Life Traces of a Master: A Tribute to Dolf Seilacher (Part III)

(This is the third of a three-part series honoring the memory of paleontologist-ichnologist-teacher-artist Dolf Seilacher, who died on April 26, 2014. Part I of the series is here and Part II is here.)

After Dolf’s only trip to Georgia in 1997, I saw and talked with him a few more times, conversations that sometimes involved rocks and trace fossils in the field, but sometimes not. These times and places were in 2003 (Switzerland), 2004 (Argentina), 2006 (the far-off land of Philadelphia), and 2008 (Krakow, Poland).

Plenty of other ichnologists from around the world attended these meetings, too. Many of them I now consider as long-time friends, in which we get back for regular reunions to talk and argue about trace fossils, discussions that are normally accompanied by ritualistic consumption of significant volumes of libations. Almost always in such conversations, though, someone mentions the name “Dolf.” This then leads to animated discussions of his articles, remembrances of personal encounters with him (which usually involve some sort of strongly worded disagreement about a scientific idea), or telling stories about field trips, where Dolf noticed something extraordinary that everyone else had missed. In other words, even when Dolf wasn’t there, he was still present.

Seilacher-Ichnia-ArgentinaIf invited to speak at a gathering of ichnologists, Dolf Seilacher was never shy about saying “yes.” Here he addresses participants of the 1st International Ichnological Congress (Ichnia), held in Trelew, Argentina in 2004. (Photograph by Anthony Martin.)

As opposed to his trip to Georgia in 1997, the 2003 meeting in Switzerland was more-or-less in Dolf’s backyard, a short trip from his home in Tübingen, Germany. This was the International Ichnofabric Workshop, a biannual meeting of ichnologists that’s been taking place since the 1990s in various trace-fossil-rich places throughout the world. I love these meetings because of their balance between time spent blabbing in conference rooms and time spent in the field, looking at trace fossils: typically three days inside, three days outside. Now that’s what I call “fair and balanced.”

Dolf-Roland-IIW-BaselHow would you like to have your “Dolfing“? Inside or…

Dolf-Field-Switzerland…outside? (Both photographs taken by Anthony Martin in July 2003, Switzerland.)

Many of the trace fossils we encountered on the field-trip portion of the workshop were originally from deep-marine environments, made 30-50 million years ago by invertebrate animals that lived in on ocean-floor sediments hundreds or perhaps thousands of meters below the surface. Later, when the Alps were uplifted by colliding plates, this oceanic-continental mashing transported the trace fossils, resulting in seemingly anomalous signs of life from a deep seafloor, but in alpine settings. Dolf was one of the world’s experts on deep-sea traces, and among the few ichnologists to have taken a submersible ride (DSV Alvin) to more than 3,500 m (11,500 ft) down, highlighted in the IMAX film Volcanoes of the Deep Sea (2003). So it was no surprise when our first encounters with these trace fossils in the field prompted him to share his considerable knowledge about them.

Although Volcanoes of the Deep Sea is a fine documentary film in its entirety, for now just watch the first three minutes here to see Dolf in the field, looking for deep-sea trace fossils and talking about his mistress, who he met on his honeymoon. (Spoiler alert: His “mistress” is a trace fossil, and a complicated one, named Paleodictyon.)

Seilacher-SpirorapheDolf was clearly excited about sharing what he knew about the deep-sea trace fossils during our Ichnofabric Workshop in Switzerland. And he knew a lot. (Photograph taken by Anthony Martin in July 2003, Switzerland.)

The 2004 meeting in Argentina was a big deal for ichnologists, as this marked the first International Ichnological Congress, more briefly called Ichnia. More than a hundred ichnologists of varied interests, backgrounds, and nationalities gathered in Patagonia, Argentina, first for a glorious four-day field trip based out of Comodora Rivadavia, then for the congress itself in Trelew. Dolf joined us for the latter, and people who delivered talks in the sessions soon realized they were not going to leave the stage until Dolf asked them a question or made a comment about their work. At the time, he was 79 years old, but clearly was not ready to slow down teaching all of us.

Bromley-Pemberton-Seilacher-IchniaA rare circumstance: three of the most significant ichnologists in the world leaving fresh and contemporaneous footprints in the same habitat. From left to right is Richard Bromley (Denmark), George Pemberton (Canada), and Dolf, who was accepting an award from the organizers of this Ichnia. Jorge Genise’s hands (left) for scale. (Photograph by Anthony Martin, taken in Trelew, Argentina in April 2004).

The 2006 meeting in Philadelphia was significant, as this was for a symposium in honor of Dolf’s long and successful career. Organized as a session within the Geological Society of America meeting, it attracted so many ichnologists that the symposium lasted the entire day. In our talk, Andy Rindsberg (mentioned in my last post) and I decided we would cover one of Dolf’s favorite topics, the traces made by animals when they stop, nicknamed “resting traces.” In planning our talk, we knew Dolf would appreciate some good-natured poking fun at his expense. So we decided to lampoon both his authority in our field and his penchant for smoking good cigars through the following two slides (shown here side-by-side).

Freud-Seilacher-CigarTwo slides shown in succession at the Seilacher symposium, held in the 2006 Geological Society of America meeting in Philadelphia, Pennsylvania. Translation on the right is “Sometimes a resting trace is just a resting trace,” and I think you can figure out the one on the left now. I don’t know the photo credit for Dr. Freud, but the one on the right was taken by Andy Rindsberg at the Seilachers’ home in Tubingen, Germany in 2006.

It was a success. Dolf was sitting in the front row while I gave my talk, and I’ll never forget his delighted smile when he saw the image of Sigmund Freud dissolve into his, with an almost perfectly mirrored pose.

The last time I saw Dolf was in Krakow, Poland, and at the second Ichnia meeting in 2008. His presence was doubly appreciated by all of us, as Jagiellonian University was also hosting – at the same time – Dolf’s pride and joy, the Fossil Art exhibit.

Fossil-Art-Sign-KrakowIt’s a sign! Advertising the exhibit Fossil Art, that is. In this instance, the venue was at Jagiellonian University in Krakow, Poland, and in 2008. (Photograph by Anthony Martin.)

However, it was at this meeting where Dolf showed us a side we had almost never seen, but one that was completely appropriate for where we were. Alfred Uchman, the meeting organizer (and one of the world’s experts on deep-sea trace fossils), had asked Dolf to speak at the opening of the meeting on an ichnologically themed topic of his choosing. I don’t remember the main topic of his presentation, and the reason why for my faulty memory is because of what happened first.

