Sunday, December 28, 2008

What's In A Name? Part Deux

The pursuit begun so innocently in the previous post continues here. (If you've just stumbled onto this blog, I'd recommend reading the previous post to this one to help set the stage.)

What about those damned parentheses around Agassiz’s name in Carcharhinus egertoni (Agassiz 1843)? They tell me that Agassiz’s original name for this shark was changed by subsequent paleontologists.

A painfully inefficient exploration of the online versions of the Recherches sur les Poissons Fossiles, Agassiz’s multiple-volume treatise on fossil fishes (published from 1833 to 1843), turned up a single candidate for what he might have actually named this shark – Corax egertoni.

Could I trace this C. egertoni to my Carcharhinus egertoni? With some additional anguish and pawing through my library and the morass that is the web, I did. Way stations in the naming process included Galeocerdo egertoni, Prionodon egertoni, and Carcharhinus (Prionodon) egertoni.

Of course, after this whole process, I am in full agreement with the opening quotation in the latest International Code of Zoological Nomenclature (released by the International Commission on Zoological Nomenclature, the high court of taxonomic naming protocol and opinion -- link here). It quotes the preface to its first published code in 1961:

"Like all language, zoological nomenclature reflects the history of those who have produced it, and is the result of varying and conflicting practices. Some of our nomenclatural usage has been the result of ignorance, of vanity, obstinate insistence on following individual predilections, much, like that of language in general, of national customs, prides, and prejudices."

It’s an encouraging start, I think (listen to the sarcasm in my voice). Of course, the quotation continues in a vein much more likely to assuage scientific minds:

"Ordinary languages grow spontaneously in innumerable directions; but biological nomenclature has to be an exact tool that will convey a precise meaning for persons in all generations."

Now, we can only hope about the exactness. Frankly, what I wrestle with is not the exactness of the naming protocols, but rather the fluidity of the basic identification of specimens and ease with which long established names are conflated with others, substituted for others, or dropped in favor of those others. I am too new at this to know whether the experience of poor Carcharhinus egertoni is still the rule or the exception.

But, it only gets worse. I came upon a piece written in 2001 by Robert Purdy and others in volume III of the series published by the Smithsonian on the fossils of Lee Creek Mine (North Carolina) (link here). They describe the sharks, rays, and bony fishes found at Lee Creek. Their entries for Carcharhinus brachyurus and C. leucas brought me close to tears (okay, deep sighs may be more like it).

Though they could not inspect the actual “syntypes” of Corax egertoni (that is, the two individual specimens that Agassiz used to describe and name C. egertoni – possibly from Sir Philip Egerton himself), Purdy et al. felt able to reach conclusions about those type specimens from inspecting published plates of the teeth. One of the two type specimens, they concluded, is identical to teeth from another fossil shark, Carcharhinus brachyurus, and the other “compares favorably with a lateral tooth of Carcharhinus leucas.”

So, in just a few words, they eliminated C. egertoni as a distinct species and deprived Sir Philip Egerton of a bit of his immortality.

Though, I shouldn’t be too hasty. First, C. egertoni is still used by many and, without a doubt, if we wait long enough, someone else will rename this shark. And, if I were fully masochistic, I might take a new path in this hunt, perhaps up a mountain road in the Himalayas where I could see the Rusty-fronted Barwing, whose scientific name is Actinodura egertoni, one of a few extinct and extant animals with the egertoni species label. Hmmm . . . Sir Philip, are you there?

Saturday, December 27, 2008

What's In A Name? Part Un

What's in a name? that which we call a rose
By any other name would smell as sweet;
So Romeo would, were he not Romeo call'd,
Retain that dear perfection which he owes
Without that title.

William Shakespeare, Romeo and Juliet

So, what’s in a name? Nothing, says Juliet. Everything, say scientists, and sometimes proceed to make a hash of it.

Humans categorize, classify, and distinguish. We name things. Juliet would still have given an unnamed Romeo a name, just as we, if precluded from using the word “rose,” would not call it “that flower.” We are driven to label the objects, all of the objects, in our environment. To attempt to exert control over parts of an unpredictable world? To distinguish enemy from friend? To organize, and so make sense of the world? Yes.

