Articles

Contents: Volume 2, Issue 1 - 15 March 1999

2smISSN 1094-8074

Cover Illustration (close-up of images and information about them)

Editorials and Letters

It's Our Birthday!

The Editors

Paleontology Challenged!

Jere Lipps

Our Readers Write To Us

Articles

Extinction and naticid predation of the bivalve Chione Von Mühlfeld in the late Neogene of Florida

Peter D. Roopnarine and Amy Beussink

Fusulinid succession from the Middle-Upper Carboniferous boundary beds on Spitsbergen, Arctic Norway

Vladimir I. Davydov and Inger Nilsson

Laser confocal microscopy and geographic information systems in the study of dental morphology

Jukka Jernvall and Lena Selänne
PE Note: An errata sheet was attached to the Methods section and to the PDF file.
15 March 1999.

The Thecamoebian bibliography

F.S. Medioli, D.B. Scott, E. Collins, S. Asioli, and E.G. Reinhard

Paleontological databases: Taxonomic decisions

C.W. Stearn and R.T. Patterson, Chairs, GSA Annual Meeting Toronto, October 28, 1998

Conference Proceedings derived from Paleontological Society theme session T-39

Introduction: Easy access to doubtful taxonomic decisions
[Paleontological Society Theme Session, Toronto, Oct. 28, 1998]

Colin W. Stearn

Taxonomy and the security of databases

Roger L. Kaesler, Jill W. Krebs, and Douglas L. Miller

ADAPTS (Analysis of Diversity, Asymmetry of Phylogenetic Trees, and Survivorship): A new software tool for analysing stratigraphic range data

Alistair J. McGowan and Paul N. Pearson

Beyond the cutting edge, electronic publications the 21ST century

Jennifer Pattison Rumford and William R. Riedel

Tribute: H. Alleyne Nicholson -- A great Victorian paleontologist

Colin W. Stearn

Reviews: Books

Technical Books

The Crucible of Creation

by Simon Conway Morris
Reviewer: Stephen A. Leslie

Arthropod Fossils and Phylogeny

by Gregory D. Edgecombe
Reviewer: Jonathan Adrain

The Garden of Ediacara

by Mark A.S. McMenamin
Reviewer: Ben Waggoner

Fossil Art

by A. Seilacher
Reviewer: David J. Bottjer

Charles Doolittle Walcott, Paleontologist

by Ellis L. Yochelson
Reviewer: Loren H. Smith

The Cambrian Explosion and the Fossil Record

by Junyuan Chen, Yen-nien Cheng, and H.V. Iten, Editors
Reviewer: Lisa-ann Gershwin

Popular Books

Dinosaur Summer

by Greg Bear
Reviewer: Martin Anderson

 

Dinosaur Summer
by Greg Bear
Warner Books, Inc.
New York, NY, 1998, 325p
ISBN 0-446-52098-5, $23.00 (US).

Reviewed by Martin Anderson,
1-H Gardenway, Greenbelt, MD 20770, USA.

It's a therapsid-eat-therapsid world that Greg Bear has given us atop El Grande, first brought to our notice in Arthur Conan Doyle's fantasy, The Lost World. There, Doyle introduced us to Professor George Edward Challenger, whose expedition into darkest Amazonia discovered the towering, slab-sided tepui or mesa that hosted, in splendid isolation, the world's last surviving population of dinosaurs.

In Doyle's more innocent, Edwardian days, that was not an unappealing conceit. Why, even in near-contemporary times, on windy nights when dark clouds scud across the moon, folks have been known to whisper of strange creatures said to exist beyond an impenetrable Congo swamp , or across a saw-toothed Papuan range, or perhaps in the unplumbed depths of some Pacific deep.

However, when those depths are plumbed, when we peer down beyond the swamp, or when we cross that range, the limits of our fantasies must again retreat to a more distant venue. All is not lost. If Sasquatch yet eludes us, the coelacanth still persuades that some mysteries may be secreted upon our green earth or beneath its blue seas. Unfortunately, our present experience surely teaches that which we seek in the here-and-now too often becomes mere fairy gifts fading away", in the words of Thomas Moore. With so many of life's greatest mysteries then buried by default in the distant past, what better reason is there to be a paleontologist?