Dolf began his talk with a deeply heartfelt and remorseful apology. In an awareness of both history and place, he told us how the grand room in which we were seated was where, in 1939, Jagiellonian University officials had handed over control of this esteemed institution – one of the oldest universities in the world and the intellectual home of Copernicus – to invading forces of Nazi Germany. Dolf, as a German citizen, a World-War II veteran who fought on the side of the Nazis, and who shared a first name with a certain genocidal dictator from Germany, expressed his shame and regret about what had happened in that place and then. I looked around the room and recall sensing the surprise we all felt at his  expression of regret, but also its poignancy and sense of redemption. He then went on and delivered his scientific talk, but it had become one overshadowed by our realization of how horrific histories and inquisitive inquiries are shared facets of our humanity.

Then there was Fossil Art. I remember seeing the first iteration of this traveling display in Germany in 1994, then elsewhere. This exhibit consists of life-sized reproductions (epoxy resin casts) of rock slabs, most of which held gorgeously intricate and intriguing trace fossils, but some with body fossils and physical sedimentary structures, such as ripples and mudcracks. At this meeting, we were privileged enough to get a guided tour of the exhibit by Dolf himself, who gave an introduction to its purpose as a way of engaging our minds and senses with beautiful patterns in rocks, many of which were made by animals from millions of years ago.

Seilacher-Fossil-Art-2Seilacher-Fossil-Art-1Dolf Seialcher introducing Fossil Art to a gathering of ichnologists at Ichnia 2008 in Krakow, Poland. (Photographs by Anthony Martin.)

Many of these reproductions received fanciful titles, such as The Trilobite Circus of Penha Garcia and Witch Broomings, and are mounted like works of art, with carefully arranged lighting accentuating their features. These “slabs” also have Dolf’s written explanations in placards next to them, describing and interpreting their geological significance, but also marveling at their beauty. Is it art, or is it science? Yes. Anyway, I’ll just let these images speak for this masterful blending of natural, aesthetic beauty and scientific information.

Cambrian-Beach-Party-Fossil-ArtCambrian Beach Party II, representing trace fossils made by large slug-like animals on a beach about 500 million years ago. (Photograph by Anthony Martin, taken in Krakow, Poland in 2008.)

Trilobite-Circus-Fossil-ArtThe Trilobite Circus of Penha Garcia, a collection of exquisitely preserved trilobite burrows from Portugal, preserved as natural casts. (Photograph by Anthony Martin, taken in Krakow, Poland in 2008.)

Trilobite-Pirouettes-Fossil-ArtTrilobite Pirouettes, more natural casts of trilobite burrows, but showing looping and stopping (“resting”) behaviors. (Photograph by Anthony Martin, taken in Krakow, Poland in 2008.)

More ichnology meetings took place since then: the third Ichnia meeting in Newfoundland, Canada (2012), and the most recent International Ichnofabric Workshop in Çannakale, Turkey (2013). Dolf did not physically attend either meeting, which did not surprise anyone, as he was in his late 80s, and we were starting to hear stories about his failing health. Nevertheless, a day never passed without his name coming up in conversation. So although most of us had not seen him since 2008, his ideas, personality, and methods seemed permanently attached to us, akin to some of the fossils he had studied.

Now that Dolf is gone and we are left with his considerable life traces, what would be  the best way for all of us to remember him? I suggest we do it through the flattery of imitation.

We are living in a time when science is very popular, even in the U.S., evident from TV shows like Cosmos and Your Inner Fish, as well as many clear and wonderfully written  science books. A few people have even declared that we’ve entered a “golden age” of science communication. Yet basic scientific research is also under assault from anti-science political forces, ones that insist on alternative realities where opinions are given equal (or superior) weight when compared to factual evidence. Moreover, mainstream academia is currently undergoing an administratively led collapse from within, as U.S. universities move more toward a corporate model that places higher profits over discoveries, knowledge, and teaching.

Still, through Dolf Seilacher’s life and accomplishments as a scientist, teacher, and artist, he showed a way to side-step the current chaos. Through his practices, he demonstrated how nearly all of us can do science and make discoveries every day by simply using our senses, pencils, paper, and intellects. Just to be clear, this is not a call to Neo-Luddism, in which we abandon our precious iPads and laser scanners while chanting incantations honoring our pre-technological ancestors. Instead, it is one that asks us to rediscover these basic skills – observing, drawing, and imagination – for conducting science, discovering, learning, and passing on new-found insights to future generations. In short: be more like Dolf.

Danke und Auf Wiedersehen, Dolf, for the gifts you gave us, traces that will continue long after you have become part of the earth and life you so loved studying.


Seilacher, A. 2007. Trace Fossil Analysis. Springer, Berlin: 226 p.

Seilacher, A. 1997, 2008. Fossil Art. (Two versions of this book were published, one through the Royal Tyrell Museum of Palaeontology in 1997, which was 64 page long; the other was through CBM Publishing in Laasby, Denmark, and was 101 pages long. The latter book can be purchased here.)

Life Traces of a Master: A Tribute to Dolf Seilacher (Part II)

(This is the second in a three-part series honoring the memory of ichnologist-paleontologist-educator-artist Dolf Seilacher (1925-2014). For Part I, please go here.)

Dolf Seilacher and I crossed trails again in the fall of 1997, but through my initiative and in my backyard, here in Georgia. After the Evolutionary Biology Study Group at Emory University hosted a series of prominent biologists on the Emory University campus – such as George C. Williams, Richard Lewontin, and the Grants (Rosemary and Peter) – its director asked me which paleontologist we might bring to campus. Having invited theoreticians and lab-based or field biologists as our main guests, he wanted to give the members of our group more of a “deep time” perspective on evolutionary processes. So I immediately said, “Dolf Seilacher.”

Seilacher-Coca-Cola-EmoryDolf Seilacher in Melton’s App & Tap, a neighborhood pub near the Emory University campus that served both Coca-Cola (which has economic connections to Emory) and proper adult beverages, the latter necessary for fueling meaningful paleontological conversations. (Photograph by Anthony Martin, taken in Atlanta, Georgia 1997.)

I recall a few snobbish members of the group doubted that any paleontologist could be a real evolutionary scientist: after all, paleontologists don’t do “experimental work.” (Yes, I’ve actually heard this smug, self-important drivel emit from the mouths of proudly lab-bound neontologists, making Sheldon Cooper look downright open-minded by comparison.) I was also at a university that had jettisoned its Department of Geology only eight years previously, meaning I had little support in my on-campus academic community for hosting an earth scientist. However, Dolf had won the Royal Swedish Academy of Sciences Crafoord Prize just five years before, thus he qualified as prestigious enough for most of the doubters. (Needless to say – but it bears saying anyway – none of his prejudiced skeptics had similar honors.)

Fortunately, Dolf did not disappoint, and hosting him at Emory University was among the most intellectually exhilarating three days I’ve experienced in the past 24 years at my institution. I had him mostly to myself on his first day in Atlanta, but we were joined by fellow ichnologist and friend Andrew (Andy) Rindsberg for dinner, with both of us feeling as if we had the world’s best private tutor in ichnology for that brief time. The next day, Dolf did a lunchtime seminar for the Evolutionary Biology Study Group, then later that afternoon delivered a talk in a big room open to the entire university and the general public. For his last full day in Georgia, he insisted we take him out in the field to see some of the Ordovician-Silurian rocks in the northwest corner of the state. (Other than transferring planes in Atlanta’s airport, Dolf had never been to Georgia and wanted to see our trace fossils.)

