Saturday, November 28, 2009

Take Heart, Rachael

Life’s not fair. And, in particular, a fossil hunt’s not fair. That’s a lesson a fossil hunter learns quickly. But, that’s not the central message of this posting. I think there’s yet another lesson that a fossil hunter learns that may offer some measure of consolation. More about that in a moment.

Local newspapers and TV stations recently ran a story about a find at the newly opened Dinosaur Park in Prince George’s County, Maryland. Yes, there are dinosaur fossils to be found in the urbanized Baltimore-Washington corridor. The 7 ½ acre county park provides an opportunity twice a month for amateur collectors to try their luck at turning up a Cretaceous fossil, perhaps from a dinosaur. Saturday, a week ago, a small piece of fossilized bone, tentatively identified as a dinosaur vertebra, came to light, found by a young girl. The fossil triggered a great deal of excitement and was turned over to the Smithsonian for identification and further analysis.

Here’s where the life lessons come in. Am I taking liberties with the known facts in the account that follows? Of course. But then the truth I’m looking for is behind the events and details reported in the press. And the best way I know how to do that is to project on to it my feelings and experiences as someone who has hunted for fossils, has children, and, in particular, has siblings.

The story goes like this, punctuated with my annotation, including a bit of reconstructed backstory. A family of four from a neighboring state comes over to take part in the last hunt of the month. The outing, according to the press, sounds like a piece of healthy and constructive parenting, but, I suspect there was a lot of pressure (begging and whining . . . maybe) brought to bear to make this trip a reality by Rachael, the younger daughter in the family, a child overwhelmingly infected with the dinosaur fossil bug, whose grandest dream, according to her mom, is to go on a fossil hunt in South Dakota. Her older sister, 9-year-old Gabrielle, comes along, perhaps reluctantly (I know as a child I would have protested going on a trip if it were something very special for one of my siblings). In my reconstruction, the final conversation in the car as the family caught sight of the park goes something like this:

Younger sister Rachael: “This is so cool. I can’t wait. This whole place was a swamp maybe 100 million years ago, with dinosaurs and everything.”

Older sister Gabrielle: “Whatever.”

A half later, Gabrielle finds the dinosaur vertebrae that causes all hell to break loose. Well, that’s what it must have seemed like to Rachael.

The family is interviewed by the press. The local experts at the park are ecstatic, gushing over the marvelous find by this “little girl,” thrilled at the press coverage for the park. Gabrielle has her picture taken which runs in the Baltimore Sun along with an article. The Washington Post covers her find as well, as do other news outlets. Clearly, she thoroughly enjoys her brush with fame. To add salt to Rachael’s wound, in her picture in the Sun, Gabrielle’s holding a stuffed toy, no, not a dinosaur – a stuffed walrus. As for Rachael? One reporter notes that Rachael “kind of wished she’d found the fossil herself.” A bit of understatement if I know fossil hunting and sibling rivalry. (Girl Hits Pay Dirt on a Fossil Hunt with Her Family, by Megan Greenwell, Washington Post, November 25, 2009 ; New Dinosaur Park Yields Fossil for 9-Year-Old Girl, by Frank D. Roylance, Baltimore Sun, November 24, 2009)

Take heart, Rachael. I know you’d already learned that life’s not fair – having a sibling ensured that. You’ve now learned that fossil hunting’s not fair, either. Your enthusiasm, dedication, knowledge were no guarantee of good things happening (not in this instance, but, trust me, they will pay off in the future). The whole process is too dependent on contingency, historical accidents. Your sister’s finding of that fossil is the end result of an incredible chain of events that stretches further back in time than even the moment 100 million years ago that the dinosaur sank into the mud, dead. Change one of those events and maybe the fossil’s 7 inches to the right and Gabrielle misses it or, go back even farther and tweak an initial condition and there aren’t even dinosaurs, at least as we know them, to become fossilized. Now, that would be a shame.

The debate over contingency in the paleontological world might provide some insight for you, Rachael. I'm sure you understand that we're applying it at a much more micro level than the paleontologists have.

Contingency became paleontologist Stephen Jay Gould’s watchword for life’s evolutionary history. As he wrote in Wonderful Life: the Burgess Shale and the Nature of History (1989),
The modern order was not guaranteed by basic laws (natural selection, mechanical superiority in anatomical design), or even by lower-level generalities of ecology or evolutionary theory. The modern order is largely a product of contingency. (p. 288)

Based on his interpretation of the Burgess Shale and the many anatomical designs he saw arise there only to be decimated, he came away with
amazement . . . at the fact that humans ever evolved at all. . . . Replay the tape a million times from a Burgess beginning, and I doubt that anything like Homo sapiens would ever evolve again. It is, indeed, a wonderful life. (p. 289)

Too much of the process was, in his view, historically contingent to ever replay in the same way.

