March 31, 2008--Snowbirding: My Inner Fish (Concluded)

If you require further evidence about the truth of Evolution, come to Florida in March when the Spinner Sharks are migrating.

Last Tuesday, waiting for the appearance of inspiration in my writing room from which I have an unimpeded view of the Atlantic, they were on full display. Tracking north, following their food supply—in this case I learned, Spanish Mackerel--vast schools of these ancient predators thrashed in a feeding frenzy that roiled the otherwise flaccid ocean.

It was clear even to an uninformed observer why they have earned their common name, “Spinner” (more pictorial than the Latin, Carcharhinus Brevipinna), as they frequently leapt fully from the ocean and as if thrilled to leave their natural home if only for a moment to spin joyously glinting in sunlight. While overhead, ignoring them, circled scores of clamoring gulls and pelicans, both of which from great heights slammed headlong into the water to gather their share of whatever the ravenous Spinners had left behind.

Even before this riotous display I had been thinking about fish and even doing some reading about them. They are everywhere down here. Not just outside my window and not easy to ignore. There is their sport and commercial side. The Old Dixie Seafood Shop, for instance, just down the road is where fish boat captains bring their catch and the proprietors clean and display them in sparkling ice chests. There’s local Snapper and Red Mullet and Mahi Mahi. Swordfish from the Gulf Stream and whatever Tuna remains after the rest is snatched up by the Japanese fish buyers. The owner’s wife turns the occasional Wahoo into grillable steaks and whatever doesn’t get sold she transmutes into an incandescent salad flavored with just the right dash of celery-seed-suffused Old Bay. And then there are their specialties—Key-West style Conch Chowder and Smoked Marlin. They tell us that the Marlin spread is so popular that they sell 80 pounds of it a week. All from a tattered shack of a shop on an out-of-the-way stretch of, yes, the Old Dixie Highway.

But my reading takes me to very different places—to visit our deeper relationship to fish. Well beyond all the local surfcasting, sport fishing, and the resulting pleasures of the kitchen and table.

I had known from just a dollop of poorly-taught high school biology, when they still unfettered taught Evolution in public schools, that an even more fantastic transmutation than that which is at work at the Old Dixie Market with the Wahoo is the evidence that humans are no more than evolved fish. Fish that on a day, eons past, wallowed up onto land and of those that survived in this dramatically new environment they slowly passed along to us many of the physical characteristics that we too casually see to be unique to our own species.

For example, our boney head and large brain case with our sense organs fastened on are vestiges of our fish origins. And the fact that we have two ears, two nostrils, and two eyes set ideally apart, all essential to our survival, creativity, and progress, are also descended from fish, which also carry their sense organs in pairs.

The spines that allow us to walk upright so we can traverse the earth in giant bounding strides are modified versions of fishes’ spiny innards. All it takes to make that point is to observe what a waiter sets quickly aside after he at tableside filets your broiled Pompano. It takes hardly any imagination to see the relationship between a fish’s inner scaffolding and our endoskeleton.

Fins in humans became arms and legs; and our hinged jaw, tongue, and enameled teeth are as well gifts from the sea. Also fishes’ cranial nerves are not that far from our own. In fact, premeds who struggle to recognize, identify, and memorize their sequence begin by dissecting the skull or chondocrania of Dogfish Sharks. If they do so successfully, as I pathetically attempted, they discover descending first the Olfactory nerve, then the Optic, next the Oculomotor, after that the Trochlear, the Trigeminal . . . and finally the Vegus. All remarkably similar to what one would discover the first year in medical school. (Though I opted out before then and cannot offer direct testimony.)

And more recent studies of our distant cousins reveal that fish have many of the same social skills that make us, it appears, not-so-uniquely human. Most live in schools in large part so that they can be of help to each other, engaging routinely in acts of considerable, apparently generous fish-to-fish reciprocity.

African Cichlids typically live in groups of 10 or more and include a breeding pair and an assortment of helpers. Some of the workers defend their territory, others make sure the nests are cleaned, and still others do the hard work of oxygenating the breeding pair’s eggs. And remarkably, hear this human relatives, these so-called helper fish aren’t even biologically related to those they tend. They apparently do this thankless work so that they can benefit from the security against predators and the food supply made available by their collective behavior.

And fascinatingly some fish even experience menopause! To bad for them, and why did they need to pass this too along to us? I like my three-dimensional vision, but . . .

Enough reading! I needed to move this research out of my study and into the real biological world to see if what I had been learning in books could be tested and verified. And so, during the Spinner Shark migration season, unafraid, I took to the beach. With Rona not more than two steps behind. I suspected, to save me from myself.