I started out to write a post on scientific nomenclature in general since I spend so much time wrestling with the scientific names of fossils. I find myself tentatively saying a name out loud only to remember too late that the “ch” is a hard “k” sound, or that I have placed the accent on the wrong syllable. More important are those uncertainties born from names so similar for creatures so different. The genus Carcharias is not by any stretch of the imagination similar to the genus Carcharhinus. Still, there are those momentary synaptic pauses as my brain translates the name Carcharias to “Sand Tiger” sharks and Carcharhinus to “Requiem” (or “Gray”) sharks.

I focused on the shark that lost the tooth pictured below (lingual side of tooth on left and labial side on right) – the Carcharhinus egertoni (at least that's my take on it). Its teeth are typically triangular in shape with serrated crowns. Similarity among the teeth from the many species of Requiems poses a challenge to identifying specific species. Requiems are among the largest of the extant shark families, though the C. egertoni itself is extinct, having lived during the Miocene epoch.



Where I went astray was in deciding I needed to know something about the origins of that name and I began with the species label egertoni. As with so many fossil hunts, there are myriad choices to be made and not all of them work out.

My weapons for this hunt were the printed text and the web. The first fruits of the search were easy – the scientific name according to some sources is: Carcharhinus egertoni (Agassiz 1843). Given the protocol for citing the binominal names of species, the material in parentheses was a fair warning that this whole exploration was likely to get very messy. Had it been Carcharhinus egertoni Agassiz 1843, no parentheses, no problem – I would have known that Louis Agassiz, the great paleontologist, had described and named this shark in 1843, and that the name had stuck. Unfortunately, the parentheses tell me that whatever Agassiz named it in 1843 didn’t stick.

Still, Agassiz was a starting point. Amid the debris tossed up by my web searching was a name – Sir Philip Egerton, a name initially connected to Agassiz in Agassiz’s collected letters. Was this the name that became egertoni in homage? Who was Egerton and did it make sense for him to be the namesake?

Turns out that Egerton (1806-1881) was a passionate collector of fossil fishes and, seemingly, a man with a sense of humor (at least once in his life). He studied geology at Christ Church, Oxford, and spent the rest of his life in the pursuit and study of fossil fishes with a close friend, Lord Cole. Well, perhaps he did a little bit more than hunting fossils, since he also served in Parliament.

The Egerton-Cole combination is fascinating. Though they collected together for over five decades and shared what they found, they maintained separate collections, both of which were purchased by the British Museum after their deaths. As a 1904 history of the collections of the British Museum (link here) put it, they not only shared finds, they shared “the counterpart-halves of unique or valuable specimens.” I assume this means that, if, for instance, one or the other found a cast and a mold of a rare fossil, one would keep the cast, the other would keep the mold. That’s teamwork. (I trust they didn't actually split specimens.)

So, was Egerton immortalized by the species name? (And “immortalized” may not be the right word if it’s not obvious that the fish was named after him and nobody knows who he is. Wait, who would be the “namesake”? Turns out if I’m named after my father, I’m his namesake and he’s also mine. English is such an amusing language.)

At this juncture, I’m not positive that he’s the namesake, though I think it highly likely. Seems that in roughly 1830, Egerton and Cole were encouraged to explore fossil fishes by Agassiz himself – their lifelong obsession had its roots with the great man. They, in turn, provided Agassiz with many of the “type specimens” he used in his seminal work on fossil fishes, Recherches sur les Poissons Fossiles (1838-1844).

Yes, it’s highly likely that Sir Philip Egerton is the one.

For me, two aspects of Egerton’s life are deliciously ironic given my quest for the root of a species name. One of Egerton’s claims to fame is a satirical poem he wrote that ran in the May 18, 1861 edition of Punch. This piece cast a jaundiced eye on some of those scientists debating the consequences of Darwinian evolution for the uniqueness of humans, whether they could remain removed and separate from apes. He wrote from the perspective of, and signed the poem as “Gorilla, Zoological Gardens.” Anonymous! So much for names.

And then there’s his name itself. Turns out, as perhaps with many British with a title, there’s more to the name than at first meets the eye. Sir Philip Egerton was no exception. He was actually Sir Philip Malpas de Grey Egerton.

