to mass slaughter of the creature for use as bait to catch conchs. In the twentieth century, populations declined at a fever pace when horseshoe crabs were steamed, chopped up, ground into meal, and spread as fertilizer or fed to hogs. Were they not so prized, pharmaceutical companies would still be testing rabbits, which horrifies us more since they have warm brown eyes that meet our own and look picturesque hip hopping among the hydrangea. Perhaps it’s the collision of eons marking this creature’s history and our medical needs for tomorrow, the stark eradication of millions of years hurling themselves on the shore only to recede limply back to sea, that strikes me as sacrilegious.
Mere decades have passed in my daughter’s life, but now she has grown up and is ready to have a baby. Because of her genetic history, doctors may harvest her eggs, make the miraculous match, evaluate the embryo, make a godlike selection, and implant it. They may intrude upon her cycle and intervene in the lunar one. Or perhaps she will make a different choice. Had we done genetic testing on her before her cells multiplied and she grew into the vibrant being she is, she would not be alive and the world would be a lesser place. With knowledge comes responsibility, sometimes more than we want to bear.
I stand on the shoreline wishing only possibilities of motherhood for my daughter, which happened for me so effortlessly, unconsciously, in a tumble of sweat and flesh one night in a rented cabin by the ocean. As my feet crunch on scallop shells and pebbles, I wonder why I found four or five exoskeletons of horseshoe crabs last week and this evening none. Where do they go as the days grow shorter? On what early morning when I’m sleeping will they know to waddle up on land and spawn, and how many eggs will survive? I have not seen this, nor have I seen the blue blood that has saved millions of anonymous lives.
Limulus polyphemus, how ugly and strange, your name the same as the not so bright Cyclops whom Odysseus outwitted. But then, that giant had one eye with which to navigate, not ten, and that giant drank himself into an unconscious stupor. Odysseus instigated his escape as Polyphemus slept; at another time, Odysseus’s men killed the Cattle of the Sun against his instructions and with dire consequences as Odysseus slept. The Greeks advised wakefulness; sleep, it seems, is oblivion, loss of consciousness, loss of control, and for Polyphemus, loss of sight.
Because of the horseshoe crab, I wish to have eyes in the soles of my feet or along my ribs or the back of my head since apparently it’s not impossible. The crabs swim upside down, their underbelly eyes picking up light shafts slanting through the water, while eyes on the carapace search for worms and crustaceans below. Imagine! What panoramas! What sights when the wind whips up behind you and flips green leaves to silver while a single leaf flickers down before you, tilting and turning so strangely like the brown butterfly there braving an October wind. You see it all (and all is irreducible, since the eye cannot block out half a frame), and it wouldn’t stop even as the wind dives beneath your conscious mind and whispers unintelligibly of things extinct and things unseen.