His second day in Atlanta, he began his engagement with the Evolutionary Biology Study Group, which was composed mostly of biologists, anthropologists, and psychologists; Andy and I were the lone paleontologists there. The lunchtime seminar was held in a cramped room, and most people there were awkwardly holding flimsy paper plates weighed down by slices of cheap pizza. The overall mood was one of curiosity, as Dolf was a complete unknown to most people there. (Remember, this was 1997: “Googling” was still a year away from being anything, let alone a verb.)

His seminar topic was on fossil tracks, and he started with the classic historical example of how some Early Triassic tracks from Germany (named Chirotherium) had been badly misinterpreted by some of the greatest scientists of their time, such as Alexander von Humboldt, Richard Owen, and Charles Lyell. Later, with more scrutiny and the application of a few key ichnological principles, other scientists revealed what animals made them and how, which Dolf explained in his book Trace Fossil Analysis (2007, p. 6-7).

Seilacher-Chirotherium-AnalysisDolf Seilacher’s visual explanation for how the anatomy and dimensions of a tracemaker, its behavior, and the original substrate (a firm mud) all contributed to making a fossil trackway from the Early Triassic Period (about 245 million years old). He also included  explanations of previous interpretations for these tracks and when they were proposed (middle right), neatly summarizing the progression of the science done on these tracks. (Figure from: Seilacher, A., 2007, Trace Fossil Analysis, Springer, p. 7.)

Wrong-Way-Hands-Fossil-ArtA reproduction of the Early Triassic (about 245 million-year-old) rock slab with mudcracks and Chirotherium tracks, both preserved in convex relief as natural casts. I said “reproduction” because this is a epoxy resin cast made from a latex mold that was also colored to mimic the original rock. Does this sound like a work of art? Well, as a matter of fact, this was one piece in a show Seilacher conceived called Fossil Art. (Photograph by Anthony Martin, taken in Krakow, Poland in 2008.)

Once introduced, Dolf took off, and his audience went with him. In a lively, mesmerizing presentation, Dolf deftly interwove history of science with detective-like applications of ichnology, anatomy, sedimentology, and evolution, all delivered with his trademark enthusiasm, humor, and charisma.

In one memorable instant, he used his hands and arms to play-act the wrongly interpreted gait of the Chirotherium maker, in which this wretched imaginary animal had to cross its limbs as it walked. (Later, paleontologists figured out its so-called “thumb” was actually its outermost digit, thus erasing any need for the animal to cross-step.) He then pantomimed the more correct gait, again bringing across his points far more effectively than if he had used, say, a computer-animated reconstruction of the tracemaker. The audience was enthralled, enchanted, engaged, or whatever words science communicators use to describe what happens when a speaker is rhetorically kicking butt.

How did I know Dolf’s talk was a success? About five minutes into it, one of the most egotistical and pedantic curmudgeons in the Evolutionary Biology Study Group (who may or may not have been an anthropologist) turned to me and said with genuine delight, “This guy is terrific!” Yes, he was.

Later that afternoon, Dolf gave a lecture in a, well, lecture hall, with about a hundred people attending. For me, this was less exciting than his noontime talk because trace fossils and ichnology only figured briefly in its message. Instead, it was more about the “big picture” of evolution as reflected by the fossil record, with emphases on constructional morphology and biological structuralism, and connecting these to the evolution of animal behaviors. Some of these concepts – which I won’t even try to explain here – represented expansions on research by Dolf’s Ph.D. advisor, Otto Schindewolf. Nonetheless, he delivered a thought-provoking lecture, and enthusiastically answered a variety of questions when the time came.

Dinner at a Lebanese restaurant after the lecture was an opportunity to see yet another side of Dolf. For instance, soon after our party had been seated, he and the restaurant owner exchanged pleasantries (and jokes) in Arabic. I had forgotten that Dolf taught at the University of Baghdad early in his career and did much field work in Libya and other parts of the Middle East. The dinner – which included many field stories Dolf had experienced around the world – went well into the night, but did not hinder Dolf’s observation skills at the end of it.

As we exited the restaurant, he pointed to the cement on the doorstep and said, “Look, evidence of a former biomat, helping to preserve this footprint.” We looked down and saw where a shoe-clad human had stepped into the originally wet cement. But wrinkle marks around its edges – as Dolf explained – showed where plastic sheeting had been placed over the cement in a vain attempt to prevent people from stepping on it. It was a moment when we felt like Watson to his Sherlock.

Following his triumphant visit to the Emory campus in Atlanta, Dolf was then ready to experience something that really mattered, like trace fossils. The next day, we took him to northwestern Georgia to look at trace fossils in the Ordovician-Silurian rocks there, a mere 2.5 hour drive from Atlanta.

We had a varied group, composed of a few paleontologists – Andy Rindsberg, Sally Walker, and me – along with the director of the Evolutionary Biology Study Group (Michael Zeiler), a couple of evolutionary biologists and biology graduate students, and a few undergraduate students from one of my geology classes. Our only goal for the day was to see the I-75 Ringgold roadcut, which through its height, breadth, and gently tilted strata afforded an opportunity to stroll along its length, find many trace fossils, and put them into the context of changing environments from more than 440-430 million years ago.

Dolf-Seilacher-Ringgold-Georgia-1The start of the field trip with Dolf Seilacher to see Ordovician-Silurian rocks near Ringgold, Georgia. This photo was taken about 10 minutes before he took over the field trip, which immediately followed Andy Rindsberg and me getting “Dolfed.” (Photograph taken by Anthony Martin in November 1997.)

Andy and I were thrilled to have Dolf at this outcrop with us because we had done a lot of work there, and we wanted to show off what we had found. Andy studied the Ordovician and Silurian trace fossils there in an M.S. thesis done at the University of Georgia, and I completed a bed-by-bed analysis of its Upper Ordovician rocks as part of my Ph.D. dissertation, also at the University of Georgia. Because we worked for the same graduate advisor (Robert “Bob” Frey), Andy and I communicated well with one another, and we mostly agreed on what trace fossils were there and what they meant. Moreover, Frey had published a paper with Dolf in 1980 (well before he died in 1992). Thus Andy and I felt as if we were fulfilling an ichnological legacy by taking Dolf to see trace fossils that Frey had studied here in Georgia.

Dolf-Seilacher-Ringgold-Georgia-2A first sign that Andy and I were not leading this field trip: within minutes of arriving at the site, the group gathered around Dolf to listen to what he had to say about the Late Ordovician rocks under our feet and around us. Did I mention this was his first time there? (Photograph by Anthony Martin, taken near Ringgold, Georgia in November, 1997.)