Wednesday, December 24, 2008

The Very Basic Equipment

Jasper Burns (Fossil Collecting in the Mid-Atlantic States) asserts that fossil hunting isn’t more popular because the basic equipment needs are so minimal that there’s no commercial push behind the activity. He may be wrong on the popularity – from the number of people I run into on my hunts and in online discussions, I think it’s plenty popular – but he’s right about the basic equipment needed to pursue the elusive fossil. Pretty much next to nothing. Bretton W. Kent (Fossil Sharks of the Chesapeake Bay Region) says that all that’s really needed to search for shark teeth on the beach is a pair of good boots, a container to store the treasures, and tissue paper for protecting the fragile finds. He and Burns do have a bit more extensive list of what would help in the search, particularly if the activity is not just cherry picking teeth on a beach. As the hunter gets further onto dry land, the list includes things like chisels and a hammer, glue (to patch those broken fossils together in the field), and band aids (to try and hold that cut finger together after shards of slate and wayward hammer blows inflict their damage).

Back to footwear for a moment. As one whose feet balk at being encased by most hiking boots out there, I put good footwear way up on the priority list. There’s a great homage to a recently deceased pair of hiking boots on the paleochick blog (link here). Most of my hunting is done on beaches and in streams so the primary boots on my list are waders and hip boots. My steel-toed boots are for the dry land adventures, particularly in mines, and finding a good pair that will allow me to live in them for 8, 12 hours, or more is a miracle. One key to success in the boot area are great socks.

Despite the notion that the equipment needs are minimal, I and others who hunt on beaches and in streams go to great lengths in acquiring or building wooden framed screens to sieve stream gravel, sticking screen on the end of potato rakes to drag through sand, wiring all manner of kitchen colanders to the end of long poles, ad nauseam. It’s a bit competitive. We comment, sometimes out loud, about the contraptions that others bring in search of fossils, asserting that this weird tool or that ungainly item is useless or priceless.

Still, after all of the acquiring of tools of the trade and the building of that apparatus that I think will result in great discoveries, I am increasingly convinced that the most essential, most fundamental piece of equipment necessary in this endeavor is the set of eyes I bring to it. And, to be precise, it’s not the eyes, it’s the eyes trained by the mental image of the fossilized objective of my search. This whole enterprise succeeds or fails almost entirely on insight – what I see on the margins of the image that my eyes transmit to my brain or what my eyes and brain do to the obscured fragment that is capturing the light. Is my mental image powerful enough to complete that fragment and guide my hands to the tooth whose distal root lobe is all that’s visible? Is that curving line that’s barely visible in the sand part of a water worn stone or the graceful swoop of a dolphin’s tympanic bulla (one of the ear bones – a thing of great beauty)? Am I really seeing what my screen holds? Whether I reach for and discover that fossil will depend upon how that mental image guides me.



(Of course, as with all things in life, I wont succeed if I’m in the wrong place. So, I add some geological maps to that quiver of fossil hunting arrows.)

Monday, December 22, 2008

We Always Assume Someone is Out to Screw Us

Yes, we always assume someone is out to screw us. Problem is, we’re often right about it. We just don’t know when we’re right and who’s responsible. We’re particularly inclined to put our faith in that person who warns us that someone else is out to get us. Rather, we should heed that little voice in our heads that says, “Beware of people who claim to have your best interests at heart.” (In my case, the little voice says, “Beware of steering committees.” It’s a long story. Maybe later.)

The situation is this. The U.S. Congress has several bills before it that seek to create a uniform policy governing the collecting of fossils on federal land. The title of the bills is the Paleontological Resources Preservation Act (H.R. 554 and S. 320 – also S. 3213 includes the text of S. 320 in it). Current policies on this do differ from federal agency to agency and, for a decade or so, the Congress has been working to bring this legislation to completion.

So, what’s the issue for folks like me? Well, there’s a buzz in amateur paleontological and fossil collecting circles that this legislation will screw us amateur collectors, prohibiting our collecting and imposing draconian penalties if we inadvertently violate its provisions.

Hey, I didn’t know that, under the current patchwork of policies, I could even collect fossils on federal lands!!

Don’t be ridiculous you gullible amateur collector. You can’t collect on federal lands, with one exception. On land under the administration of the Bureau of Land Management, you can collect invertebrate fossils, petrified wood, and other plant fossils. If, by chance, you’re in this for the money from selling fossils (a commercial fossil collector), then you’re really black listed and prohibited from collecting on any federal land.

