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Creek Running North

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December 27, 2004

Crinoids

One from the archives. I wrote it about 10 years ago.

Crinoids

Over the years clay settled, grain by grain, to the seafloor. It must have been an exceptionally calm sea, with little current to stir the bottom, as the layers of shale that formed from the clay are thin and even. You can trace those layers for miles along the cut banks of the creek, only a few degrees off plumb: a band that is at the water line underneath the Bullis Road bridge rises slowly as you head west and downstream, to vanish, eventually, into the humus of the silver maple forest at Chair Factory Road. One band in particular is thicker and harder than its neighbors; evidence of some distant catastrophe, a flood or a volcanic eruption or something else, that caused a much larger than usual quantity of sediment to be deposited, all at once, on the bottom of this Paleozoic sea covering what would, for a small fragment of time unimaginably far in the future, be called Western New York.

It is that band that my brother and I trace today. Trudging along the bank, losing the occasional shoe in gray mud, we look for an easy route to the harder rock now twenty feet above our heads. We find it at a seep in the east bank, brimming with mosquitoes, where water has cut a purchase into the steep outcrop. The slope is still well above the angle of repose. We slide a foot downwards for every two climbed until the bank levels out, just beneath the hard rock layer we've been chasing. The water, flowing in a trickle underground, can't penetrate this layer; it is forced to the surface, to spill over and cut a hollow in the softer shale beneath. Craig reaches a muddy hand into the hollow, pulling out a slab run through with the fossilized remains of crinoids.

The creeks here on the east edge of Erie County were the place where I grew up. Outside of school hours I was usually in the creek back of the woods. It was a rich landscape, and we kids had our own local folklore based on the terrain. There was Dead Man's Cliff, a fifty-foot escarpment on Mr. Bontrager's land; while risky to climb, you would have needed to plan carefully to actually die there. Half a mile upstream from the Cliff, there was The Hollow Tree, where, rumor had it, someone had once found "an old guy, just sitting inside, smoking a cigarette." The creek was full of pools, and the pools were full of dragonflies, which would, of course, sew your eyes shut, so that you'd fall into the water where the minnows would promptly eat all your skin. Always the skeptic, I had to offer my skin to some minnows the very next time I was alone on the creek. The outcome of this incredibly risky experiment was disappointingly anti-climactic.

Emboldened by the fishes' failure to decorticate my leg, I followed one one day as it escaped, flapping on its side, up the slack, sun-warmed creek. The water was shallow, running blood-warm as it rode over the glass-smooth shale, slippery with algae. Twenty yards upstream lay a small riffle, the pool beneath partly sheltered by a small ledge of harder rock, under which the fish darted. I reached slowly into the water, rippling the reflected sun and maple leaf canopy, and felt under the ledge. The fish tickled the side of my hand, swimming into my palm. I pulled it out of the water.

It was no minnow at all, but a tiny catfish, three inches long, olive drab and surprisingly tame. That tameness was its undoing, for it left the creek that day in my cupped hands to be carried a half-mile to my house, there to live out its truncated life in a wide-mouthed gallon jar. I no longer remember what, or if, I fed it; I do remember the increasing green cast to the water in the jar, and my mother's obvious relief when that water, along with the still and floating catfish, were poured out. The tenacity of that fish, first at surviving a hot twenty minutes clamped in a ten-year-old boy's hands, then at living two months in chlorinated water on the coffee table, still impresses me.

The catfish was only the first of many interesting things brought home from the creek. There was the garter snake found at the foot of Dead Man's Cliff, which went home with me contentedly enough, biting me only once, and from there off to captivity in a friend's vivarium, to be fed to satiety on goldfish and pink mice, and which I never saw again.

There was the day we found the red-winged blackbird nest. Eight feet up in the branches above the creek, I stole the eggs as mama red wing screamed protest a few feet above my head. Faint peeping came from inside the shells, then from out the shells as the chicks saw the light of day, far too early, at the hands of dispassionate boys. To this day, when I see that flash of red swaying in the breeze, black bird perched on streamside reed, when I hear that dissonant cry, I think back to the day of the massacre of the redwing chicks, and feel shame.

But most of what I took from the creek brings me no sense of shame a quarter century hence. The shale over which the creek flowed was soft, peeling away in thin sheets perfect for skimming over the surface of the small pools. That is what my father and I were doing one weekend morning, enjoying sun-filled conversation on no particular topic, picking up those gray stones and flinging them. One stone felt odd to the touch. I took a closer look. It was not at all flat, but sculpted into graceful and symmetrical curves, unlike anything I'd ever seen before. I showed it to my father. The rest of the weekend was spent not flinging stones, but turning them over and stuffing certain of them into our pockets.

I knew what I'd found had to be a fossil. Once home, after a quick look through the Golden Guide, I also knew it to be a brachiopod, probably of genus Spirifer, possibly Mucrospirifer. The words were hard to pronounce, and I had no idea what they meant. But I did know that the creek was suddenly full of treasures. I had a few friends in the neighborhood, and I tried to infect them with my new-found passion for the Cayuga Creek Devonian fauna, but though they gamely followed me on a couple of midday fossil hunts, none of them evinced more than a passing interest in animals dead hundreds of millions of years.