Greg Bear, who would certainly agree, is a science fiction writer of considerable skill and attainment. Much of what he writes is memorable and always a good read. He has prepared himself thoroughly, acknowledging the advice and receiving here the praise of Dr. Philip Currie of the Royal Tyrell Museum. There is an imaginative fidelity to the world he portrays. There are also some extrapolations that, if they do not always persuade, do not detract from this excellent novel.

The story is set in the 1950's. Professor Challenger's long-ago discovery has ultimately culminated in Circus Lothar, which exhibits the last surviving dinosaurs recovered from El Grande. The intervening history has included a set of real and imaginary explorers, some, like Jimmy Angel and Colonel Percy Fawcett, associated with the region. Earlier off-stage assistance was provided by Presidents Coolidge and Hoover. At Circus Lothar, now near bankruptcy, the decision has been made to close down and return the beasts - including a centrosaur, a generic and very nasty theropod named Dagger, an ankylosaur, and some lesser creatures - to El Grande.

Among the real luminaries assembled at Circus Lothar in Boston are John Ringling North, John Ford, Ray Harryhausen, (still alive to praise the book), and the producers of King Kong, including the wealthy Merian Cooper, whom we shall meet again. Joining them are Anthony Belzoni, a National Geographic photographer, and his teen-age son Peter, until now a student at New York's George Edward Challenger High School, named for the great explorer, surely an appropriate prep school for the forthcoming adventure.

And a rousing adventure it is. The expedition is carefully planned and well-engineered. All the creatures are transported as securely as possible from circus to ship, by ship through the Atlantic to the Orinoco River, and up the river to Puerto Ordaz. Here the beasts in their cages are off-loaded to barges for further transport to the railroad at San Pedro de las Bocas and, from there, by train to a railhead within sight of El Grande.

Throughout, there are twin menaces looming. The theropod raptor Dagger - a horror with the eyes and charm of a basilisk - has been oozing a murderous, subliminal threat to all within view, his angry assaults threatening the integrity of his cage. Sharing the top of the food chain, the local Venezuelan military, barely obedient to the Caracas authorities, regards the outsiders of the expedition with unconcealed and uncooperative distaste.

The last leg, by truck, proceeds by dizzy switchbacks to the mile-high top of Pico Poco, an El Grande outlier, also discovered by Professor Challenger. During earlier years of exploration and collection, a counter-balanced steel swing bridge had been constructed to permit access from Pico Poco across the hundred-foot wide, mile-high chasm to the top of otherwise unclimbable El Grande.

Except for Dagger, the passage of all the animals to El Grande proceeds exactly as planned. With Dagger, a grand melee ensues when he finally escapes his cage. Peter and a few others, including the film crew, flee across to El Grande, while Dagger's weight collapses the span slowly enough for his escape back to Pico Poco. Injured, Dagger awaits certain execution by the panic-stricken Venezuelan soldiers.

Peter and his companions are trapped across the divide upon the mesa with its strange and deadly population. They see great and awful wonders and barely survive from one danger to another as they desperately await rescue. There is, of course the expected cast of Jurassic-Cretaceous fauna, to which Greg Bear has added his version of 65 million years worth of evolution.

One frightening new inhabitant is Stratoraptor, the gigantic, flightless, feathered death eagle, who is systematically exterminating the raptor population of El Grande. Save for an unhatched egg in an abandoned nest by a lake shore, poor unhappy Dagger would have had neither home nor relations to return to, had he survived.

Flying an amphibious PBY on loan from the U.S. Navy, Merian Cooper, of King Kong fame, arrives at a plesiosaur-stocked lake in the nick of time to rescue our lost party, their cameras, and their film as they struggle with a death eagle by the lake shore.

This grand story is profusely and dramatically illustrated by Tony DiTerlizzi. It is a wonderful book for an older child, perhaps of high school age, and certainly an entertaining one for readers of any age.

Copyright: Palaeontologia Electronica, 15 March 1999

 

 

Martin Anderson
1-H Gardenway
Greenbelt, MD 2077
US
This email address is being protected from spambots. You need JavaScript enabled to view it.