Others, such as Simon Conway Morris, have rejected the extreme nature of this view, arguing that there are, in fact, a constrained number of successful evolutionary options. As a result, Conway Morris wrote, “the evolutionary routes are many, but the destinations are limited.” (Life’s Solution: Inevitable Humans in a Lonely Universe, 2003, p. 145). In the same volume, Conway Morris repeats this theme, but adds an important coda:
Thus we see that the same ends may be arrived at along various, and sometime[s] wildly different, routes. Correspondingly, very seldom is the convergence so exact as to make the organism or structure indistinguishable. (p. 301, emphasis added)

So, young Rachael, here’s the other lesson I hope you will learn from this and, I think, you’re on your way to that knowledge because you’ve promised to return to the park at the next opportunity. Be fully confident that when you and Gabrielle return to Dinosaur Park, history will not repeat itself. It will be different the next time around. Even in Simon Conway Morris’ view, the exact same outcome will not come to pass. Take solace in that, even as you lick your wounds from the experience of last Saturday.

Of course, do understand, it could well be worse.

My advice, Rachael, when you do go on that dream fossil hunt in South Dakota, follow your instincts and leave your older sister at home.

Thursday, November 19, 2009

Paleontological Nicknames -- Addendum

In my previous post (November 17, 2009), I considered the propensity in paleontology for the nicknaming of hominid specimens (I fear the specific focus wasn't clear in the title). I've been thinking about why there should be this propensity. Although naming things seems to be one of our species' natural roles, these fossils, in particular, invite the nicknames by which they are popularly known (in lieu of their curated identifications, such as WT 17000) because, after all, they are from individuals who were human-like or, indeed, human.

ScienceDaily just posted a story about a recent analysis of the Homo floresiensis specimen LB1, concluding that, indeed, she is from a new species of Homo ('Hobbits' Are a New Human Species, According to Statistical Analysis of Fossils, ScienceDaily, November 19, 2009, link here). LB1 has a propensity for garnering nicknames. She was the partial fossil skeleton found on the Indonesian island of Flores that initially prompted the nickname the hobbit, which is now applied to all of this species (see Kate Wong's article Rethinking the Hobbits of Indonesia, Scientific American November 2009, link here). So, in light of the loss of an exclusive nickname, I suppose it's not surprising that she has a new one all her own, or actually two. As the ScienceDaily piece notes, LB1 is also known as Little Lady of Flores or Flo.

Tuesday, November 17, 2009

Paleontological Nicknames

Is nicknaming more prevalent in paleontology than in other scientific or non-scientific academic fields, in different cultures, or in different environments, such as elementary school playgrounds, locker rooms, the cinematic fantasy world of beautiful and clever thieves (see, for example, The Italian Job), or the nether world of rap? I’m beginning to think that it might be. Maybe, though, it’s only that the nicknames and stories are more interesting.

Multiple names, formal and not so formal, are part of the paleontological (and for that matter, biological) world. Certainly the development of Linnaean scientific classification leaves plant and animal species with a couple of names, their scientific names and their common names. Still, that’s not truly nicknaming since the common names for nearly all plant and animal species presumably preceded the coining of the more formal scientific names. Actually, what I’m really interested in is the nicknaming in paleontology of specific individuals or specimens.

Hominid Nicknames

I have to admit that my view of all of this is prejudiced by a fair amount of recent reading on human evolution. With great frequency, it would appear, a newly discovered hominid skeletal fragment or collection of fragments is not only given a scientific name, which often stakes a claim to a new species, if not a new genus, but the individual specimen is graced with a new nickname. Perhaps the best known is Lucy, the nickname given a specimen of Australopithecus afarensis with a remarkably complete skeleton (40 percent of a skeleton is remarkable among ancient hominid fossils – the nickname comes from the repeated playing of the song "Lucy in the Sky with Diamonds" in camp the night of her discovery). Recently, those who pay attention to these things have been enveloped by the nickname Ardi for a specimen of what’s been identified by her discoverers as Ardipithecus ramidus (derivation of the nickname is obvious), and, then, there’s the hobbit, the nickname for a specimen of the recently discovered so-called Homo floresiensis, a diminutive creature with a mixture of Homo, ape, and australopithecine traits. Tolkien’s the source of the latter nickname, and I guess, at this stage, all members of the species of H. floresiensis are being called hobbits. [I wrote an earlier post on Lucy and Ardi, and discovery in general.]

But, these names only scratch the surface of the nicknaming in paleontology. A few nicknames might suffice to paint the rich picture. For instance, there’s the specimen known as Dear Boy and also as Zinj. Why Dear Boy? I don’t know but that’s apparently what Louis and Mary Leakey called it after its discovery. Its original scientific name, Zinjanthropus boisei, accounts for its second nickname. Among my favorites is the Black Skull, a partial skull from a specimen of Australopithecus aethiopicus found in West Turkana (Kenya).

