WHEN MY SUMMER FUN appeared to be gone, I did what all humans do when their fun is gone. I looked around for something to blame. I picked up the phone and called Evie, who as a biologist was interested in the whole story, up to my sighting of the male Foster Fowl, and as a sibling, was amused at the thought of her older sister acting like a nitwit.

"Wow, that was really stupid," she said. "Cowbirds are evil? Compared to, like, humans?"

"Do you think they'll ever come back?" I begged.

"Um, Sophie, I would guess that your birds are over-producing females, which species do in hard times. And this heavily female population is moving north, because their habitat's screwed up. That's what ornithologists call the escalator to extinction."

I imagined an escalator on which grinning human skeletons, clutching handbags, rose into a dark department store.

"What that means," Evie continued, "is like, birds follow the plants and animals they eat into cooler climates. The farther north they go, the worse they do, because they're going into conditions for which they haven't evolved. The thing is, your females don't sound very weather-resistant. So if they're dying in the winters up here, that puts, like, more pressure on the species. Which, in response, produces even more females, who die in the winter. You follow?"

"Yes," I said, repressing the urge to say I wasn't stupid, because I was.

"The species gets thinned out. It's a vicious circle. If climate change weren't happening so fast, maybe they'd adapt. Like, a mutation could produce hard-feathered females who could survive the cold. As it is . . ." A near-audible shrug. "Some of my colleagues think that global warming will wipe out like thirty percent of land-bird species in this century."

"Are you joking?" I croaked. "Look, I know you think I'm crazy. But please."

"You," laughed my sister, "totally have an imagination. And you care about animals. You know what I think? Without imagination, we can't stop extinction. That's the main problem with getting people mobilized. Thirty percent of land birds-it's not just about, oh, I don't see my woodp.e.c.k.e.rs at the feeder, oh, I can't bag my pheasant, whatever. It's not about fun. It's about survival. Because a bird touches so much-the plants it pollinates, the organisms it eats, the predators, the whole incredible cascade of species it affects. I mean, ma.s.s extinction is incredibly dangerous. But for most people-hey, the world is full of animals, the sky is full of birds, like-n.o.body has to imagine life without them." Evie spoke with pa.s.sion, which made her sound like someone with pressing errands to run. I was standing in the sunlit porch, phone in hand, hanging my head. Shadows of leaves trembled over the stone floor, as if fossil leaves, embedded in the slate, were struggling to surface.

THE BLAME FOR LOSING the Foster Fowl fell squarely on me, the only human being who had seen her, yet taken her for granted. Why hadn't I trapped one, built a rookery, nurtured a breeding pair? Why hadn't I used my special gift of seeing the invisible to protect what others couldn't see? It would have been no more than what naturalists and biologists do when they try to protect some unsung creature performing the work of life, some necessary being that lacks the allure of a politician's face, an entertainer's b.r.e.a.s.t.s, or a soldier's corpse. The longer I reflected, the larger loomed the loss. I missed my fun, then I mourned the Foster Fowl's absence in the world and would have been overjoyed to know, sight unseen, that she still existed, rearing the abandoned young of others. Then, gradually, the grandeur of the chance that I had squandered became apparent. If My Blue Heaven could teach a duck to swim, an owl to hunt, and a vulture to scavenge, what might a human being have learned from her? We don't really know what we're fit for, what human nature really is or might be, but we do know that our nature fits into the s.p.a.ce created by all the other animals, a particular wisdom learned among them, and the Foster Fowl was the best teacher of them all. Too late!

Reader, when I die, and my soul goes to be weighed, when my soul is weighed as the Egyptians prophesied, on a scale against the weight of truth itself-a single feather-which way will those scales tip? I don't know. You tell me.

*I did try to find out if Foster Fowl chicks were being hatched out here by tweezing apart the regurgitated pellets lying under owl nests. I probed the pellets of short-eared owls, great horned owls, and Owls of Aurora (invisible owls that hunt at daybreak, although their skills are far more suited to nocturnal hunting, so they don't do too well, but never learn any better). No owls were regurgitating Foster Fowl bones.

4.

Picture this allegory: Two angels stand on either side of Evolution's throne, each holding a symbol. Compet.i.tion holds a lamp that, like a predator's eyes, shines on the circle of creatures favored by natural selection. Symbiosis holds the rainbow, whose arch spans the horizon of the living earth. Around Symbiosis's feet grow flowering plants that co-evolved with pollinating animals. Symbiosis's trailing sleeve is beaded with tiny eukaryotic cells, from whose merging of bacteria and archaea all the earth's plants and animals spring. Without Compet.i.tion-chaos. Without Symbiosis-nullity. This is a tale on the side of Symbiosis, and I have mentioned angels because when I ponder the existence of the soul and spiritual things, I think of Beanie Sharks.

Beanie Sharks IT WAS ON THE TOP FLOOR of a natural history museum, where they keep the artifacts of oceanic tribes, on a rainy afternoon. There were pools of light, and in one of them a display case, and near it a bench on which I sank in disbelief. I went back up to the case, put my hands in my pockets, craned forward again, reread the typed labels. I stared at the remains of an animal that had been miscla.s.sified as "ritual object, or toy." Then I returned to the bench and tried to absorb what I had seen, hanging my wrists over my knees and staring at the floor. To know that an extinction is coming and be unable to sound an alarm, because the creature is invisible . . . But most beasts are invisible, more or less-people don't know about them, or don't pay attention to them, and then they disappear, invisible forever and to everyone. It's no consolation to think that even if most people saw invisible beasts, they still might not care.

I got up again, went over to the display case, and looked at the remains again, the way you look and look at the accessories of a pet who has died. Or the way people look at a stuffed extinct animal, like a moa, arranged by a taxidermist to seem capable of coming back to life, so that we lower our voices and suppress notes of wonder, as if the beast could hear us, which is what we really want-after all, our murmurs tell the stuffed corpse, we can see you, know you, so you must be here, not altogether gone? Surely you are still somehow here? But the stuffed thing doesn't move from its wired spot in the museum diorama. Thanks to the longevity of museums it will likely outlast us, and when we're dead and buried and in the carbon cycle, it will be still sitting with its moth-eaten fur, its desiccated feathers, its upholstery scales. Of all humanity's monuments-ideas, structures, artworks, devices-the ones that represent us most enduringly are those unique and eternal absences, the extinctions.