To the point, the legislation under consideration specifically allows the Secretaries of the Interior and Agriculture (depends upon whose land is involved) to permit “casual collecting” of invertebrate and plant fossils. That’s amateurs.

So, who’s stirring up the concern of amateur fossil collectors about this legislation? As best I can figure it out, the commercial fossil collecting interests are largely behind it, trying to scare us in order to scuttle the legislation. Their fear is that this legislation would not only make it crystal clear that commercial fossil collecting on federal land is out, but establish penalties for violating that prohibition that are stiff enough to actually deter those collectors from despoiling federal land in their search for commercially valuable fossils. Unfortunately, my colleagues among amateur collectors are just as inclined to believe they’re being screwed as is anyone else, particularly if the purported villain is the federal government.

For once, it appears that the Congress is trying to protect federal land and keep some folks from using it for personal financial gain. It’s about time. I, for one, am in favor of this legislation. Doesn’t affect me and I think we need a uniform policy. So, who’s out to screw us? Believe me, somebody is. Well, first, the “us” in this case isn’t just amateur fossil collectors, it’s the U.S. public who are the "screwees". And the “screwers”? Well, it’s not the feds. I’ve drawn my own conclusion.

Sunday, December 21, 2008

Suspension of Disbelief


Hiking down the root-punctuated path, a faint corridor through a sprawling woods of maples, tulip poplars, and oaks, it is easy to believe that I am being stalked. The feeling is vivid, real. The product of too much television, too many movies. A switch to "subjective camera" (a la the movie Lady in the Lake) and it's all being seen through the eyes of someone breathing heavily and watching through bushes as our intrepid fossil hunter stumbles over a tree root. Yes, this is all too easily believed, and my heart races a bit until a deep breath calms my run-away imagination. I actually mumble out loud, "This is Deliverance." What gives? Here I am citing a movie I've never seen, but this metaphor probably captures for a majority of Americans the fear of being stalked in the wilderness.

How easily we believe some things (at least, react as if they might be real) and how difficult we find it to believe others. For instance, had I been in this place and transported 60 million years into the past, I would be underwater, in a warm sea, drowning and probably being eyed by a mackerel shark, an Otodus obliquus. Now, that proves a challenge to my ability to suspend disbelief. My eyes don't lie. I am walking on solid ground where trees grow 40 feet or more into the sky, blue jays mark my passage, and myriad squirrels set the underbrush crackling. This could never have been under water. Yet, it is true that in the mid to late Paleocene, the Salisbury Embayment, a basin of the Atlantic Ocean, covered this part of the Potomac shore line. These were waters crowded with bony fish and dominated by predator sharks. There were no mammals, no whales, no dolphins, . . . yet. (Well, except for me as I complete the process of drowning.)

As I reach the shoreline and begin my trek along the beach in search of the fossilized remains of creatures that swam these waters so long ago, I find it becomes easier to suspend my disbelief and glimpse that world long dead. Dead, well, perhaps not. The interaction I begin to have with that world slowly comes to seem all too real, all too alive. That world reaches out, pokes through the veils of time, telling me and anyone else who cares to be open to it, that multitudes of lives were lived and lost right where I stand, above me, around me, below me. Of course, it becomes so much easier when the fossils begin to appear. It takes a moment for my eye to acquire the "search image" that makes the teeth emerge, as with this sand tiger (a Carcharias sp. -- the "sp." indicates that I have been unable to identify, or too lazy to identify, the species for this tooth).

When I scan the cliff side in front of me I see the layers of sediment that have been laid down over millions of years, as the Salisbury Embayment ebbed and flowed over this area. The fossils littering the beach and embedded in the cliff side are coming from the Aquia Formation. And in those layers, fossils of invertebrates -- gastropods, snail-like creatures -- stand out.

Over time, I am finding it easier to believe what this world was like in the distant past. It is a developing understanding that uses my imagination as a tool, a way to enhance my ability to see that world. Still, as I walk through the woods alone . . . .