In my mind it was like entering a scene from Steven Spielberg’s classic Jaws. I could almost hear that foreboding music thumping relentlessly above the muted surf. But unlike in Jaws the beach was preternaturally deserted. No one was standing ankle-deep in water, ominously looking out to sea in search of the fearsome Great White that was ravaging their community. Better the empty beach, I thought, to enable me undistracted to pursue my primordial explorations. Sharks I was seeking to be sure, but for what they could teach me or confirm what I had plucked from my reading about our ancestral relationship. This was not to be some cheap thrill from a Dime Novel or tawdry movie. No, mine was to be the work of a budding naturalist.

But wouldn’t you know that the first thing that caught my eye was a single footprint, the only one left behind by the wash of the lowering tide.

“Friday!” I cried out to the startled Rona. “Look,” I pointed in my delirium, “It’s Friday.”

“What are you talking about?” the gasping Rona managed to say. She was out of breath from having to trot to keep up with me. “It’s Thursday, silly. I know when we live this way it’s hard not to confuse the days of the week.”

“That’s not what I mean. I mean it’s who I mean. Don’t you see it’s just like Friday?” In my excitement the words came out twisted as I pointed again at the quickly eroding footprint.

She passed along that familiar smile she employed when she found herself in need of humoring me. Typically, like that day on the beach, when I was off on one of my fancies, which I had to admit were occurring more and more frequently during our unstructured days. And I quickly realized that this was another of those occasions and that I had allowed my literary imagination to distract me from my emerging interest in interspecies transmission.

Enough with Jaws and now enough with Robinson Crusoe! I was determined that from now on it would be strictly science and nothing but.

Friday would resolve itself again into the day before the weekend because the time I was needed to know more about would remain the Devonian, the geologic Period during the Paleozoic Era that lasted from about 415 to 360 million years ago when that first fish decided to try its luck on land and seed-bearing plants appeared upon and spread across the earth. This, I assured myself, was not going to be just another late afternoon 20th century AD walk on Delray’s beach.

And as if the sea and land could read my thoughts and in so doing generously chose to reveal some of their secrets, I saw right by the margin where the water met the sand edge signs of the kind of earth-shaping forces that carved our Grand Canyon, etched the shapes we see now across our vast western badlands, and put down those sedimentary deposits where the fossil record reveals the exoskeleton and story of those first amphibious creatures that are ultimately our parents. A microcosm of geological processes compressed in the brief time it takes for an exchange of tides.

“Look Rona,” I said, pointing again, “look at this.”

“What is it this time?” I sensed some exasperation. “What are you pointing at?”

“Right here. Right there. A miniature Grand Canyon.”

“You must be joking. We’re in Florida remember? Has the sun gotten to you already?”

“I’m not joking. Come here and take a look.” Hands on hips Rona sauntered slowly toward me. “You need to come quickly. The next surge of waves will wipe it away.”

“What kind of Grand Canyon is it that a little wavelet,” there was virtually no surf, “that a little swell of water can obliterate something that took eons [she was playing with me] to erode?”

“I’m not saying it’s a real canyon. Only that what took, what, 20 million years for Nature to achieve in Arizona is happening right here now in just a few hours!” Rona was staring skeptically at me rather than at what was in evidence right there at her feet. “I know you think I’m crazy,” she was nodding vigorously, “but I mean it. The same forces at work here are the ones that carved that wonder. Water in rapid motion, with sand grit suspended in it, is etching away at the subsurface just as the Colorado River did its thing out west.” I looked plaintively at her.

Rona knew these “insights” were important to me so she relented a bit. “Can we move on? It’s almost time for our afternoon drink and I thought we were out here looking for sharks. Not to imagine ourselves onto Defoe’s island, teach Friday English, or search for the origins of the western landscape.”

“I hear you, but indulge me one more thing. I’ll take a pass on the canyon-building stuff--though if you glance directly down on what’s right below the water here you’ll have to admit it looks remarkably like looking out on the Mohave from 40,000 feet.” Rona, with her arm folded across her chest, was now looking at me out of the corner of her eye. She checked the time on her watch in spite of the fact that she wasn’t wearing one. I knew I had only a few more minutes of her attention.

“I mean see all those shells that you like to rummage around in? Thousands, millions of them that keep getting deposited here with every tide. What do you think will happen to them in 10 million years? Limestone, that’s what. They’ll be turned into limestone and in it, as it compresses, paleontologists will 10 million years from now find the remains of these Gulls and Sand Pipers and Pelicans.”

“And me and you too,” Rona muttered, “if we don’t get a move on.”