I knew this animal. It looked like a beige porcelain Frisbee, and was the sh.e.l.l of a giant limpet attached, in life, to a much bigger, invisible beast. Half a partnership lay in the display case, between visible and invisible. Morosely fingering the plastic museum pa.s.s that couldn't be shredded, and shouldn't be chewed, I sighed. What if our own bodies had invisible parts, unseen symbiotic partners who helped us function? Not souls, exactly. They would be animals, as real as the invisible Beanie Shark, whose visible partner, the Cap limpet, lay here. The parquetry squeaked as I leaned forward, breathing on the gla.s.s. "Unknown ritual object, or toy." I didn't know what made me sadder, the Cap limpet, sedulously mislabeled-or its Beanie Shark, somewhere in the ocean, bereft of a partnership that after hundreds of millions of years was now dissolving . . .

THE OCEANGOING FISH are hard to know. The original vertebrate lineage, they dwell in life's essential sphere; if you broke the continents and melted the volcanoes down to stubs, nothing much would change for them. Yet when we think of human babies, we ought to think of sharks. They are the animals who most closely resemble us in embryo, reports a Harvard biologist. Shark heads and human heads develop very similarly, from four embryonic scallops called the gill arches. Each gill arch develops into an area of the human, or shark, head; and each gill arch contains genes that direct its development, so that sharks become sharklike, while humans become humanlike. Bones that become jaws in a shark, become ear bones in a human. (A very bad sonnet by Keats says that his ear is open "like a greedy shark"-technically, he wasn't far off.) In embryo, humans, basking sharks, and Beanie Sharks look exactly the same. A Beanie is an invisible basking shark, and would be identical to the visible kind if not for the giant limpet, programmed to grow along with it, that tweaks its genes in embryo. As a result, the Beanie's head is altered slightly. But first let me tell you about basking sharks, those n.o.ble fish among whom I've swum while scuba diving off the coast of Scotland.

We do not know how many are left alive. They've been overfished for centuries, thanks to their slowness, lack of aggression, and plethora of uses. We make basking sharks into leather, oil, shark's fin soup, and shark cartilage, a reputed aphrodisiac-ironically, since basking sharks swim in s.e.x-segregated groups, like holy orders, and have been observed to inspect our boats from a distance, not sure, perhaps, if they've detected a potential mate, with all the awkwardness of habitual chast.i.ty. There are many things about them that we do not know. Here is a partial list: 1.Why only the right ovary of the female appears fertile, 2.At what age and season, exactly, mating occurs, 3.How often they breed, 4.Whether the gestation period is one, two, or three years, 5.How many young are born to one mother, 6.When they become mature.

What we do know is that basking sharks are creatures of peace. Twenty to forty feet long, they swim slowly, at two knots, their pectoral fins-the a.n.a.logue of our arms-relaxed, their bodies insinuating a continuous S, with an occasional strong flick of a lunate tail. Their mouths gape to scoop up plankton blooms. Those yawning mouths are cavernous; torrents of water and small life stream through them, like crowds through the pillared portals of medieval cathedrals, which, with the ribbing that soars up their inner cheeks to the vault of their upper jaws, they resemble. Viewed from below, their long-snouted, bulging heads look like shadowy onion domes; from above, their smooth heads are bordered with five gills, like flying b.u.t.tresses, lined with baleen filters. In immense tranquility they swim, gripped by mighty, unending yawns, perhaps sleeping in motion, for they are very simple: they cannot pump water across their gills and must swim to keep breathing; they lack swim bladders too. They make do with little. They swim into a human imagination like the swelling unison and subsidence of monastic chants, and the devotions of silence.

These inoffensive creatures were officially declared a nuisance, and fished aggressively, by the United States and Canada from 1945 till 1970, but are now protected by several nations.

The Beanie Shark is not protected, though. It suffers from ocean acidification, the result of excess carbon dioxide, as everyone knows. I try not to blame my elected representatives for ignoring my e-mails about this, from my technical-with-bibliographies-attached ones, to my pithy-screaming-caps ones, to my most recent ones headed $&SX4U. I understand that my government is composed of real people, ordinary, real Americans, just like me-as they always insist on TV-so how can they, in their echt similarity to me, be expected to solve the very problems I cannot? Anyway!

The oceans are turning acidic, and because of it, creatures who make sh.e.l.ls out of calcium carbonate are failing to make sh.e.l.ls. Corals that once towered from the ocean floor like t.i.tanic conglomerations of rainbows are now dead and bleached. If the imperial corals succ.u.mb, what becomes of the humble Cap limpet?

The Cap, about the size of a steering wheel, sits atop the Beanie Shark's enormous head. When the shark rolls over or dives, the Cap stays on, and the monumental fish resembles a member of an old-fashioned lodge with funny headgear. The Cap is anch.o.r.ed by filaments of its digestive tract, which follow grooves in the shark's head leading to its mouth, where they skim off some of the captured plankton. It's an easy berth for the Cap, siphoning its meals from the Beanie Shark's mouth. Yet this limpet is no mere parasite. It helps its giant companion by performing two special tricks.

When plankton blooms run thin, the Cap performs the propeller trick. Attached in an upside-down position, it opens its lid and sticks its foot up in the water. The foot unfolds into four paddlelike limbs, called parapodia, that beat the water, creating a whirlpool to trap plankton and lead them toward the shark. Many gastropods that live in the sea have such parapodia: the sea b.u.t.terfly's foot divides into two pretty, flapping lobes; the sea angel's parapodia look like rosy wings. While the Cap's propeller trick is within the norms of gastropod creativity, its second trick, the bubble wand, is more remarkable. For this trick, the Cap also opens its lid and sticks up its foot, but instead of paddles, it ejects a long string of spherical sacs, made of thin mucus membranes, which puff up into cl.u.s.ters of bubbles. These a.s.sist the Beanie Shark in maintaining buoyancy as it swims, though I am not sure what trigger causes the limpet to blow bubbles. Mollusks have their little ways, as any pearl farmer will tell you. One way or another, the Beanie, a simple basking shark with no refinements of its own, knows that when pickings are slim, its symbiont will lend a helping foot.