Dolf-Seilacher-Ringgold-Georgia-3Probably my favorite photograph of Dolf, showing him in full lecture mode while surrounded by Late Ordovician rocks in northwest Georgia. His synapses also might have been firing double time because of the caffeinated beverage he picked up at a Golden Gallon convenience store just beforehand. (Photograph by Anthony Martin, taken near Ringgold, Georgia in November, 1997.)

When we got to our destination, we parked and walked a short ways to our first stop. Rather than going directly to the road cut, we first looked at big slabs of sandstone in a former quarry site. These sandstones were from the Late Ordovician Sequatchie Formation, and they made for wonderful teaching specimens, containing many fossil burrows, mudcracks, and reddish clay, all indicating formerly intertidal environments. However, Andy and I didn’t know what made the burrows. Little did we know (but we should have), we were about to find out.

After Andy and I gave a brief introduction to this site and a preview of what to expect at the outcrop, Dolf strolled over to a large slab of sandstone, and nonchalantly placed his hand over a bump on its surface. “This trilobite resting trace shows how they were well adapted to living in intertidal environments at this time…” he began.

Andy and I exchanged startled looks. “Trilobite resting traces?” we both said. In all of our years of field work at this site, we had found very little evidence of a trilobite presence. We also had never recognized a trace fossil showing where a trilobite dug into mud or sand in one place and left an outline of its body, a so-called “resting trace,” sometimes called Rusophycus.

That’s when we realized it. We’d been Dolfed. And on our own field trip.

Fortunately, we didn’t care. Dolf then went on to propose that the more common burrows in these rocks were also made by trilobites, but smaller ones. I’ve written previously about this trilobite-themed revelation and how Andy and I tried later to disprove it, only to find that Dolf was probably right. This served as yet another example of why experience matters in ichnology, and why we ichnologists should always listen to those who have it.

Dolf-Seilacher-Ringgold-Georgia-4Dolf in action, as he started to put together the story of how trilobites were burrowing on and into tidal flats more than 400 million years ago in a place we now call Georgia. Notice how Dolf was using pencil and paper to assist in his explanations of what was in front of us, no doubt drawing out his conclusions. (Photograph by Anthony Martin, taken near Ringgold, Georgia in November, 1997.)

Dolf-Seilacher-Ringgold-Georgia-5Dr. Sally Walker, getting a close look at the bedding-plane surface of the sandstone, which is loaded with natural casts of mudcracks. But wait: what’s that blurry, whitish bump in the lower left corner?

Dolf-Seilacher-Ringgold-Georgia-6Why, that’s a trilobite resting trace, the first ever found in this formation and locality. Thanks for the Dolfing, Dolf. (Both photographs by Anthony Martin, taken near Ringgold, Georgia in November, 1997.)

Seilacher-Trilobite-Resting-Trace-DrawingDon’t quite see the trilobite resting trace fossil, and you think it’s a just a random bump on that rock surface? Here’s an illustration by Dolf that should help to enlighten. Take a look at the left-hand side of this figure with his depictions of trilobite resting traces, then look again at the photograph of the “random bump.” Yes, that’s right: you’re wrong. And you know what? It’s perfectly fine to be wrong in science. Just make sure you learn from your mistakes. (Figure from: Seilacher, A., 2007, Trace Fossil Analysis, Springer, p. 39.)

The rest of the field trip seemed almost anti-climatic after Dolf’s discovery, but it was still quite enjoyable. We left the quarry site and walked along the roadcut itself for the next few hours, stopping to look at whatever caught our attention. Its titled strata meant were were going forward in geologic time, from oldest to youngest (Middle Ordovician –> Early Silurian). This provided a nice lesson for the geological novices in our group in how to interpret changing environments through time. We found more trace fossils, and even a few body fossils, giving everyone plenty of paleontological stimulation to get them through that day and beyond.

Dolf-Seilacher-Ringgold-Georgia-7Dolf Seilacher, master ichnologist and consumate teacher. We will greatly miss his pointing out the obvious to the oblivious. (Photograph by Anthony Martin, taken near Ringgold, Georgia in November, 1997.)

When it came time to leave, we walked out with Dolf, feeling exceedingly grateful for his requesting this trip. Later, we joked with him about the success of his “first visit to Georgia.” Alas, we did not know then that it would also his last. Nonetheless, what remains are the provocative thoughts and methods he imparted on so many of us during his brief time here, no doubt inspiring future generations of paleontologists, ichnologists, and all others interested in learning about the wondrous history of the earth.

Seilacher-Ringgold-14A group picture following our field trip with Dolf Seilacher to northwest Georgia in November 1997 (and much gratitude to whoever suggested it and took it). For me (far right, big hat), the road behind us seems to symbolize a trail he blazed for us to follow. Thanks for all of the cognitive traces, Dolf: may they continue to reach into the fossil record.


Seilacher, A. 2007. Trace Fossil Analysis. Springer, Berlin: 226 p.


Deep in the Dinosaur Tracks of Texas

Given the continuing public mania over dinosaurs, and recent important discoveries of yet more exquisite specimens of feathered theropod dinosaurs discovered in countries far away from the U.S. (here and here), it is sometimes easy to forget what has long been known about these animals, and right here in my own “backyard” (globally speaking).

Need to see some of the best dinosaur tracks in the world, and you live in the southeastern U.S.? Guess what: you can seen them in Glen Rose, Texas. Not China, Mongolia, Canada, Utah, or some other far-off land inhabited by strange people with unusual customs, but Texas. Saddle up! (Photograph by Michael Blair, taken in Dinosaur Valley State Park, Texas.)

So on July 22, just to jog my memory a bit, I flew from Atlanta, Georgia to the Dallas-Ft. Worth (Texas) airport, and only a few hours later was gazing upon dinosaur tracks accompanied by the burrows of invertebrate animals, both trace fossils having been made more than 100 million years ago. It was a fitting welcome to Glen Rose, Texas, a place famous for its dinosaur trace fossils since the 1930s, and where dinosaurs were an integral part of its culture long before it was cool, hip, and contemporary elsewhere.

In Glen Rose, Texas, the dinosaur tracks are so abundant, you can choose whether to see these just outside of your hotel room, or go to the hotel jacuzzi and pool. Naturally, I chose both. (Photograph by Anthony Martin, taken in Glen Rose, Texas.)

So just how did I end up in Glen Rose, Texas, looking at Cretaceous dinosaur tracks and invertebrate burrows? I was lucky enough to be there as an invited participant in an expedition sponsored by the National Geographic Society. I say “lucky” because luck was certainly a part of it, a fortuitous connection made through my writing a book about the modern traces of the Georgia coast. James (Jim) Farlow, a paleontologist at Indiana-Purdue University Fort Wayne (IPFW) and an associate editor with Indiana University Press, reviewed the first draft of my book, but he was also in charge of this dinosaur-track expedition to Glen Rose. Evidently he was impressed enough about what I knew about invertebrate burrows (or at least what I wrote about them) that he considered me as a possible member for his team of scientists, field assistants, and teachers on this expedition.