Beyond a geologist daughter and a paleontologist son-in-law, Martin Anderson claims no particular expertise in these matters. He is a retired private investor, though not an inactive one; and his education includes an electrical engineering degree and a master's in biology. He is a member of Sigma Xi and the Institute of Electrical and Electronics Engineers.

 

 

The Cambrian Explosion and the Fossil Record
edited by Junyuan Chen, Yen-nien Cheng, and H.V. Iten,
Bulletin of National Museum of Natural Science, Division of Collection and Research, National Museum of Natural Science, 1, Kuan-chien Road, Taichung, Taiwan, December 1997, 319 pages
ISSN 1015-8448.

Reviewed by Lisa-ann Gershwin,
Department of Integrative Biology, University of California, Berkeley CA 94720, USA.

"Wow!" was my first reaction, and it will certainly be yours as well. This multidisciplinary book, which is the product of the Cambrian Explosion Symposium in Nanjing, China in April 1995, brings together 16 papers on everything from algae to sponges to chordates, and from isotopes to taphonomy to geochemistry. There is truly something for everyone in this volume. But possibly the number one reason to covet this book is the huge collection of color photographs of some of the world’s most stunningly preserved fossils. The focus is on the fauna, with almost 200 pages devoted to descriptions of new taxa, reinterpretations of old taxa given new preservational information, and hypotheses about form and function.

The book begins with "The Meaning of the Cambrian Explosion" by Dolf Seilacher, which sets the stage with a review of some prevailing ideas in Precambrian studies and some of the main innovations of the Cambrian fauna (e.g. trace complexity, skeletonization, bioturbation, the diversity of trophic guilds).

The primary paper of the volume (Biology of the Chengjiang fauna, by Chen and Zhou) covers nearly 100 pages and much of the "wow!" in glorious full-color photographs. The magnificent preservation, biological diversity, and sheer quantity make this a collection of extreme importance. The paper presents well over 100 of the most spectacular specimens from the collection of 15,000 recovered so far. I could write endlessly about the beauty of the collection, but suffice it to say that I cannot imagine anyone will be disappointed. With that said, however, let me now highlight a few oversights that make this paper a little difficult to read and a little bit annoying. Firstly, the format of the paper was confusing, as I repeatedly found myself flipping back and forth between the two complementary sections, "fossil evidence of disparity" and "systematic paleontology" in order to glean all the information about any given taxon, some of which were never actually treated after their introduction. Secondly, the figures would have benefited substantially by the inclusion of scale indications. For some taxa, approximate sizes are given in the text, but not for all. Quite frankly, I felt a bit irritated at having to work so hard to find the relative sizes - that is the author’s job, not the reader’s. Thirdly, I was a bit put off by some of the conclusions in this paper, as I felt that they lacked a clear progression of reasoning. I found myself wanting to accept the ideas of Chen and Zhou, but unable to arrive at the same conclusions given the information presented. For example, their interpretations of two ctenophores left me quite puzzled. Both were interpreted as having a membranous skirt, although I found it difficult to agree from the facts provided. Furthermore, one of the genera was classified into the Ctenophora based on its possession of aboral papillae despite its tetraradiate symmetry and absence of comb rows. However, Chen and Zhou failed to mention that numerous species of jellyfishes have aboral papillae and are, of course, tetramerous and lacking comb rows. In another example, their restoration of a new algal genus left me similarly puzzled. They picture it as a bubble with numerous filaments hanging down, but fail to explain this construction in the text. I was unable to find evidence of a bubble in the photographs. Fourthly, I never did come to terms with Figures 76 and 77, which are supposed to be different as indicated by their specimen numbers, but look very similar to me. All this left me wondering what additional mistakes I had failed to notice. Despite these annoyances, I still learned many things from the paper and gained a deep appreciation of the Chengjiang collection through the vast amount of information presented.