The Cap has not gone unnoticed by humanity. It washes up on land, from time to time, so I am not surprised that Haeckel drew it-though he called it a "barnacle," and drew dots and paisleys all over it, giving it the dandified appearance of a propeller beanie worn by Oscar Wilde.

IF WE EVER HAD A CHANCE to understand this intriguing pair, the visible limpet and the invisible shark, it is pa.s.sing with the acidification of the oceans: the Caps are dying, unable to form their calcite sh.e.l.ls. For tens of millions of years, this symbiont has tweaked the Beanie's genes, in embryo, ensuring that the shark will develop the limpet's comfortable seat on its head. The exact nature of that process will likely remain a mystery. At a wild guess, it may be connected to the malfunction of the female basking shark's left ovary. Possibly, the Cap influences the growth of all basking sharks, but is only successful with the invisible kind. How can we know, how can we ever understand, when these deft symbionts are cruelly dissolved by the very water that used to nurture their whirling paddles, and their enigmatic, joyous bubbles?

As for the Beanies, well, sharks have been around for a long time and nothing much fazes them. I suppose the Beanies could evolve into a race of invisible basking sharks with slightly deformed heads, and slightly fewer advantages. Yet it's hard to believe that they will not in some fishy sense pine for their loss, when the plankton blooms run thin, or when they're tired and heavy on their fins. Habits favored and selected for, for millions of years, can hardly be shed in a few seasons.

I'm tempted to describe the post-limpet Beanies as lost souls, since they're invisible and have such a spiritual lifestyle. And because they're detached from the visible bodies of their Caps. But that comparison would miss the point. After years of studying invisible animals, I believe that there is no spiritual aspect of our life that is not, simultaneously, animal. And animality is symbiosis. Our bodies are "integrated colonies" of cells, says a renowned biologist; and beyond the mergers of lone cells into animal bodies are the partnerships between animals-the goby cohabiting with a blind shrimp that it a.s.sists, the wra.s.ses cleaning parasites from a grouper's jaws. There are the mutual aid societies of all animals with their gut flora. And beyond animality lies the plant kingdom on which animals depend for food, the kingdom of photosynthesis, which itself sprang from an ancient partnering of blue-green cyan.o.bacteria and eukaryotic cells . . . The blooming gardens of earth and sea depend on symbiosis, the sharing-out of life's problems among many kinds of beings and their abilities.*

So if our bodies have invisible parts-call them souls-they would surely be animals. They would be the symbionts of a creature who sometimes claims to be the image of G.o.d, and in embryo resembles nothing so much as a shark.

*"Human beings are integrated colonies of ameboid beings." In What Is Life? by Lynn Margulis and Dorion Sagan (Berkeley: University of California Press, 1995) p. 141.

5.

The present, or Holocene, ma.s.s extinction is not the only one in life's history. It is the only one caused by a single organism capable of seeing the big picture, understanding its own destructive role, and changing that. But we don't see the big picture unless it's shown to us. Once, I had a moment of fortunate epiphany-a moment granted sometimes to naturalists-when the big picture comes overwhelmingly together, and you actually see the meaning of Lynn Margulis's apothegm: "Life is its own inimitable history." If I saw the big picture, though, it wasn't accidental: it was because I had to make a choice.

The Golden Egg THE DAY COMES WHEN I walk home through a waist-high meadow of panic gra.s.s, goldenrod, and lace saucers of wild carrot, and I see, as if I had startled it into being, a plane of green glittering moving leftward like a perturbed school of fish in the clearest of waters. I walk where those newly falling leaves drift by, and have to make up my mind whether a russet flutter in the gra.s.s is a monarch b.u.t.terfly or a dead leaf-the last of its season, or the first? I've been visiting with my neighbor, a farmer, who has found a nest of dead, half-formed bluebirds inside sh.e.l.ls so thin they burst at a touch. She's wondering what caused it-no pesticide she's aware of, but who knows, these days, what gets in the water? We both have wells. I've promised to check my birdhouses . . . but instead, lazily, I'm climbing down the side of the quarry, gray and cracked as shelves of unfired clay, lichen-rusted, blackened where my sunken pond has burned it with life. Sand curves between the rockface and a peeling carpet of water lilies. A little mite is headed up and down the edges of a lily's petals, so burning white they're gray where a candle flame is blue. Hoof-prints in the mud show where a doe and her spotted fawn have stood, immersed to their hocks, chewing salad; dried lily stems litter the beach. In the water, my head is a brown shadow through which glide the grim torpedo shapes of the pond's top predators, the ba.s.s. Poison? When I look up, a crevice in the rock winks, an amber wink, and there is the Golden Egg, never seen before, yet recognizable as nothing else. Many animals live and have lived at my home address, but this one has no peer. In a waxy, ochre body the size of a lychee nut, it holds what the human race craves: riches and longevity.

The-my-Golden Egg is tightly wedged into its crack; I see where the rockwall flaked, a pale scab, to reveal its tawny inhabitant, which has likely sat there since the glacier melted. Should I pluck it out? Should I go get a screwdriver and pry it out? My hand reaches, unsure of its next move; knowing as much as anyone does about Golden Eggs, I'd guess this one needs help. But against the limestone sunned to pumice-gray, my raised hand reminds me of those red handprints in the most primitive cave paintings. I don't know much, do I? All around, crickets, katydids, and nameless summer bugs are raising a song like the spinning of bicycle chains, louder and louder. It feels as though the deep past is revolving over the face of the pond, a dazzling wheel, on which tiny images of creatures appear and disappear, bringing together a minute Golden Egg and a miniscule human hand for a fraction of a sliver of a second. My spine hairs rise in the breeze; in a moment, the wheel will have turned. I will have done good or ill. In the meantime, it's a story wheel.

The story begins at my home address.