Crinoids, also called sea lilies, lived in the shallow seas of the Devonian Period, about 350 million years ago. Like many things commonly called lilies, they weren't: they were animals, invertebrates related to present-day feather stars. For much of their life they were sessile: they stayed in one place, rooted to the sea floor by way of a plant-like trunk composed of cylindrical sections placed end to end. It is these sections the modern-day crinoid collector is most likely to find. Atop the trunks was an anemone-like tuft of arms that actively gathered food from the detritus suspended in the water. The crinoids whose remains Craig pried from the cliff face may have felt some ambivalence about the thick flood of sediment that entombed them, sealing them off from the light of day from the Devonian until just this second. A little at a time, the detritus might have kept them well fed.

It was a healthy stand of crinoid "forest" that fell prey to calamity here: we find dozens, hundreds of individuals immediately under every section of the thick slab we can examine, up and down the creek. The seasonal cycles of freeze and thaw have pried more crinoids from this cliff than could ever be picked up; many of the fallen disks have crumbled into clay. Exposed to the elements for the first time in a third of a billion years, most succumb within a season or two to the strain of sun, the impact of falling shale. Some are washed downstream to be dissolved in the water of the creek.

Swatting mosquitos, I think of fossils unfound. Smothered in the middle of the Paleozoic, the crinoid stems rotted, their shapes preserved in tropical clay. The mold hardened and muddy water seeped in, slip-casting perfect replicas of the echinoderms' stalks. Then the pressure built. Layer upon layer of sediment was laid down on the seafloor, interring the remains in a tomb hundreds, perhaps thousands of feet deep. They lay that way for an inconceivable length of time.

I can imagine the pace at which a crinoid spent its life. Light and dark, high and low tide, summer and winter are rhythms I have experienced. These rhythms ruled the crinoids as well, though the Devonian Earth's rotation may have been a bit faster, making the day a bit shorter. But the span of time that has passed since the crinoids were buried is utterly beyond my comprehension. This time scale, which some have poetically called "deep time," cannot be directly apprehended except through the use of metaphor.

It is fairly commonplace for paleontologists, seeking to convey the immense stretches of time with which they wrestle, to compress the history of life on earth into one year: a hundred years equal about one second. Life appears on New Year's Day. For three-quarters of the year the Earth is ruled by enucleate cells, similar to bacteria. The oldest known fossils of multicellular organisms show up on October 12. The first crinoids, along with brachiopods and trilobites, evolve in the first week of November. The crinoids in Buffalo and Cayuga Creeks die on Thanksgiving Day, after too large a banquet of silt. December sixth brings the Age of Dinosaurs, its eponymous creatures going extinct on the night before Christmas. Humans evolve around nine p.m. on the thirty-first, and recorded history commences less than a minute before midnight.

It's an instructive tool, this metaphor, but it still doesn't convey the incredible scale of the change that has occurred since the crinoid forest was smothered. The crinoids' species, then their genera, then most of their family went extinct. The sea they lived in dried up. The mosses and ferns that had been the crinoids' contemporaries evolved into seed ferns, then into cycads, ginkgoes and conifers. Fish crawled out of the water to beget amphibians, which begat reptiles, which begat mammals and dinosaurs. Life on earth was nearly wiped out three, four, five times. Most of the species alive when the crinoids were buried were extinct; most of the species that had evolved afterwards had gone extinct as well. The continents coasted around on currents of mantle, bumping into one another and rebounding, until by fluke a few of them circled a shallow ocean near the northern pole. Warm water from the southern oceans blocked, the polar sea cooled. Then, in a dozen or more rapid and destructive pulses, starting at 8:00 pm New Year's Eve by the deep calendar, tongues of mile-thick ice shot out across the land, wiping out the forests of flowering trees that had evolved in the time of the dinosaurs, and scraping down the surface of the land like a continent-sized rasp file.

I stand here, searching the rubble of the bank, between two of the glacial pulses. The next pulse, a century or ten millennia from now, will grind all history of this crinoid forest into oblivion. I find a stone that seems the right shape to be a crinoid stem, but the water of the creek has erased the features. I cannot be sure this is not just a cylindrical rock. I feel, turning it over in my hand, as if an echo of a recording of a death cry has faded just before it reached my ears. All I hear is noise that might be a voice. The story of this section of crinoid stem, if it was in fact a crinoid stem, is gone forever. Its long journey through the history of life on earth has been wasted.

Most of the free days we had that summer long ago were spent hunting fossils. Craig, about to enter school, was just old enough that my mother would entrust him to my care. We'd walk down to the creek and start turning over the rocks, finding many more fossils than we brought home. Many had been partially destroyed; we were interested only in complete specimens, or at least good-sized chunks. We'd find hundreds of partial brachiopods, their valves prised apart by some force long-forgotten, whether Devonian predator or Holocene ice crystal. Many of the broken shells looked laminated, a flaky translucent layer coating their insides. Some of the fossils were left behind due to their large size, such as an unidentified cone about a foot long and four inches wide, embedded in a large intact slab, and beyond our ability to carry. And some fossils, intact and portable, were just left behind, devalued by the abundance of similar relics in our pockets and in boxes at home.