Dr. Jim Farlow, the world expert on the Glen Rose dinosaur tracks, having a reflective moment at Dinosaur Valley State Park near Glen Rose, Texas. What’s with the broom? He and other people in the expedition used these to sweep river sediment out of dinosaur tracks submerged in the river. In 100° F (38° C) temperatures. On the other hand, I just described invertebrate trace fossils, which was more of a job, not work. (Photograph by Anthony Martin, taken in Dinosaur Valley State Park, Texas.)

Thus when Jim asked me last fall if I would be interested in joining them to describe and interpret the Cretaceous invertebrate burrows that occur with the dinosaur tracks there, I jumped at the opportunity. The Glen Rose dinosaur tracksites, most of which crop out in the Paluxy River bed in Dinosaur Valley State Park, are world famous for their quantity and quality, and they connect with an important part of the history of dinosaur studies. Going there, experiencing these tracks for myself, and better understanding their paleoecological and geological context would be of great benefit to me, my students, and of course, you, gentle readers.

Just to back up a bit, and clarify for anyone who doesn’t know why these tracks are so darned important, here’s a brief background. In November 1938, Roland T. Bird, an employee of the American Museum of Natural History and a field assistant to flamboyant paleontologist Barnum Brown (the guy who named Tyrannosaurus rex), saw large, isolated limestone slabs with theropod dinosaur tracks in a Native American trading post in Gallup, New Mexico. Upon inquiring about the origin of these tracks, Bird was told they came from Glen Rose, Texas. So he set out in his Buick for Glen Rose to see for himself whether these tracks were real or not, and whether there were any more to see in the rocks around Glen Rose. The theropod track set in the town bandstand – pictured below – was one of the first sites that greeted him, and Glen Rose locals told him about the tracks in the Paluxy River.

Glen Rose, Texas, the only place in the world where the town bandstand has an Early Cretaceous theropod dinosaur track on display. Wish I could also tell you about all of those little holes in the rock with that track, but I can’t right now. Nonetheless, rumor has it they are burrows made by small, marine invertebrates that lived at the same time as the dinosaurs. (Photograph by Anthony Martin, taken in Glen Rose, Texas.)

Bird had hit the jackpot, the motherlode, the bonanza, the surfeit, the, well, you get the point. Not only did the Paluxy River outcrops contain hundreds of theropod dinosaur tracks – many as continuous trackways – but also the first known evidence of sauropod dinosaur tracks.

A couple of beautifully preserved theropod tracks under shallow water in the Paluxy River. Note that the track at the bottom also has a partial metatarsal (“heel”) impression, and look closely for the digit I (“thumb”) imprint on the right. Scale is about 20 cm (8 in) long. (Photograph by Anthony Martin, taken in Dinosaur Valley State Park, Texas.)

Funny how those “potholes” in the limestone bedrock of the Paluxy River have oblong outlines and form regular alternating patterns, isn’t it? Well, them ain’t no potholes, y’all. They’re sauropod tracks, and were among the hundreds recognized as the first know =n such tracks from the geologic record. (Photograph by Anthony Martin, taken in Dinosaur Valley State Park, Texas.)

The discovery of sauropod tracks was as huge as the tracks. Up until then, sauropods were assumed to have been so large that they could not support their weights on land and spent most of their time in water bodies. These tracks said otherwise, that these sauropods were walking along mudflats along with the theropods. In short, the trace fossil evidence contradicted the assumed story about how these massive animals moved. After all, trace fossils are direct records of animal behavior, and if interpreted correctly, can tell paleontologists more about what an animal was doing on a given day than any amount of shells, bones, and yes, even feathers.

Sauropod tracks from the main tracksite in Dinosaur Valley State Park, Texas. The sauropod was moving away in this view, and the trackway pattern is a typical diagonal-walking one, right-left-right. In parts of this trackway, both the manus (front foot) and pes) rear foot registered, something Bird noticed in 1938, his observation accompanied by more than a little bit of excitement. (Photograph by Anthony Martin, taken in Dinosaur Valley State Park, Texas.)

The details preserved in these sauropod tracks are also astounding. Most sauropod tracks I have seen elsewhere, in Jurassic and Cretaceous rocks of the American West, Europe, and Western Australia, are only evident as large, rounded depressions that you would only know are tracks because they form diagonal-walking patterns. In contrast, the Glen Rose tracks include all five toe and claw impressions on the rear feet (pes) and full outlines of the front feet (manus). The original calcium-carbonate mud in the shoreline environments where the sauropods walked, similar to mudflats I’ve seen in the modern-day Bahamas, is what made this exquisite preservation possible. The mud had to be firm enough to preserve these specific details of the sauropods’ feet, but not so soft that the mud would collapse into the tracks after the sauropods extracted their feet.

Beautifully preserved tracks, manus (top) and pes (bottom). Note the five toe impressions in the pes, which along with its size confirms that these were made by a large sauropod. Meter stick for scale. (Photograph by Anthony Martin, taken in Dinosaur Valley State Park, Texas.)

One sauropod trackway, preserved with a theropod trackway paralleling and intersecting it, was actually quarried out of the river and taken to the American Museum. Once there, its pieces stay disassembled for years, before Bird helped with putting the puzzle pieces back together so that it could be used as part of a display there.

Archival video footage of Roland Bird and his field crew working on the dinosaur tracks in the Paluxy River near Glen Rose, Texas. More about this tracksite and its role in the history of dinosaur paleontology is ably conveyed by Brian Switek here.

Photos at the visitor’s center at Dinosaur Valley State Park, showing the sequence of clearing (left) and extraction (right) of the limestone bed containing the theropod and sauropod dinosaur tracks. (Photographs taken of the photographs, then enhanced, cropped, and placed side-by-side by Anthony Martin.)

A lasting trace today of Roland Bird and his field helpers from the 1940s, in which they took out a sauropod and theropod trackway from this place and transported it to New York City. (Photograph by Anthony Martin, taken in Dinosaur Valley State Park, Texas.)

Other than some of the best-preserved Early Cretaceous dinosaur tracks in the world, one other claim to fame for the Glen Rose area, and not such a proud one, is its attraction to evolution deniers, a few charlatans who used the tracks to promote what might be mildly termed as cockamamie ideas. You see, Glen Rose is also the site of the infamous “man tracks.” These tracks are preservational variants of theropod tracks that – through a combination of the theropods sinking into mud more than 100 million years ago and present-day erosion of the tracks in the Paluxy River – prompted some people to claim these were the tracks of biblical giants who were also contemporaries of the dinosaurs. (Perhaps this is as good of a time as any to start humming the theme music for The Flintstones.)