In a paper as similarly stunning as the Chen and Zhou article, the affinity of Yunnanozoon, previously incertae sedis, seems finally convincingly interpreted as a chordate. Chen and Li provide not only many excellent color photographs, but also a good explanation of their comparison of Yunnanozoon with the Recent chordate Branchiostoma. However, like the Chen and Zhou paper, this one fails to consistently provide a sense of scale in the figures, but also adds the annoyance of often referring to specimen numbers rather than figure numbers in text discussions. No doubt to be the topic of much future discussion, this paper proposes the powerful hypothesis that a Yunnanozoon-like ancestor gave rise independently to the sister groups Tunicata, Cephalochordata, Conodonta, and Agnatha. Unfortunately, only a single paragraph was devoted to this idea, with only the most casual reasoning. I would like to take Chen and Li to task on this for my gut instinct is that they are onto something worthy of much more explanation.

I must not neglect a few other papers of specific noteworthiness. In one, Chuang reports on an interesting study of the functional morphology of Recent brachiopod ridges, and their usefulness in the identification of fossil taxa. However, I was left wondering whether this sort of non-taxonomic work actually constituted a legitimate species description, as mentioned in the abstract, or whether this created a nomen nudum. In another, Babcock and Chang give a fascinating interpretation of the taphonomy of Naraoia spp. through disarticulation experiments on the Recent horseshoe crab (Limulus polyphemus). While I was particularly surprised to learn that most Limulus specimens "remain nearly complete for at least two years" under anoxic and undisturbed conditions, it would have been helpful to know the number of replicates used in their various experiments. Possibly my favorite paper, next to the one by Chen and Zhou, was Zhu’s 38-page report on the trace fossils across the Precambrian-Cambrian transition, and their implications in defining the Pc-C boundary. A good review of the different types of traces is given, followed by an interesting discussion of trends in complexity through the Pc-C transition. Although this paper suffers from issues of scale and spelling, I found it to be particularly well constructed and well reasoned.

The remaining papers are certainly worth reading. Zhang et al. report on stable carbon isotope changes across the Neoproterozoic-Cambrian boundary. Tang et al. present their SEM work on resolving the nature of the grains in granular phosphorites, accompanied by 27 black and white images; Nedin concludes from laboratory findings that early mineralization is controlled by oxygen availability and pH. Siegmund discusses phosphogenesis as enhanced by microbial organisms. Zhang et al. review the distributional and geochemical implications of volcanic metabentonites. Popov and Zhang describe the distribution of calcareous algae, while Popov describes their diversity; Li details the systematics and diagenesis of 6 species of endolithic algae, with 31 photographs. Yin provides 10 color photographs and an additional 10 black-and-whites to accompany the study on acritarch biostratigraphy across the Precambrian-Cambrian transition. And Qian proposes a revised classification of the hyoliths based on 7 chronostratigraphic stages.

Because of the importance of the Chengjiang collection and the magnificent presentation of it in this volume, without doubt many of the papers in this book will be the subject of much discussion in the years to come. I heartily recommend this book to both professionals and students, for its broad scope will certainly appeal to a variety of interests. Overall, it takes the reader on a fantastic journey of wonder and amazement through the various biological and physical aspects of the Cambrian Explosion.

Copyright: Palaeontologia Electronica, 15 March 1999

 

 

Lisa-ann Gershwin
U.C. Museum of Paleontology
University of California, Berkeley
USA
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Lisa-ann Gershwin is pursuing a PhD at UC Berkeley, and is currently on a Fulbright Fellowship studying living and fossil jellyfishes in Australia. Her main interests seek to understand the evolution of radial symmetry by studying its variability in Vendian taxa as well as Recent cnidarians, echinoderms, and silicoflagellates. However, she devotes much of her spare time to studying the broader aspects of early metazoan evolution. She was awarded Howard Hughes fellowships in both 1995 and 1996 for her work, and she is a member of Sigma Xi and various other academic and professional organizations.

 

 

Charles Doolittle Walcott, Paleontologist
by Ellis L. Yechelson.
The Kent State University Press, Kent, OH 44242, 1998, 510 pages,
ISBN 0-87338-599-3, $49.00 (US).

Reviewed by Loren H. Smith,
Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA.