A SHINING, FOUR-FOOT-DEEP ocean, mighty and pretty as Venus, lies across the continent. Corals flower in the place of cities, and all creatures live and die in sunbeams dusted with tiny crustaceans. The Golden Egg is flat, drifting along like sc.u.m on a pot of boiled beans. It isn't much; with ambition, it might have been a sponge. But when a trilobite nibbles its edges, our drifter becomes a revolutionary-it rolls into a ball and spins away, sending ripples of frustration through the trim, fringed chitin of its foe. Now that they're aware of each other, nothing is the same, and all the rest follows, all those irreversible changes that go forward on hunger and a touch (whatever it means, to whomever it is happening) within the balance of life; the changes that will make the Golden Egg the most fortunate of animals. Starting with a major extinction. The first land plant, inching up on its rootlet, dropping its seed, forms forests thirty meters deep whose roots, cracking rock, swell streams with minerals, the first fertilizers-until algae smothers the seas, and the surf falling on all sh.o.r.es is a pounding dirge for three quarters of marine species. That is the price of seeds. The trilobites are diminished; in their absence the Golden Egg dares to a.s.sume its present size, bobbling along more heartily, eating more, being eaten less . . . never to lie flat again, it becomes, like everything, the shape of a relationship. One that's just getting started.

Meanwhile, our ancestors are beginning to make the meeting of a human hand and a Golden Egg possible, as six-foot dragonflies skim the scaled trees snaking up, from roots bedizened with mussels, into the torrential fronds of future coal reserves. Through the shrubbery troop our forebears, four-footed beasts who squat and dig like mad. If your ear was laid to that fat soil, you'd hear the champagne-cork popping of plopping eggs, the rubbery shot with which animals are conquering the land. The price of eggs will be paid in about 290 million years, with another major extinction-look around you! . . . But I digress.

In the saw-blade shade of dripping cycads, the Golden Egg makes progress too. It is still life's simpleton, a mere sphere. Only now its soft skin contains a stony bubble, made by the bacteria that mineralize its wastes. Wrapped around its digested and crystallized experience, it has a tougher style, but must face, very soon, the contradictions lurking in self-containment. Meanwhile the earth, too, becomes hard-hearted. From her equator to her poles sprawls the super-continent, Pangea, with its overheated interior, dynastic droughts, burled deserts, and gravel gorges where half-ton creatures trudge along and wave their creaking dorsal sails. Our friend the Golden Egg sometimes gets carted around in a gizzard, waiting to be cracked-an extreme approach to the problem it has now, of being as hard, inside, as firebrick. When it feels s.e.xy, it fertilizes its inner cavity (don't ask) and a second Golden Egg begins forming. But until the parent membrane can be shed, its sh.e.l.l cracked, and its young freed, the two concentric beings suffer in limbo, unable to bring new out of old, rebirth out of fulfillment. A breakthrough is needed, so be grateful for genius in the world!

They have cla.s.s-trilobites do. They are a cla.s.s. An evolutionary elite, from the get-go they never resembled any other creature except their supremely successful selves, beginning as shiny ovals that curl up with a perfectly interlocking fringe. On this they riff. Barbed, smooth, blind, bugeyed, with legs like running mascara, with heads like scimitars, without heads. They go planktonic and float and have Zen; they go big as your arm and whack the h.e.l.l out of their prey; and through it all, they l.u.s.t after, cannot stay away from, cannot stop chasing the Golden Egg. Why does the genus Walliserops evolve a vicious trident atop its head? "For male display," suggests a source, but I'm not so sure. Those tridents are Egg forks, the cutlery of the cultist, the maven, the devotee for whom a delicacy holds the very flavor of life. Against the Golden Egg's slippery toughness, the trilobites surpa.s.s themselves: gnawing off the outer skin, they let the hard sh.e.l.l turn brittle and crack, and its inner progeny escape. Without their bravura gusto, the Egg has no future; without its toothsome sphere, the trilobites lack temptation. They're made for each other!

But as these things happen, everything changes for the worst.

It cascades like the evil plot that it isn't. Volcanoes spewing lava across Siberia are not foreknown as their basalt cools into black cobbles, the Via Appia of death. Dust clouds are not designed, nor acid rains that foam and pit whatever they touch. When the globe heats up, and methane steams from the seabed, heating the globe even more, and the seas suffocate (again) till the only survivors are sulphur-eating bacteria, so the biosphere can almost be smelled from s.p.a.ce-a huge, blue, putrid egg holding a dying 99 percent of species (and for each, there is a last animal who wanders, calling and calling, and lies down by a bank of turf that, for all its strength to rise, may as well be on the moon)-well! None of that is ordained. Nothing can be concluded except the fact that changing the global climate leads to extinction as night speaks unto night.

Yes, I think of Penelope reweaving her web. But there is no going back to zero, there is no going back, period, even reverses and repet.i.tions are forward momentum, life's rhythm of and-because-and-because, the purest form of history.

And the trilobites, with three hundred million years of heritage, ten orders, one hundred and fifty families, five thousand genera, and twenty thousand species-have perished to the last mouthpart. Prolific even in death, their species are still multiplying in the fossil record, being counted and cla.s.sified by a strange beast with a skimpy past and uncertain future. The last trilobites are modest, shrunken, like the prints of fingertips. Requiescant.

Now the Golden Egg endures a time of supreme trial. It teeters, figuratively, on the narrow, wind-scooped ledge of evolution's dead end. Its numbers plunge. How not, when instead of trilobites that gnawed just so, it has to rely on molar-wielding masticators to spit out its pitlike young, and on constipated sharks? At first, the Golden Egg does what most desperate organisms do: what it used to do. It adjusts the hardness of sh.e.l.ls, the action of vents; it courts luck with better conditions for what used to work. With predictable failure. But in time, a mystery flowers: the Golden Egg finds its truth, a truth as unique and necessary as its fair foe, sweet scourge, and dearest dread, the lost trilobites. And not a moment too soon.

Pangea dissolves; ocean beds (again) become cloud-ringed peaks; this earth, not new, not old, thrums under monumental reptiles that mash their chicken tracks into the fossil record. Joy of joys, over conifer forests the maniraptors are aloft! Nine thousand species of birds descend from maniraptor nestlings, their beaks agape, shrilling. Music has evolved in the air. If I had been waiting, I would have been glad I did-though suddenly the sky is dust, ashes, roars, and sandpaper. Under sable clouds, in adamant gloom, the forests rot over the rotting dinosaurs, and for a weird historical moment, terrestrial topography is a Boolean ooze of phosph.o.r.escent domes, stalks, fungal shelves, funnels, and wrinkled gills. Then the ferns grow back as they did in my lifetime on charred Mount Saint Helens. For any age can interpose itself into the calendar of life, if circ.u.mstances permit. Any vista can return, any being can reawaken, more or less-the differences are what history is.