Rare documentary footage of humans and dinosaurs interacting with one another during the Early Cretaceous Period, or the Late Jurassic Period. Whatever. Note the inclusion of other seemingly anachronistic mammals, too, such as the saber-toothed felid Smilodon. Perhaps this footage could be included in the curriculum of some U.S. public schools, providing a formidable counter to the views of 75 Nobel laureate scientists. Then we’ll let the kids decide which is right.

I will not waste any further electrons or other forms of energy by continuing to flog this already thoroughly discredited notion, but instead will direct anyone interested to a thorough accounting of this debacle to some actual scholarship here, summarizing original research by Glen Kuban and others in the 1980s through now that have laid to rest such spurious notions. Speaking of Mr. Kuban, I was delighted to meet him for the first time during while in Glen Rose (we had corresponded a few times years ago). I was even more gratified to spend a few hours in the field with him, discussing the genuinely spectacular trace fossils there in Dinosaur Valley State Park with these directly in front of us. Again, I’m a lucky guy.

The expedition was scheduled in Glen Rose for three weeks during late July through early August, but with so many commitments for this summer, I could only carve out a week for myself there, from July 22-29. Fortunately, this was enough time for me to accomplish what was needed to do, while also having fun getting to know the rest of the expedition crew – teachers, artists, videographers, laborers – and enjoying wonderful discussions (and debates) with colleagues in the field. The people of Glen Rose were also exceedingly welcoming and accommodating to us: we felt like rock stars (get it – “rock”?), and were feted by local folks three nights in a row during the week I was there. Many thanks to these Glen Rose for the the exceptional hospitality they extended to our merry band of paleontologists, geologists, river sweepers, or what have you.

You can’t see it, but I’m standing in a sauropod dinosaur track, which is a little deeper than the rest of the river bed. You also can’t see the invertebrate burrows that are in the limestone bedrock, which is fine, because I can’t show them to you yet anyway. But be patient: you’ll learn about them some day. (Photograph by Martha Goings, taken in Dinosaur Valley State Park, Texas.)

I can’t yet say much more about what I did during that week, as all participants signed an agreement that National Geographic has exclusive rights to research-related information, photos, and video unless approved by them. But if you’re a little curious about the daily happenings of the expedition (which just ended last week), Ray Gildner maintained a blog that succinctly touched on all of the highlights, Glen Rose Dinosaur Track Expedition 2012.

Still, I can say, with great satisfaction, that I did successfully describe and interpret invertebrate trace fossils that were in the same rocks as the dinosaur tracks. Hopefully my colleagues and I will have figured out how these burrows related to environments inhabited by the dinosaurs that walked through what we now call Texas.

All in all, my lone week in the Lone Star State was a marvelously edifying and educational experience, one I’ll be happy to share with many future generations of students and all those interested in learning about the not-so-distant geologic past of the southeastern U.S.

Group photo from the Glen Rose Dinosaur Track Expedition 2012. Names of all participants can be found here, but in the meantime, just sit back and admire those Dinosaur World t-shirts everyone is wearing. (Photograph by James Whitcraft or Ray Gildner: they can fight over who actually took it. Although, the automatic timer on his camera took the photo, so maybe it should get credit instead.)

Further Reading

Bird, R.T. 1985. Bones for Barnum Brown: Adventures of a Dinosaur Hunter. Texas Christian University Ft. Worth, Texas: 225 p.

Farlow, J.O. 1993. The Dinosaurs of Dinosaur Valley State Park. Texas Parks and Wildlife Department, Austin, Texas: 30 p.

Jasinski, L.E. 2008. Dinosaur Highway: A History of Dinosaur Valley State Park. Texas Christian University, Ft. Worth, Texas: 212 p.

Kuban, G.J. 1989. Elongate Dinosaur Tracks. In Gillette, David D., and Martin G. Lockley (editors), Dinosaur Tracks and Traces, Cambridge University Press, Cambridge, U.K.: 57-72.

Pemberton, S.G., Gingras, M.K., and MacEachern, J.A. 2007. Edward Hitchcock and Roland Bird: Titans of Vertebrate Ichnology in North America. In Miller, William, III (editor), Trace Fossils: Concepts, Problems, Prospects. Elsevier, Amsterdam: 32-51.

Of Darwin, Earthworms, and Backyard Science

On the other hand, I sometimes think that general & popular Treatises are almost as important for the progress of science as original work.

– Charles Darwin, in a letter to Thomas Huxley, written in his home (Down House) on January 4, 1865

A combined blessing and burden that comes with travel, especially to new places, is the memory we carry of other places. The blessing part comes from the opportunity to connect previously disparate bodies of knowledge and experiences. This is always exciting for anyone who likes that sort of thing, while also satisfying purported promoters of “interdisciplinarity” (which was probably not a word until academia invented it, then pretended to reward those who practice it). On the other hand, the burden is that these thoughts of previous places can act as a veil, obscuring or overlaying our perception of novel sensations. In extreme cases, these remembrances can smother original ideas, especially if the places of our past are idealized and held as some worldly standard to which all other things must be compared.

What does this roundish stone, lying in the ground of the English countryside south of London, have to do with life traces of the Georgia coast? Good question, and if you’d like the start of an answer, please read on.

This Janus-like duality of travel occurred to me after my wife (Ruth) and I left Georgia for a few weeks of vacation in the United Kingdom, yet once there, I thought about my original home of Indiana and the barrier islands of Georgia. Ruth had never been to the U.K., and I hadn’t visited since attending an ichnology conference and field trip in Yorkshire, held in 1999. Fortunately, Ruth has a friend on the northeastern side of London who generously offered us a place to stay before we headed elsewhere. This refuge gave us a few days to learn what London had to offer us while we otherwise adjusted to cultural and temporal differences.

Among the myriad of educational opportunities in the London area is one that had been on my mind for quite a while, thanks to my writing about the Georgia coast. This was an intended visit to Down House, the former home of Charles Darwin and his family. Down House is located in a rural setting of the greater London area – Downe Village in the former parish of Kent – well southeast of Big Ben and all of the other typical touristy trappings of downtown London. Still, it can be visited via public transportation, which became doable for us Yanks once we figured out the needed connections in the intricate rail and bus system weaving throughout the London area.

From where we were staying, it took us nearly two hours to reach Down House. It was a mildly aggravating sojourn by train and bus, but made much better once we realized that driving there in London traffic with a hired car would have been far worse for both us and other people sharing the road (or sidewalk, as it may be). After our bus dropped us off in Downe Village, we saw a small sign pointing the way to Down House, and walked for  15 minutes on a quiet, country road before reaching our goal, a stroll only occasionally interrupted by brief terror induced when cars approached from the direction opposite of our expectations.

 When you step off the bus in Downe Village, this is one of the few clues that you’re near Darwin’s home, a place where scientific thought and human history changed in a big way.