We found Eutaxocrinus, the most common crinoid in Western New York. There were Spirifer and Mucrospirifer, and a half dozen other brachiopod genera. Ptilodictya, a bryozoan, with its narrow dendritic stems and pitted surface, was there in abundance. We found cubic feet of Siphonophrentis specimens; a conical coral which we familiarly called "sharks' teeth." There were worm borings and colonial corals and things that might have been colonial corals but had been encrusted with crystal over millions of years, preventing identification. Sometimes we'd find Chaetetes, an animal some paleontologists place in the sponges, while others assign it to the tabulate corals. And on an especially good day we'd come upon a trilobite, an animal already hastening to extinction in our part of the Devonian. Most were the typical flat, shed skins common in rock shops; one, the prize of all prizes, was curled up like a pillbug, evidently defending itself against a predator when it met its death. It is the one object I truly regret no longer owning.

Summer waned, school loomed on the horizon. One afternoon I grabbed my new used bike and headed down toward the banks of the creek to do a little collecting. The bike, handed down by a second cousin, was a few inches too large for me; a late-summer crack in the dry clay of the path caught the front tire and I, unable to dismount, regained consciousness staring at my horribly distorted left arm. I had landed on it; the momentum I had gained on the bike had sheared through my humerus just above the elbow. My sister, who had been playing a hundred yards away, ran screaming for a neighbor. The doctors tried to set the break, but failed, and I spent a month in traction, a pin drilled through my bone with ten pound weights attached. By the time I was recovered enough to clamber up slippery shale banks, two operations and five years later, we had moved into the city.

Craig trundles down the mosquito bank and hands me a few more pieces. I walk to the shore of the creek and place them in the mesh potato bag with the rest of the day's finds. A plume of gray flows downstream from the bag. There are things your mind forgets, but other parts remember; the smell of timothy trodden underfoot, the feel of a creek thick with warm algae around your ankles, the smooth taste of Devonian seafloor. These things have worn me down into the shape I am today, and I feel a palpable snap as mold fits cast again, almost as if I were a gate being pushed back into place, the latch on the other side falling into its slot. The fence holds me snug. I'm home.

But that's not quite it. This is my home as a ten-year-old. I'm no longer ten.

I had intended on this visit to go back to that stretch of Cayuga Creek upstream from Two Rod Road, to walk, and pick up the occasional stone, and perhaps to find a hollow tree and sit in it, just smoking a cigarette. But the Army Corps of Engineers had gotten there first; a flood control project now lines the banks. Tons of riprap entomb the memories of childhood in a sepulchre as dark as that any fossilized crinoid forest knows. Ledges that might have sheltered the twenty times-removed grandchildren of my catfish now lay bladed and hemmed in by exotic rock, trucked in from some distant place and inappropriate time.
It's contrary to the lessons of deep time, but I feel sometimes as if all events in the past are equally distant. I can no more regain my tenth summer than I can bring the crinoid in my hand back to life. I examine it closely. It's just an average section of Eutaxocrinus, a half inch long and wide, delicate tracings around the barrel of the stem. I found many stems indistinguishable from this one as a child. Its cousins snuggled up to the roots of the trees we climbed, fed my father's garden with their minerals, held up the ground on which we walked. My father's leaky basement floor sits not twenty feet above part of the forest in which this crinoid lived. There's not a single thing that could express to me more powerfully the nature of the place I used to live, from its impossibly distant past, to my impossibly distant past, to our mutual present. I should keep this one as a talisman, to take back to my apartment in Oakland, so that I can hold it and remember these thoughts.

Craig heads for the road, carrying the rock bag and his shoes, his pants soaking the warm water up to his shins as he walks up the center of the creek. The water feels good as it leaks through my boots. I take them off, feeling the slick algae glide downstream over my toes. I'd forgotten how hard it is to stay upright on this slippery shale, a balancing act that once occupied the better portion of my life. Time to do it again, to walk with my brother up the middle of a creek for the first time in twenty years. Absently, I drop the crinoid stem on the bank, then turn and follow.

Posted by Chris Clarke at December 27, 2004 01:12 AM TrackBack URL for this entry:
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Fossil Hunting along Buffalo Creek
Excerpt: One of the good things about growing up in Western New York was summer says spent in creek beds searching for brachiopods, corals, sponges, crinoids and the best prize of all, trilobites. The trilobite was the ultimate prize. Even now I subscribe to Ya...
Weblog: life in Buffalo...
Tracked: February 17, 2005 02:38 AM
decorative line of bighorn petroglyphs


decorative line of bighorn petroglyphs

Comments

...yeah...what she said. only thing is i LIKE reading you online everyday TOO!

Posted by: Anne at December 28, 2004 02:55 PM
decorative line of bighorn petroglyphs