The Golden Egg survives the asteroid, alongside newcomers like ducks and regulars like crocodiles; outwardly it appears the same, but inwardly all is changed. Habitat, dry or wet, doesn't matter anymore. Like a sage, it lives by the grace of things beyond the present place and moment. Formerly filled with seawater, it is now filled with semi-heavy water, which, when hit by cosmic rays, emits a burst of cold fusion energy, turned by the Egg's superb bacteria into food. Dinner is served every century or so. Luckily, semi-heavy water, which prolongs the life of fruit flies, works wonders on the simpler organism, allowing it to wait for dinner, and for the withering away of its outer skin-if no animal a.s.sists-every forty thousand years. This period is not arbitrary. Like any egg, the Golden Egg needs to be rotated, and though no mother bird turns it with her beak, it has Mother Earth, completing a wobble around her axis every forty millennia. So the Golden Egg's lifecycle matches the tilt of a wandering star. Fortunate beast! It lives at the point of balance among powers: Sol, Earth, bacteria. With boundless energy, it is rich, yet the key to its wealth is balance. Humans can't use natural cold fusion because we demand much more energy-more than we can get without prodding nature into military-grade chain reactions. That's a problem of balance, not resources: the Golden Egg lives within its means. Yet despite my moralizing on its difference from us, there is a point of closeness, an overlap, where a hand may reach for a Golden Egg, after a last glance at human progress.

Fern forests shrivel, gra.s.slands spread, and over them skim horse-forms faster and faster because a squirrelly tree-leaper grew and grew and now charges their herds in the full cry and majesty of wolfhood. Over gra.s.s-foamed savannahs the years blur by until Equus, sole surviving horse, running like a tornado on a single, elongated toe, leaps clear into a field of icicles, leaving a glittering chain of hoofprints that do not melt, but meld into a frozen river a mile high in the air. The glacier's rock-hard arm rolls up the forests of Canada like a sleeve and goes to work, seizing North America by its scruff; and in four pulses, changes its grip. At my home address a giant ice talon, clawed with Canadian jaspers, rakes through the stone seabed in one long screech of a million years, leaving, at last, Niagara Falls hissing with rainbows. Solid roads of ice turn cheesy, withdrawing; the gravel spilled into potholes is left, marooned, in mounds, and would you look at this-buried in this mound, here, lies a bit of whelk sh.e.l.l, sc.r.a.ped, scored, and pierced by the agency you are using to hold this page, and I am using to reach, hesitant, toward the Golden Egg. For the polished sh.e.l.l's scratches fit together to make a picture. It depicts an animal, of course. An animal with p.r.i.c.ked ears, arched back, and two eyes in its profiled head, both facing you, because the hand doesn't copy what the eye sees, only the idea of what it sees. The idea of a Glacial Kame person was that if an animal had eyes, they were both meant to look at you.

"I see you," says the animal.

THAT WAS ALMOST YESTERDAY, and here I stand today . . . thinking about the sybil of c.u.mae. This prophetess was so old that she dwelt, like a bunch of raisins, in a jar. Her time was spent answering questions that must have been as crushingly repet.i.tious as a march. Will my ships come in? Will I have a child? Should I go to war? Can my sickness be cured? Once, a Roman in the long afternoon of his empire, given to introspection, asked her about herself. Sybil, he asked, what do you want? Her answer was, Death. My palm rests on the scabrous rock, bent fingers casting shadows that could be the bones of a fin, a paw, a wing . . . inside, the Golden Egg. Waiting to be cracked. Like the sibyl, it is full of the past and future at once. And like the sibyl, it knows what is enough.

A lull pa.s.ses through the insect chorus, except for one voice like the fluttering of an exposed watchspring. There are smells of dried gra.s.s and a swampy freshness from the pond, where slimed, peridot rocks crowd the roots of bowing rushes. Okay! Now I have drawn you the picture of an animal. It has no eyes for you, but you can look at it, while I'm off to check my birdhouses.

Rare Invisible Beasts

1.

Though I strive to explain the ways of invisible beasts, the Oormz resists all but the most superficial observation. This is poignant because I live with an Oormz and observe it daily. It merits description because of its vital connection to us despite its mysteriousness. My main reason for including the Oormz, though, is one that even scientists equipped with invincible theories, high-powered laboratories, and big data find themselves facing. One must accept that some projects are in the hands of a future generation.

The Oormz I HAVE AN OORMZ THAT LIVES in the corner of the window behind my desk. In summer, it's ashen blue, like sphagnum moss; in winter, the pale buff of dead leaves. Now, on a cold October day, it's browning around the edges, like the redbud leaves outside the window. It resembles a mohair wrap thrown over the curtain rod. In its brown patches, less fluffy than the blue, I observe the glint of tiny beadlike sensors that lie by the dozens under its nap. Each sensor caps a knotted cl.u.s.ter of the micro-fibers that make it possible for the Oormz to cling to smooth walls and ceilings, just as a gecko does. A gecko's pads don't work by suction. Instead, they're packed with fine, hairlike fibers that adhere to surfaces through sheer electricity. To break the bond, a gecko curls its toes; the Oormz curls its whole body, and then some.

I can call my Oormz by pursing my lips and making kissing sounds. Trained with saucers of sugar water, it now responds to my signal without a reward, like a dog. Of course, a dog acts from habit and affection-but no one knows what an Oormz feels, or why it does things, or what, precisely, it does. All we know is how they make us feel.

After a few air kisses, I watch it contract like a jelly-fish, its center coiling into a bluish misty rosette, while its edges ripple faster and faster into a buff halo. This activity is quite soundless, and no one knows precisely how the Oormz comes afloat over my head, spreading like oil on water, almost as if it were gliding along fault lines in the air. Then it covers my head-I brush it from my face-and drapes its faint cashmere over my shoulders, catching, incorrigibly, in my eyegla.s.s hinge. It smells like damp sawdust or an old willow-bark basket, though when it seems sick, I've known it to smell like stale vegetable oil. Too delicate to stroke (I might injure its sensors,) almost like a coating of bluish brown dust, it nevertheless has a strong, immediate effect. No sooner has it settled than the pressure wedged in my spine and shoulder joints streams away. My shoulders relax into the memory of a fast swim . . . oh, thirty years ago . . .