Its nickname derives from the coloring of the skull and is much more dramatic a name than WT 17000, its curated, formal identification. [See Ian Tattersall’s book The Fossil Trail: How We Know What We Think We Know About Human Evolution, 1995, and Extinct Humans by Ian Tattersall and Jeffrey Schwartz, 2000.]

The paleontological nicknames that most intrigue me are those that, over time, have become totally and completely wrong; whatever plausibly generated the nickname in the first place no longer applies. But, still, the nickname lives on.

For example, take Mrs. Ples (see image below). She lived some 2.5 million years ago and is in the Australopithecus genus, possibly an ancestor of Homo. When first discovered, the nickname bestowed on her made some sense – she was, after all, initially set in the genus Plesianthropus. But, not only has the genus designation shifted, but so perhaps has her gender. She may well have been male. Still, he remains Mrs. Ples. [See, Richard Dawkins, The Ancestor's Tale: A Pilgimage to the Dawn of Evolution, 2004]

Then there’s the marvelous Red Lady of Paviland. In 1823, Oxford University geologist William Buckland explored the Paviland Cave, in South Wales, which the year before had yielded fossils from animals, including mammoths. He described discovering a human skeleton covered with a red iron ore dye. At its thigh were periwinkle shells and beside its chest were ivory rods and pieces of ivory rings. Stephen Aldhouse-Green, Professor of Human Origins, University of Wales, describes the derivation of its nickname:
In the field, Buckland had identified the skeleton as male, suggesting that the bones were those of a Customs Officer murdered by smugglers. By the time of publication later that year, however, the gender had changed with a new and better story. . . . The ochre-stained skeleton had become a 'painted lady' who serviced the needs of the Roman soldiers garrisoned in the camp on the hill above the cave. It was a good story.

In fact, the reality is much better than the “good story” Buckland came up with. The Red Lady is a young Homo sapiens male who, based on recent research, lived about 26,000 ago, in a period of advancing ice sheets that were nearing the place where his skeleton was found. As Aldhouse-Green puts it, at this Upper Paleolithic site, “The ceremonial burial of the 'Red Lady' involved the interplay of art and consciousness which combine in an act that is simultaneously creative and symbolic.” The burial apparently is similar to others in the same period. Its elements included placing the body next to the cave wall, positioning animal remains by the grave, marking the head and feet with stone slabs, coloring and decorating the body, and, possibly, removing its head (none has been found at the site). Further, he speculates that the site may have had a special meaning for these Stone Age people who, even as humans were abandoning Britain in the face of the deteriorating climate, returned to the cave in order to bury the body there. Finally, Aldhouse-Green notes, “At the time when the 'Red Lady' was unearthed she - or rather he - was not only the first such burial to be found but also the first human fossil ever to have been recovered anywhere in the world.” [Stephen Aldhouse-Green, Great Sites: Paviland, British Archaeology, October, 2001, link here]

Some 85 years later, he’s still known as the Red Lady of Paviland. Johann Georg Von Zimmermann, 18th century Swiss physician and philosopher, certainly had it right when he asserted that “a nickname lasts forever.”

An Etymological Aside

The etymology of the word nickname is fascinating in its own right. In Middle English, the additional name given to a person was known as an eke name. Eke was Old English; apparently as a noun it meant “additional” and as a verb it meant “to augment” or “to supplement” (e.g., eke out a living). The phrase an eke name at some point was misdivided into a nekename.

One type of nickname is a sobriquet which is a friendly or funny nickname. Its etymology is charming – sobriquet comes from the Old French meaning a “chuck under the chin.”

[Among useful sources on etymology are The American Heritage Dictionary of the English Language, 3rd Edition, 1996; and Word Origins . . . And How We Know Them by Anatoly Liberman, 2005, link here]

Sources of Images

The image of the Black Skull is from the Smithsonian Institution (Human Origins Program), link here.

The image of Mrs. Ples is from the Sterkfontein Exhibition Guide, published by the South African Maropeng and the Cradle of Humankind World Heritage Site, link here.

Sunday, November 8, 2009

Ichnofossils and Old Home Movies

An ichnofossil I found this past week brought to mind old home movies. Ichnofossils or trace fossils are the fossilized evidence of activities of ancient organisms, coming in such forms as tracks, burrows, or borings. Old home movies are . . . , well, what I really have in mind are those short movies shot on 16 mm film (introduced in the 1920s) or 8 mm film (introduced in the 1930s).

I’ll start with the home movies. In fact, I’ve been thinking a great deal recently about a specific home movie from the 1920s and a batch filmed in the 1950s.