Most college-level texts in the fields of historical geology, evolutionary biology and paleontology present a skewed view of earth history. The geologic time scale generally consists of the Phanerozoic divided at various levels of detail, with a sliver of the “Precambrian” slapped on the bottom, not to scale, and generally without an indication of scale break ( e. g., the timescale). Occasionally this bias is addressed (usually in conjunction with a pithy metaphor demonstrating the relative paucity of time represented by the Phanerozoic), but given the intended audiences for most of these texts, the Phanerozoic is ‘where it is at’ and emphasis is duly placed there by the various authors. Of course, this is not to imply that the bias is intended to slight the Precambrian, for certainly it is difficult to nearly impossible to understand the last 600 million or so years of earth history without a firm understanding of the preceding three billion plus years of the Precambrian.

Readers of the new biography of Charles Doolittle Walcott may be disappointed that it essentially reverses the bias inherent in most representations of geologic time. The work ends in 1907, twenty years before his death, but only two years before the discovery of the Burgess Shale. However, any disappointment in this choice of stopping place should be well counterbalanced by the great detail with which Yochelson has set the stage for the better known events of Walcott’s life. In all truth, without this meticulous account of the early years it is likely that Walcott would be doomed to remain a fairly one dimensional character as the man who discovered and described the Burgess Shale. As the Precambrian is so much more than stromatolites and banded-iron formations, Walcott was so much more than the Burgess and its remarkable biota.

The 468 pages of text devoted to the first 57 years of Walcott’s life are a detailed catalog of personal, professional, political, financial and scientific events. Much of the history recounted is supported by the voluminous diaries that Walcott kept religiously throughout his life. In a single paragraph we discover Walcott the romantic, Walcott the astute politician, Walcott the paramount administrator, and even Walcott the paleontologist. The amazing journey taken by an itinerant farmer to the pantheons of American and international science continually astounds. Although many of Walcott’s predecessors and contemporaries also pulled themselves up by their bootstraps (Schuchert being another prime example), there are few comparable rags-to-riches stories of such scope. This biography allows us to ponder what made Walcott tick. How did an avid amateur collector who never gained a high-school diploma rise to the highest ranks of academic and professional life during this period of human history? What were the origins of his amazing political acumen? How did Walcott’s personal background affect his scientific views? The level of detail now available allows these and a myriad of other questions to be answered at long last.

If there is one minor difficulty with the biography, it is that little connection is made to the major events late in the life of Walcott. Again, as the Precambrian sets the stage for the Phanerozoic, Walcott’s early life is an important preamble to his directorship of the Smithsonian and discovery of the Burgess shale. The reader is left hanging at the end, with little sense of what is to come, or how to bridge the wealth of knowledge about Walcott’s ‘early’ life with the better known achievements yet to transpire. The Burgess Shale biota is not even mentioned in the text, and no references are made to more extensive discussions of its historical and paleontological importance.

All in all, however, Charles Doolittle Walcott, Paleontologist, presents a richly detailed exposition of the life of one of America’s most important practitioners of science. Slowly the importance of what has traditionally been viewed as ‘prehistory’ is being realized.

Copyright: Palaeontologia Electronica, 15 March 1999

 

 

Loren H. Smith
Assistant Professor of Biology
University of Southern California
Los Angeles, CA 90089-0371
USA
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Loren H. Smith grew up in Williamsville, New York, approximately 200 kilometers along strike from Walcott's early stomping grounds. His interest in paleontology was sparked by a sixth-grade field trip to the Devonian strata exposed along the shoreline of Lake Erie near Derby, New York and the famous 18-mile creek localities first documented by Grabau. His interests in trilobites have extended back to the Cambrian; he studies the relationship between microevolutionary processes and macroevolutionary pattern during the Cambrian radiation.

 

 

Fossil Art
by A. Seilacher,
The Royal Tyrell Museum of Palaeontology, Drumheller, Canada 1997, 64 pages, $10.00 (US).

Reviewed by David J. Bottjer,
Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089-0740, USA.

Art and science. To a lot of people they don't sound like they should mix. And, yet, we know that to many people fossils have aesthetic qualities that cause them to be prized and collected. In a blend of art and science, Fossil Art is the book which Dolf Seilacher has produced to accompany his traveling exhibit of the same name.