As I stood up from the lake, swimsuit dragging, my shoulders were bedecked in a crushing robe of gravity under which they squared, while my knees bent like golden hinges, and the new weight I bore only proved a young animal's strength. It comes back to me, the path through cold sand, cocoa-colored from pine needles, and I remember what sweetness there was in this old life of mine.

That's what an Oormz does. It's like a bandage between your animal past, sadly forgotten, and your present. I've known periods dominated by pettifogging human order and base human violence, when my Oormz has restored the memory of kneeling by the first spring I'd ever seen, my lips in the same water containing flowers and emerald moss. I wish everyone had a taste of that, and for that matter, I wish everybody had an Oormz.

What else can I say of this creature, with its nonexistent social life and mysterious biology-this merciful enigma, which now, in clear preference for the window corner, levitates and sidles toward it like a stratus cloud? A few papers quiver and flatten; the air's doing something-or-other. I know no more.

Except an old story. According to a speleological legend, deep under one of North America's large cavern systems lies an enormous chamber, a bubble in the earth's mantle, completely sealed. Inside it, like a woodchuck in a snug burrow, lives an Oormz that is miles long yet no thicker than an earlobe, suspended from the roof and walls. Because of its size, the monster is vulnerable to spreading rips and tears, so nature has given it a marvelous failsafe. Instead of having a heart, lungs, digestive tract, or other organs with specific functions, every one of the Oormz's vessels, from its gossamer capillaries to its yard-wide ducts, performs all its life functions in a complex sequence regulated by valves and pumps, from proton pumps and cell vacuoles to muscle valves-a sequence, mind you, that never repeats itself.

To imagine this, suppose you injected the Oormz with a dye that changed color whenever a vessel changed its function. Red dye would mean circulation; blue, respiration; green, endocrine; purple, immune; orange, sensory-and so on. Moments after your dye diffused through the immense mist of the Oormz, you would be standing with your head thrown back and your eyes trying to crawl out of it. The stained-gla.s.s windows of all the human cathedrals multiplied by factors of a thousand, set in motion like a kaleidoscope, without a single b.u.t.tress, arch, or mullion-without, in the stone heart of the earth, anything to interrupt the miles of animal rainbow-is an image suggesting what you would see.

The story has always struck me in its melancholy tone and fanciful humor. A creature of infinite variety, locked in an unchanging dungeon; a creature that comforts us with animal memories, whose nature we cannot fathom. From whom we can learn the worth of our time, never to be repeated.

2.

Can nonhumans feel empathy? The primatologist Frans de Waal adduces many examples. Chimpanzees comfort and pet their peers who have lost fights, and rhesus monkeys refuse to pull a chain that delivers food to them if it causes an electric shock to another rhesus monkey. Nor is empathy confined to primates. Rats liberate other rats from cages before helping themselves to chocolate-an impressive feat, as this chocolate-lover must admit. I'm intrigued by the topic because of the Hypnogator. Without the personal events that made me feel a twinge of empathy for this monstrous beast, I would never have solved the puzzle of its evolution. And I would never have understood the creature who revealed the presence of my successor, the next invisible-beast spotter of the twenty-first century.

The Hypnogator MY SISTER EVIE MET her unusual husband, Erik, the hero of this tale, when she was a graduate student in soil biology and he was a technical a.s.sistant in a psychology laboratory, a modest position he still holds. A naturalized US citizen, Erik was born in an obscure whaling station in Greenland. He's a big bruiser with a musclebound stoop, who peers with small, worried blue eyes from under shelving flaxen brows. His hands are like bunches of bleached plantains, and tough as nails. He is also s.h.a.ggy, covered in pale hair like some frost-coated figure out of Norse myth, as if he hadn't been born but was calved off the side of an ice floe. I've always thought there was something feral about him-a fluidity, his joints seem oiled-conjuring a creature neither man, animal, nor spirit, but all three: an apparition in the smokiest corner of a Viking hall, fists filled with icicles and thunderbolts. Despite this he is very sweet; the gentlest man I know, a devoted husband and father, and a vegetarian. His entrance into the family was somewhat b.u.mpy. I still remember my father grumbling to my mother something to the effect that his daughter "was not Fay Wray." My mother countered, in her soothing way, that gorillas made reliable, upstanding mates-not literally upstanding, but he knew what she meant. Then she called Dad "my funny honey monkey," which he didn't seem to appreciate. But we were all glad to have a man in the family after Dad was killed in a laboratory accident involving his work with high-energy particles. (I've promised not to discuss the details, but readers may get a sense of them at the link www.cyriak.co.uk/lhc/lhcwebcams.html.) Despite our father's misgivings, Evie's marriage transformed her from a thin, pallid, driven girl into a pink-cheeked, exuberantly driven matron, with a double chin the size of her engagement ring's satin cushion. And we discovered Erik's many virtues. He was handy with tools. He enjoyed music. He had a way of stopping sisterly spats by coming between us bodily, searching our faces, a great hand on each upset woman's shoulder; and while we might have resented this in someone else, Erik with his quiet glower seemed to recall us to reason. We felt better for his being among us. He read our favorite periodicals, too-Nature, Off de Waal Comix, the Journal of Irreproducible Results. And he collected a steady paycheck from the psych lab, where he was evidently prized, with a gift basket of tropical fruit at Christmas. He loved fruit.

Such was the family that encountered the Hypnogator.

Evie had invited me to join her, Erik, and their seven-year-old son, Leif, for a few days on a Georgia sea isle, where I would have the chance to see new animals-"visible animals," Evie underlined in that faintly condescending way of hers, as if she really wanted to sigh but had to speak aloud instead.