Home Movie, 1920s

A very committed substrata of the baseball fan community is wielding impressive analytical tools in an attempt to decipher a home movie discovered by someone in his grandfather’s collection of movies. The movie offers a very brief, blurry glimpse of a major league baseball game. This is a long look back because the game appears to have been played at some point in the 1920s at Yankee Stadium. A tantalizing pan across centerfield shows a tall pole standing in the field (good Lord, actually in the field of play – “I’ve got it, I've got it.” Bonk!), ads for shaving gear adorning the outfield walls, and a blimp floating beyond the stadium. What has the fanatics in a lather is the presence of a large, broad shouldered, slim-hipped player in this film clip – we see him striking out and apparently also playing right field during the game. The operating consensus is that it’s one of the baseball immortals, Babe Ruth. And that’s what makes the effort to identify the specific game a mission from God, particularly because there is no film of the Babe playing in the outfield during a regular game in Major League Baseball’s film archives. Baseball, for better or worse, is in love with its history. (Babe Ruth Like You've Never Seen Him Before, by John Branch, The New York Times, October 8, 2009 – link here to article; link here to Branch’s NYT blog posting; link here to followup piece by Branch)

So, here we have film of an event whose every important action is presumably recorded in a score sheet somewhere and described in newspaper articles. But, beyond the general agreement that this film shows the Babe in Yankee Stadium, perhaps shows him playing right field in a regular game, and certainly appears to show him striking out, we are left with myriad uncertainties. Most importantly, we cannot say with confidence when this game was played. 1928? September 9? Against the Philadelphia Athletics? Still, despite the debate over when the event took place, I believe we’re seeing Ruth in action, something I always find surprising – whoa, the man was real, not just a myth.

Home Movies, 1950s

My wife’s grandfather shot many (oh, so many) home movies during the 1950s, never quite understanding that a three minute still life film (of, say, an azalea bush) left something to be desired. (Andy Warhol stole the idea and turned it into art.) He, my wife’s grandfather, not Warhol, also had little appreciation for the panning shot. Even those that he managed to take came right to the verge of capturing essential images and stopped. One of the most frustrating thing about home movies, particularly these, are the missing details; often the truly interesting people or objects are just off camera or hopelessly out of focus in the background. It doesn’t necessarily help to be watching them with some of those who had starring roles in the films. Yes, that’s Cousin Joey on Grandad’s tractor. No, wait, that’s his brother. Isn’t it? Seeing one’s wife at age six – yes, there’s something disquieting about that. But, wait, who is that really?

Got to love those grandfathers with home movie cameras. Despite the grainy, herky-jerky images and crude filming techniques, these movies offer very interesting views of the recent past that can be as intriguing in what they reveal as they are frustrating in what they suggest. The Babe Ruth film and the 1950s family films are records of events, they capture action (what there is of it) and can be paused and parsed. Yet, just a few generations have passed and we are unable to recreate these events with precision.

Ichnofossil, 2009 (and Over 65 Million Years Ago)

Recently, while rooting through the spoils piles of material dredged in the building and maintenance of the Chesapeake and Delaware Canal, I came across a small fossilized shell, a single valve from a pelecypod known as Exogyra – a mollusk. This particular specimen, 2 cm or a bit more than 3/4ths inch in length, lived in the Cretaceous period. As I turned it over, I realized that I could tell, with some certainty, how this specific organism had died. There, up toward the beak (the point at which initial growth of the shell begins), was a dark hole that something cut through the shell millions of years ago; the hungry perpetrator (a gastropod is the likely suspect) then digested its prey. As stark as a bullet hole in a skull. (Oh, sure, I do know about that because I watch Bones and all of TV shows with forensic scientists, medical examiners, and pathologists.)

This find is a two-in-one. The hole is itself a trace fossil. It is likely that this hole is the ichnofossil known as Oichnus Bromley 1981 (this is the name of the trace fossil, not of the organism that made it). Here’s Richard Bromley’s cautionary note about what we may not actually know from this ichnofossil:
Oichnus is produced by a wide range of trace-making organisms. As the trace fossils contain few fingerprints to indicate the taxonomic position of the trace-maker, confident identification of the borer is not common. Small (millimetric) round drill-holes are dominantly produced today by predatory gastropods of the Naticidae and Muricacea, both arising in the Cretaceous . . . . (A Stratigraphy of Marine Bioerosion, a chapter by Richard G. Bromley in The Application of Ichnology to Palaeoenvironmental and Stratigraphic Analysis, edited by D. McILroy, 2004, p. 467 – link here

“Few fingerprints” – ah, crime scene language. The perp left few fingerprints and we’re not sure who did the foul deed, but, we know from that hole generally what happened.

Ichnofossils and home movies – simultaneously useful and frustrating, and on occasion very startling.
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