A signpost in Downe Village provides a clue that Darwin has something to do with this area, although some horse named “Invicta” gets equal billing, and “St Mary the Virgin” gets bigger typeface. Still, it was nice to see Darwin’s visage there, too.

Blink and you’ll miss it: after walking about 10 minutes down the road, here’s the sign pointing the way to Down House. Personally, I thought it could use a neon fringe, or at least some DayGlo™ colors, but subdued is probably the way Darwin would have liked it.

We were also a little surprised at the subdued signage pointing us in the right direction to our goal, and I mused briefly about the homes of people who had far less impact on the advancement of human knowledge and world perspectives whose homes are accorded far more attention and adulation. (Yes, I’m looking at you, Graceland.)

The front of Down House, the home of Charles Darwin and his family from 1842 and after his death in 1882.

Down House is both modest and grand, not palatial at all, but impressive inside. Rooms on the second floor (or first floor, if you live in the U.K.) hold displays with a neatly presented synopsis of Darwin’s life and scientific findings, starting with his little boat journey in 1831-1836 through his grand synthesis of evolutionary principles. The ground floor of the house is more or less restored to the time when the Darwin family lived there, with particular attention paid to Mr. Darwin’s study, which was his main writing and experimentation room, or what modern-day scientists might call his “research space.” This is where On the Origin of Species and most other books of his were born. Infused with a purely fan-boy sort of joy, I was thrilled to be in the same place where many of his revolutionary ideas about evolution became expressed through words.

However, one item in the family living room (drawing room) intrigued me in a special way. It was a piano. This object was certainly used for the enjoyment of Darwin family members and guests, with the degree of delight of course depending on the proficiencies and musical choices of whoever played it. But then I was reminded – by the disembodied voice of Sir David Attenborough, no less – that this was not just a musical instrument, but also a scientific tool. (Disappointingly, Sir Attenborough volunteered this information in a recorded audio tour provided with admission to Down House, not through clairvoyance in a Sir Arthur Conan Doyle sense.) On this piano in the room and in the nearby Down House backyard are the places where Darwin conducted some of the earliest quantitative experiments in the behavioral ecology and neoichnology of terrestrial infauna. Or, in plain English, Darwin used this piano and a few other tools to measure and test the behavior of earthworms as tracemakers in soil.

The rear of Down House, with the two windows to the left looking into the drawing room, where the Darwin family piano is located. Unfortunately, photographs are not allowed in the interior of Down House, hence the external, voyeuristic perspective.

Darwin enthusiasts know well that the last book Darwin wrote was about a personal passion of his, the biology and behavior of earthworms. This book, titled The Formation of Vegetable Mould through the Action of Worms with Observations on Their Habits (1881), encapsulates many observations and conclusions he made from his long-term study of the oligochaete annelids that lived abundantly in the backyard and gardens of Downe House. As some biographers have noted, Darwin became quite a homebody after his years of voyaging on The Beagle, and he stayed close to Down House for much of his life after moving there in 1842. Nonetheless, this geographically restricted lifestyle did not mean he stopped inquiring about the natural world around him. On the contrary, he carried out intensive studies in and just outside of Down House, some of which dealt with earthworms, a subject that interested him for more than half of his life.

Darwin’s wonderment at worms was jump-started by something he noticed nearly thirty years after he innocuously tried to improve the soil in the pasture behind Down House. Told that he could get rid of mossy areas by laying down cinders and chalk, he obediently did so, and checked those same areas 29 years afterwards. It turned out the anomalous sediments had been buried about 18 cm (7 in) below the surface.

Darwin soon suspected this surface was newly made, formed by generations of earthworms bringing up soil over the preceding three decades. Through the technical support of his son Horace, an engineer, Darwin began to measure just how much earth an earthworm could worm. He already knew that earthworms burrowed through, consumed, and defecated sediment, which resulted in thoroughly mixed and chemically altered soils. So using his geologically inspired sense of time and rates of processes, he also rightly imagined that the daily activities of earthworms, multiplied by millions of worms and enough years, changed the very ground underneath his feet in a way so that it, well, evolved.

Ever the good scientist, though, Darwin tested this basic idea through experimentation. His assessment was accomplished through a precise measuring device invented by his son and flat, circular rocks, nicknamed wormstones, which were set out in the backyard of Down House. Based on my visual and tactile examination of the one wormstone that still lies outside of Down House, it looked like a quartz sandstone. However, out of respect for it and its ichnological and historical heritage, I did no other tests of its composition.

One of Darwin’s original “wormstones” (foreground center) placed in a pastoral setting behind Down House. Paleontologist Barbie (just behind the wormstone), who has accompanied me for much field work on the Georgia coast, helpfully provides scale.

Close-up view of wormstone, showing three metal slots set into a central ring and two rods, which provided the datum for measuring change in the wormstone’s depth over time. £10 note (with Darwin’s portrait on the right) for scale.

The experiment was elegantly simple. Using a device invented by Horace in 1870 (illustrated below, and photo here), the surface of the wormstone was measured relative to the height of the surrounding soil surface. This change in relative horizon was discerned by fitting the device on three metal slots that had been added to the edge of a central hole in the wormstone. Metal rods inserted through this same hole were connected to underlying bedrock, ensuring that these would stay stationary as worms churned the surrounding soil. Thus these rods acted as a horizontal datum through which any changes in the ground surface could be compared.

Illustration of Horace Darwin’s “wormstone measuring instrument,” with “K” pointing to where the instrument was placed to contact with the metal rods; the change with each measurement over time between this and “A” (a metal ring) would then show how much the stone had sunk downward. My source of this figure is from an online PDF by the Bromley Partnerships, Discover Darwin: An Education Resource for Key Stage Two, but its primary source is not cited there, and I could not otherwise find an attribution.

Darwin figured that the burrowing activity of earthworms underneath the stone, as well as sediment deposition at the surface as fecal castings, would result in the stone “sinking” over time, becoming buried from below. He was right. Using the wormstone and Horace’s measuring device, he calculated the approximate rate of sinking (2.2 mm/year). This was also a measure of soil deposition, which he attributed to earthworms depositing the sediment through fecal castings. Extrapolating these results further, he estimated that 7.5 to 18 tons (6.8-16.4 tonnes) of soil were moved by worms in a typical acre (0.4 hectares) of land.

Something very important to remember in Darwin’s approach to this study was that he was not just a biologist, but also an excellent geologist, taught early in his career – and later befriended – by one of the founders of modern geology, Charles Lyell. Consequently, he had a long-term view of how small, incremental changes every year added up to big changes over time. Or, to put it in Darwin’s own words (The Formation of Vegetable Mould, p. 6), when he responded to a critic claiming that earthworms were too small and weak to have any large-scale effect on their surroundings:

Here we have an instance of that inability to sum up the effects of a continually recurrent cause, which has often retarded the progress of science, as formerly in the case of geology, and more recently in that of the principle of evolution.