In an attempt to acknowledge her sense of impatience, I pressed on and said, “But where are my sharks? The earth works business is fine, but I’m on a mission here.” I smiled, I’m searching for my earliest cousins.”

As if on cue, and to rescue me, right before us, not more than ten yards from the beach, another feeding frenzy exploded as dozens of Spinner Sharks descended upon a school of Spanish Mackerel that had become trapped between a series of shoals that were among the very ones I had been claiming were proto-canyons.

Both Rona and I instinctually jumped backwards to escape this thrashing about though no danger was evident. The sharks were much more interested in their Sashimi earlybird dinner than anything our flesh might offer.

“Look at that,” I cried, “Have you ever seen anything more basic, more natural, more primitive?”

“No comment,” Rona snorted. “It’s getting late.”

“Come on, admit it, this is exciting. Isn’t it?”

She finally smiled at me as the light lowered and blew me a kiss, “I do love you. You’re such a boy.” And added, “Yes, I’m excited. I love seeing animals in the wild. Even here in Condoland.”

As we were exchanging air kisses, the mackerel, in a hopeless attempt to escape, had worked their way closer to the beach. Those that had managed to avoid being consumed were hovering in just inches of water. Every time a wave retreated to the ocean, exposed to the air, they flopped desperately around on the sand, frantically trying to get back into the water and safety. Though there they would again have to contend with the sharks which continued to hover, waiting patiently in somewhat deeper water.

That is all but one of the sharks lurked out there to avoid the danger of finding themselves hopelessly beached. That one, we watched in rapt fascination, was working its way through the channels (my canyons) that had been scooped out by the relentless waves.

The mackerel shivered, huddling closer together as they observed their fate approaching. By now the water was so shallow that the shark’s dorsal fin, Jaws like, pierced the surface of the water. The movie music again started up in my head.

It moved in on the first cornered group and snapped up all of them as if it were vacuuming debris from the sea bottom. And then just as quickly it turned to the left where another small school was attempting to hide. The shark was so intent on completing its carnage that it ignored the underwater contours and thus found itself beached on a small ridge. By wiggling its body from side to side it managed to slide off and back into the safety of the relatively deeper water on one side of the mini-shoal.

But while it had been hung up half out of the water, as is so common at sea, the ocean’s surface had changed. Where it had been quiescent, it in that brief time it had become roiled by perhaps some subterranean force, and the newly-generated waves swept the unsuspecting shark right up onto the beach itself. And deposited it right at our feet.

Without a word to each other, in spite of the seeming danger, Rona and I did not take one step backwards. Science, evolution, geology be damned! Being there for this shark’s crisis took us over and riveted us to this perfect place to witness its, we were certain, final those. And it would be a lesson from Nature about the dangers of greed and overreaching. Why not to allow one’s emotions and instincts to rule.

As we stood there looking down at the shark in apparent agony, out in deeper water, its mates gave up their gorging and one by one begin to leap from the water, spinning in the air as if to signal that they were there, as understanding witnesses, and as a sort of collective biological beacon, glinting in the remaining sunlight, and by so doing generated enough activity and reflective light to guide their avaricious comrade back to their protective embrace.

But as we peered down at the shark, now fully washed onto the land, ignoring the leaping and spinning of the others, it looked up at us and we exchanged a knowing, inter-species glance of understanding: we recognized its plight as a fellow creature and it seemed to knowingly remind us of our ancestral connection.

Sharks are the earliest of sea creatures, I had read, to have paired pectoral and pelvic fins, and, using these, this particular shark, our ancestral progenitor, worked its way further up onto the strand. I wondered if it had become so disoriented by what had happened to it that it was placing itself at further risk by waddling landward on its protean legs.

While I thus pondered, it looked once more in my direction and, I think with a version of a shark wink, using its four fins again, turned its body toward the ocean and fish-waddled back to where it belonged.

But where indeed, I thought, did it belong? For surely some many millennia ago one of its ancestors made a very different choice and here we all are.

“It’s getting late,” Rona said, pulling me back from my reveries. “We didn’t have any lunch today and I’m getting hungry.”

I knew there was no possibility that I could continue to hold her here. So I said, “Me too.” In fact, I had had enough for one day and was ready for a reason to leave.

“You know the other night we went to that wonderful Greek restaurant. Taverna Kyma I think it’s called. I had a delicious Greek fish, a Lavraki, that they grill on a wood fire. I could go for that again. What about you? You had one too and liked it.”

With a final look out to the ocean where the school of Spinners had retreated, I said, “Kyma’s OK with me, but tonight I think I’ll have the lamb kabob.”