"You mean babysit while you're at your conference," I replied, deadpan. Bull's-eye!-her next remarks were full of respectful pleading. Leif was such a handful, he adored his Auntie Sophie, et cetera. I had the feeling that if we'd been gorillas, Evie would have been all over my fur, nit-picking in the best sense, then thrusting her infant into my trusty, hairy arms while she scampered away in search of the a.n.a.logue to scientific exchange. Maybe I wouldn't have gone, for all her verbal grooming, if my Oormz hadn't drifted down from its corner in the window, sifting over my ear, hand, cell phone, and mouth as if on cue. My Oormz is one of those creatures that are invisible to everyone but me; it looks a little like a smoky blue mohair wrap. Today, it smelled of stale vegetable oil and felt a little threadbare. Toto-as I call my Oormz-seemed to hint that we could both use a change of scene. So I agreed, and disembarked one sweltering July morning onto a soggy dock, with a tote bag, full of Toto, over my shoulder.

"Don't tickle," I muttered, as my invisible pet crept up my neck, and the young man unloading my overnight bag shot me a strange look. I smacked Toto and smiled. "I have this habit of talking to mosquitoes."

"Ma'am," he replied, "they don't listen." We trekked uphill. The place was absolutely strange, a throwback to some musty Zanclean, or Clarkforkian, age of the world. We reached a lawn of sand and tough gra.s.s infested with inchling cacti that caught in my sandals. The light was a brilliant gloom, coming down through a webwork of live oaks that loomed very tall and very low, tangling with one another's enormous, twisty branches, from which Spanish moss drizzled in an abandon that made me fearful for Toto-if it flew into one of those trees, I could never tell it apart from the ashen draperies. The shadows at our feet might have been copied from the set of Nos-feratu, though it was broad daylight, or sweating daylight, for moisture twinkled in the salt air. I was shown to a pleasant room full of ersatz antiques, which rea.s.sured and bored at once, a great place to nap. Toto swooped out of the bag and headed for the tufted bedspread where it wriggled contentedly, like a blue Persian cat without the cat att.i.tude or other landmarks. I went out to absorb the scenery before joining my relatives.

A sand trail ringed the island, furrowed by vehicle tires and overgrown by live oaks, moss swags, and palmettos; a jungle tunnel in which wet heat stagnated and my footsteps were m.u.f.fled. I followed a signpost to "The Beach," which led me to an abrupt vista of yawning, wind-carved dunes, without shade or animal movement, marching away through hostile, glittering air. The sea was a distant, mercury-colored smear, and the whole place breathed slow death. My fantasy of a quick dip shattered, almost audibly. I slogged with sinking spirits back to the inn, pa.s.sed through the giant live-oak grove, and right over my head, something screamed.

"Jesus!" I yelped, looking up at my nephew Leif, who lay on a limb, flapping his little arms. My hand rose to my lips-what if he fell?

"Raaaark! Raaark!" Leif screamed again, "I'm a velociraptor! Better look out! Auntie Sophie, look! Raaark!"

"Hey," I called. "Come down and give Auntie a kiss." He screeched again, a blond monkey in a sailor jersey and jeans, knees gripping the limb, blue eyes smoky with joy. Prehistoric raptors didn't listen to their aunts. I found Erik lying on the inn's porch swing, his s.h.a.ggy legs asprawl, reading journals and slowly transferring grapes from a red china bowl into his mouth. Pa.s.sersby gave him a hard stare when he turned the journal pages with his toes. From Erik, I gathered that Evie rode the island ferry to the mainland after breakfast and didn't return till dinnertime. That set our daily pattern. Erik supervised Leif during the early part of the day while I went hiking. He returned in the afternoon, when I brought my nephew back to my room for a bath and a nap. Then Erik climbed onto the naturalist's jeep for the daily tour, of which he never tired. The naturalist, Sam, a graying expert with an old salt's complexion and unhurried speech, liked Erik. Not so the other guests-at the beverage counter, they splattered iced tea on themselves when Erik's fist swept up sugar packets. They scuttled aside when he ambled through the gift shop, trying on hats. You'd have thought he was a wild animal rather than an easygoing family man. But Erik and Sam were friends, exchanging chuckles, grunts, glints, and meaningful nods. At dinner, Evie, tired from her ferry ride, told us about her day while supplying dialogue for Leif's tabletop skits starring his plastic dinosaurs, Steggy and Rex. For these dramatic parts, Evie doubled up her chin and spoke in a gruff low voice, giving her anecdotes a schizoid quality. The only catch in our arrangements was the stress on Toto. Before his nap, Leif liked to jump on my bed. Like a fledgling, he would soar and plunge, flapping his arms, screeching and singing, while the sensitive Oormz clung to the ceiling and shook.

THE MORNING OF MY DISCOVERY began with a noisy breakfast during which Steggy and Rex fought a battle beside Leif's gla.s.s of orange juice, and toppled it twice. While his parents mopped, I sneaked off into the crepitating palmettos. The trail smelled like arboreal body odor, a musk of indescribable antiquity that made my lungs strain to remember their gillhood. The path fell sharply to either side, rising opposite in a shallow bank, where I spotted a ragged hole. I thought it was an alligator hole. That was exciting. I toed down the steep side, hugging red pines, and rubbernecked as far as I dared. Sure enough, in the dark hole, over a gleam of water, lurked two silver, ghostly eyes, staring from behind a b.u.mp of nostrils. The rest of the gator was immersed, waiting. Judging from the hole's size, this was a smallish animal, maybe ten feet. I was too big a mouthful: otherwise, it would have submerged, hiding under the water that baited its trap, to conceal its shiny, giveaway eyes. It didn't think me worth catching. But those eyes, fixed on me, gave me chills-and resuming the path, I felt safer. That would have been all, if a rustle hadn't made me look back. An opossum had emerged from the palm scrub, and was trundling toward the gator hole. Marsupial tragedy and crocodilian lunch were imminent. The opossum, a female, waved her snout, sniffing water. Her face was affecting, with its white heart-shaped mask.

"Shoo!" I cried, violating Evie's rule of noninterference with other species. Too bad-I was a mammal chauvinist. "Scat!" She sat, glaring over her furry shoulder. Big ugly human. Then she dismissed me, waving her tight pink nose all around as if tracing fragrant signatures, her paws limp at chest height like a squirrel's. From her belly pouch hung, of all things, a sock ornamented with a turquoise pompon.