Darwin wasn’t just a quantitative ichnologist, but he also described and illustrated some of the traces made by earthworms, such as their burrows, aestivation chmabers, fecal pellets, and turrets made by their fecal casts. (Much later, in 2007, South American paleontologists described fossil examples of fecal pellets and aestivation chambers from Pleistocene rocks of Uruguay.) Darwin even noted the orientations and species of leaves earthworms pulled into burrows to plug these (p. 64-82), then he independently tested these results with pine needles and triangles of paper (p. 82-90)!

Illustrations of turrets made by fecal pellets of earthworms, in The Formation of Vegetable Mould through the Action of Worms with Observations on Their Habits (1881): from left to right, Figure 2 (p. 107), Figure 3 (p. 124), and Figure 4 (p. 127).

In short, Darwin, through combining his vast knowledge of biology with geological principles, had all the right stuff to make for a formidable ichnologist. Even better, he was keenly interested in the ichnological processes happening just outside his house, and didn’t feel the need to take a long boat trip to watch these processes in some far-off, exotic land. Unknowingly, he was also providing an example of how to do “backyard science” long before this term became associated with cost-effective means for introducing children to nature observation.

All of this marvelous research done by Darwin, culminating in his writing a book at Down House that ended up being one of his most popular, leads me to a bit of a mini-rant, followed by my connecting this science to my homes of Indiana and Georgia, and ending with a message of hope, if I may.

Darwin’s earthworm research epitomized the sort of long-term, DIY experimentation that seemingly only Darwin could have done, and in his day. In contrast, to show how far science has changed since his time, the current profit-oriented business model afflicting modern research universities might have demanded Darwin write a multi-million dollar (or pound) grant to conduct this study. (I suppose the piano would have been the most expensive item on the equipment list, and the wormstones the least.)

Moreover, in this hypothetical scenario, Darwin only could have written such a grant after “pre-confirming” most of his results by publishing a series of research papers. And not just by publishing these papers, but also by making sure they were in prestigious journals, most of which would require expensive subscriptions to read, ensuring that only a small handful of people would read about his work. (A book written for a popular audience? Please.) Had Darwin been a young man, the completion of a 30-year-long study also would have depended on whether he was granted tenure early on. This likely would have been decided by people with little or no expertise in geological processes, earthworms, and bioturbation, but who could certainly count grant revenue and compare journal impact factors.

Fortunately, though, Darwin was independently wealthy, well established as a senior scientist, and never had to worry about tenure or other such trivial matters. Instead, he could just focus on studying his much beloved worms, then think of how to share his vast knowledge of them with a broader audience. Darwin never used the word “ichnology” in his writings, let alone “neoichnology,” and he wrote a book on this topic for natural-history enthusiasts, rather than through a series of research papers published in inaccessible journals. Nonetheless, in his own way, he surely advanced the popularization of ichnology through his slow, deliberate, careful, and imaginative methods, which he combined with a desire to communicate these results to all who were interested.

How does all of this link with Indiana and Georgia? Well, Darwin’s “backyard science” reminded me of how I, like many naturalists of a certain generation, grew up learning about nature through what was in my own backyard. Today I have no doubt that my fascination with the behavior and ecology of insects, plants, and yes, earthworms in my Indiana backyard all contributed to a subsequent desire to do science outside as an adult. To satisfy this urge, I later picked geology as my main subject of study, but also took advantage of my biological leanings by concentrating on ichnology in graduate school. My living in Georgia since 1985 and other serendipitous events then eventually led to my writing a book about traces of the Georgia barrier islands (being published through Indiana University Press). In one chapter of this book, when I introduce earthworms as tracemakers, I made sure to write at least a few pages about Mr. Darwin and his experiments with earthworms. So although Darwin never traveled to Indiana or the Georgia coast, I carried my boyhood and adult experiences of both places in my mind to his former home.

Now here’s the hopeful message (not to be confused with a “hopeful monster“). Lots of field-oriented scientists spend much of their time outside for their research, and many require only modest amounts of money for their studies. So what they have begun to do is side-step the reigning corporate mentality influencing so-called “big science” at universities, while also making active attempts to better connect their research with more people than their academic peers. Through organized efforts like The SciFund Challenge and other crowd-sourcing methods, scientists are seeking small personal donations from the public, allowing them to better focus on their research, rather than spending much time, energy, and angst in writing massive research grants that have little chance of being funded. Thus much like earthworm castings, these  donations add up over time and provide rich, fertile ground for conducting basic science. (OK, maybe not the best metaphor, but you get the point.)

Another facet of this research is the stated commitment of scientists to report their research progress through blogs, then publish their peer-reviewed results in open access journals, which provide articles free for anyone with an Internet connection and curiosity in a scientific subject. All of this means that small investigations with big implications – like Darwin’s study on earthworms – are more likely to happen, and are better assured of reaching a public eager to learn about these sciences, while giving the opportunity for people to witness the direct benefits of their investments.

So how does the Darwin family piano relate to his study of earthworms? Do the southeastern U.S., earthworms, and Darwin’s study of their behavior somehow intersect? In answer to the first question, it’s interesting, and in answer to the second, yes. But an explanation of both will have to wait until next time.

In the meantime, if you go out for a walk later today, pay attention to the ground beneath you, and think of how it reflects an ichnological landscape, a result of collective traces made by those “lowly” earthworms, and how Charles Darwin clearly explained this fact in 1881. For me, it was an honor to stand in the same area where Darwin made his measurements, used his humble instruments, and applied his fine mind; this despite my later realization that I was standing on a new ground surface relative to where Darwin stood. After all, 130 years has passed since his death, meaning the ground had been recycled by descendants of the same earthworms he watched with his appreciative and discerning eyes. All of which makes for a different kind of descent with modification, one that instead reflects an ichnological perspective well articulated and appreciated by Darwin.

Darwin’s “sandwalk,” a walking route behind Down House he often took to help with his thinking, and a visible trace today of Darwin’s legacy as one of the first popularizers of ichnology.

Further Reading

Darwin, C. 1881. The Formation of Vegetable Mould through the Action of Worms with Observations on Their Habits. John Murray, London: 326 p. (A scan of the original book, converted to a PDF document, is here.]

Pemberton, S. George and Robert W. Frey. 1990. Darwin on worms: the advent of experimental neoichnology. Ichnos, 1: 65-71. (Text for article here.)

Quammen, D. 2006. The Reluctant Mr. Darwin: An Intimate Portrait of Charles Darwin and the Making of His Theory of Evolution. W.W. Norton, New York: 304 p.

Verde, M., Ubilla, M., Jiménez, J.J., and Genise, J.F. 2006. A new earthworm trace fossil from paleosols: aestivation chambers from the Late Pleistocene Sopas Formation of Uruguay. Palaeogeography, Palaeoclimatology, Palaeoecology, 243: 339-347.