Saturday, December 20, 2008

Feeling Your Age

I hadn’t run in a week because of a vicious head cold which left me hacking, blowing, and feeling generally wrung out. So, I set out on a 2 ½ mile run despite still suffering, determined to turn a corner on this illness and reassert some control over my life. It’s an illusion, I know, and I know that because I’m feeling my age. I am no longer in that period of life where immortality is a given, where you believe things will only get better and you with them. “I wish I didn’t know now what I didn’t know then.”

I wonder about the creatures whose remains I find as fossils – did they understand what it meant to feel their age? Not their geological age, we are the only living creatures ever to be aware of that. No, I wonder what, if anything, crossed an aging Dunkleosteus’ mind as the snap of scissor-like plates in its armor-encased mouth failed to slice its intended prey in the bloody Devonian seas, or a veteran Carcharocles megalodon’s mind when a river dolphin danced away from the 6 inch tall teeth of this mammoth shark, or any of nature’s predators when, what used to come easily, now eludes them? I suspect that, if any animal other than we humans ever felt a chill about the meaning of this experience in the latter portion of a life, it must be the predators. Prey animals don’t live long enough to experience it, and, besides, fear is their watchword anyway.


Notes

The Dunkleosteus was a 20-foot long armored monster that cruised the ocean in the Devonian period, some 360 million years ago. This fish was truly a terrible and ugly thing. The megalodon, the largest predator to ever live, stretched some 50 feet and weighed upwards of 50 tons. This shark lived much more recently, beginning during latter portions of the Miocene epoch (perhaps as early as 30 million years ago) and surviving through the Pliocene epoch, at least.

Check out the brief facts put together by the BBC on these and other sea monsters.The Dunkleosteus piece is at: http://www.bbc.co.uk/science/seamonsters/factfiles/dunkleosteus.shtml
The megalodon one is at:
http://www.bbc.co.uk/science/seamonsters/factfiles/megalodon.shtml
Be sure to look at the very short videos for each animal. The computer animation is sufficiently crude to make it all seem real, particularly if you view them full screen.

A good, informal treatment of the megalodon is Megalodon: Hunting the Hunter by Mark Renz. You can read a bit of the book on Google Books: http://books.google.com/books?id=cMRe5GmDXmUC&printsec=frontcover&dq=mark+renz#PPP1,M1"

Why Do This?

Why initiate this blog? Because as I’ve delved deeper into paleontology the feeling has become stronger that there’s some deeper meaning or meanings to my adventures in this arena. I don’t think I can tease them out without the discipline of putting words to “paper.” And I don’t know whether they are deeper insights into the discipline of paleontology or life, or both. I think knowing there is an audience (well, at least, potentially an audience) will add a bit of discipline and spice to it. I am an amateur, for better or worse, at all of this.

At the heart is my fascination with things ancient, particularly those that predate history by millions of years. There’s the tantalizing glimpse I have of life before there was human consciousness that tried to make sense of it. The veil that shields this prehistoric life from our awareness is an impenetrable gauze, we can never be fully there. Yet the veil is so sheer in places that images of those other sanity-challenging times can come through to shock us.

The bitter sweet satisfaction and frustration I feel as I struggle to apply the processes of this science to what I find in the field mirror those I experience when I try to make sense of my quotidian journey through life. Clearly, the disciplines of the mind are not enough for either endeavor. This is an exploration of the necessary blending of science and art, of mind and heart. The essence of striking a balance, I suppose.

I am also in pursuit of the absurdity of this experience, those aspects that make absolutely no sense or are unbearable unless one has a sense of humor. Paleontology without laughter is an enterprise I want no part of, I could have no part of. There is too much that is painful in this that is tolerable only if I cultivate my sense of the ridiculous. How else would I be willing or able to come back and do this again after spending six hours shoveling gravel into a screen, while standing knee deep in a stream in the dead of winter, (and here’s the cruelest cut) without finding a recognizable fossil? How else would I refrain from going home and throwing my “treasures” into my garden when I experience the rush of finding a 60 million year old shark tooth of surpassing beauty only to fall into despair when I realize that most of its root has long since gone missing? Or when I think my day-long exploration of a site has gone well only to miss the truly exceptional specimen that a late comer unerringly spies upon first venturing out? That’s when I have to laugh at it all, every aspect of it all. Though, I must admit, there are times when the laughter fails.
 
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