"Ha," I breathed. This was no ordinary opossum! She was a Poltergeist Possum, the invisible kind that pilfers human belongings. No wonder she wasn't afraid of humans. People don't kill Poltergeist Possums; they just go on looking for their lost socks or car keys. Now, as I stood on the tire-rutted path, suspicions began to stir. Down inside the dark hole, the alligator had not submerged. Its moonstone eyes were fixed . . . on the opossum? No, surely not. The gator couldn't see the invisible opossum. Only invisible beasts can see other invisible beasts, as a rule. It just happened to be looking in her direction . . . but so fixedly? I sat slowly on my haunches, suspense cracking in every joint. If those shiny optics vanished and the nostrils sank, it could mean that I had discovered an invisible alligator . . .

Then the unaccountable happened. The opossum gaped, her tooth-tips like ivory pencil points, and growled at the hole. That made no sense. Why was she growling? If threatened she ought to flee, or play dead. The shiny eyes blinked. Left, right, left, right . . . Why was the alligator blinking? Was I dreaming? I shook my head; my thoughts turned misty and scattered as I watched the opossum, with erratic growls, trailed by her ratty tail and turquoise pompon, lurch the rest of the way down the dirt track and-horrible-flail out of sight, under the rocking, glinting water's surface, with a muted splash. Another splash, a headless blob flung about, water again, an armor-ridged spine . . . Jesus Christ, I thought dimly, I have got to . . . I have got to . . . before I completed the thought, my feet had covered the mile back to the inn. When I tottered up the porch steps, I ran into the Erik and Sam, mulling over a digital camera, checking out its features. They treated me like an emergency.

"Drink," Sam declared, tearing the cap off a water bottle. Erik loomed very tall and grimaced, with clenched fists, in the direction I had come. His polo shirt swelled; his icy brows bristled. Whatever was out there had better leave his sister-in-law alone. Between the two of them, I felt much better. I said I'd seen a possum nabbed by a gator and asked Sam to have another look at the hole, which he checked every day and believed to be deserted. The two men zipped off in the jeep, only to return shrugging their shoulders. Any sign Sam knew of, of gators, was not there, but he promised to keep an eye on it; the word eye gave me chills.

Thus I proved that my alligator was invisible: it could see an invisible opossum, but humans could not see it. The next day, Leif grew bored with velociraptors.

It was inevitable.

Near the inn, on its cactus-infested lawn, lay a sunken cement enclosure that was once a fountain's basin, and all day, guests loitered there viewing a pair of young alligators with jagged smiles. They were four feet long and glowed like lava. At our second dinner together, in the evening, Evie told her little boy that the two alligators were living dinosaurs. We all laughed, watching the potato on the end of Leif's fork stop in his open mouth, right under his round, shining eyes.

"That's right," Evie said. "Eat your potato. So, you want Mommy to tell you about the gators?" Leif chewed, nodding so violently that Erik performed a calming pa.s.s over his son's head, and began transferring forkfuls of carrots into the little face hidden behind his great snowy hand. I watched our candlelit reflection in the French windows; Erik's unevenly slouched back was Mont Blanc, Evie's sharp, sunburnt face was an explorer's. The longer she talked, the more inferior I felt. I had no solar panel scales on my back, no special palate to open my mouth underwater and continue breathing through my nose above water, no moveable lungs to enhance maneuverability. No bone-digesting stomach full of gastroliths. I could run on two legs? Oh. Alligators ran thirty miles per hour on land. Alligators hydroplaned across water, too. Oh, and survived underwater without breathing for several hours by rerouting their circulation. What was I? What was humanity? Sam entered the dining room; the naturalist caught my eye in the window and made a gesture I liked, something between tipping a hat and showing a palmed card. I pushed back my chair and said good night, busy day tomorrow, not mentioning that my business was with an invisible alligator.

The next day, I hiked out eagerly, with questions. Did my gator hide its shiny eyes underwater even when its prey couldn't see it? In other words, did it behave like a visible alligator, or was its behavior modified by invisibility? Another morning's observation gave me the answer. My gator did not hide its eyes underwater. Like their visible cousins, invisible gators are stealth hunters, but evolution has given them a supreme advantage that makes most stealthy behaviors redundant. My gator submerged only when the prey was caught, to speed its death by drowning. Most of its prey would be visible-yesterday's Poltergeist Possum, poor thing, was exceptional. I still didn't understand why she hadn't fled the spot.

Now, I have to admit that although I try to love all creatures, my alligator was uphill work. Think of being slammed between those jaws, impaled on eighty teeth, water exploding into your lungs as you're ripped and shaken into b.l.o.o.d.y gobbets. Was this a beast, or a torture chamber with a mind? I must admit, shamefully, to some hatred. The hardest moment involved baby racc.o.o.ns. Young racc.o.o.ns don't desert their siblings. That's why racc.o.o.n roadkill often comes in twos: the second one has failed to abandon its dead brother or sister in pa.s.sing traffic. I should have been consoled by the knowledge that racc.o.o.ns will cheerfully eat baby alligators. But I wasn't.

The first little racc.o.o.n-a sooty-faced, ring-tailed puffball-at first scooted free of the water hole and yelled for help as only a racc.o.o.n can yell, like a siren being ground in a disposal. My hamstrings yanked and I might have lost my head (or other limbs) racing to its rescue, if a scaly, dripping, blunt snout hadn't shot out of the hole and whisked back underwater, as an infant yell etched itself through the insensate forest. Minutes died away. Then along came the second little racc.o.o.n, Bro or Sis, its potato-sized body vibrating over soft black fingers splayed in the dirt. It chattered like a manual alarm clock being wound, a percussive clucking purr. It searched, argued with itself, searched some more, looked at the sky, nodded back and forth before the gator hole, sniffed in the dirt, went round in a trembling circuit, and seemed at a loss. Meanwhile, two cold moonstones shone in the lair, without any expression a mammal could read. I dabbed at the tears behind my binoculars. To h.e.l.l with research: I threw stones and shouted to scare off the little racc.o.o.n, but as it retreated, the striped palmetto leaves gave away its position in the brush. It didn't go far. After I'd straightened up and painfully regained the path, aching in various body and soul parts, the little racc.o.o.n probably renewed its search. I didn't want to know.