Every once in a while an individual comes along who is able to bridge the gap that typically exists between art and science. Audubon, that great nineteenth century popularizer of American birds, was able to portray the aesthetic qualities of birds in his art so successfully that today many images from his great double-elephant folio are among the most prized of natural history prints. His modern legacy is as one of America's greatest artists. However, as pointed out by Gerald Weissmann in a recent essay entitled "Darwin's Audubon" (in Weissmann 1998), Audubon coupled his art with scientific observations that in his lifetime made him a member of many learned societies, and many of Audubon's observations were used by Darwin in his writings on evolution.

Those who know Dolf Seilacher have always been aware that he is interested in design and the aesthetic values of fossils. His monumental contributions to the understanding of functional morphology - the design of organisms - are testament to these interests. He is a visual thinker, as anyone discovers who has studied the wonderful illustrations in his papers. And, we have always known that he was drawn towards deciphering the clues left by the behavior of organisms in sediment - trace fossils.

So, it comes as no surprise that Seilacher has spent some of his Crafoord Prize money to try and cross that no-man's land between art and science. This has resulted in his development of a traveling exhibit displaying primarily the artworks of earth's invertebrates, as left in their record of trace fossils, and as selected and interpreted by Dolf for their aesthetic qualities.

Like Audubon, Seilacher has also mixed a scientific message in with his artistic display. This message concerns much of his vision of what life was like at the Proterozoic-Phanerozoic transition, as metazoans were initially evolving. In Fossil Art he outlines these ideas in a clearly written Introduction. Further elaborations are made in the excellent line drawings he provides to accompany many of the photographs of the casts of large bedding surfaces which form the core of the exhibit. The main point of his message is encompassed in his illustration entitled "Agronomic Revolution" (Figure 1). Seilacher has been a champion of the view that in the Proterozoic, before extensive bioturbation, most subtidal environments were covered with microbial mats that provided a layered structure to the sedimentary component of ecospace in which early metazoans evolved. Thus, these earlier sea-floor environments he terms "matgrounds" were transformed to "mixgrounds" in the early Phanerozoic with the evolution and development of bioturbat organisms (Figure 1).

In contrast to carbonates and stromatolites, it has always been tough to demonstrate that microbial mats typically covered siliciclastic sea floors during the Proterozoic and the Proterozoic-Phanerozoic transition. Seilacher, and his colleagues such as Friedrich Pflüger, have decided to tackle this problem through a complex unraveling of what seem to be ordinary sedimentary structures. An example of this approach is the analysis of palimpsest ripples (Figure 2): where two sedimentation events have created ripples leaving evidence that the sediment surface after the first event was coated with a microbial mat or film. Palimpsest ripples are named after medieval murals in which new pictures were laid over old ones so that now the earlier images can be reconstructed through removal of the later ones. In the top example (Figure 2) the starved secondary ripples overlie the perfectly preserved primary ripples, indicating that an erosion-resistant surface (such as a microbial mat) covered the primary ripples. In the middle example (Figure 2), Seilacher has deciphered the following sequence:

  1. a secondary sedimentary event completely buried the underlying primary ripples;
  2. subsequent formation of ripples in the overlying bed led to erosion in the secondary ripple troughs of the underlying ripple crests; which
  3. left erosional scars (seen here as casts), with a scoop-shape indicative of an erosion-resistant surface (microbial mat) covering the primary ripples.

In the bottom example (Figure 2), Seilacher postulates that the presence of a slimy microbial film on the lower primary ripples led to a distinctive pattern of load-casting when the secondary sedimentary layer was deposited.

Surely if siliciclastic sea floors were covered with microbial mats, early metazoans must have evolved strategies to exploit this food resource. One such strategy is presented on another slab in the exhibit (Figure 3) which shows arcuate sets of scratches on a Neoproterozoic sediment surface, interpreted to have been made by the radula of a large slug-like mollusc. Seilacher suggests that this mollusc was likely similar to Kimberella (Figure 3), recently described (Fedonkin and Waggoner 1997) from similarly-aged strata in the White Sea area of Russia. Not only do the scratch marks indicate a concentrated food resource (such as a microbial mat) at the sediment surface, but the absence of a trail by their slug-like producer indicates that some feature, such as a mat, was firm enough to allow the body to cross this surface without leaving a trace.

Mats not only provide a concentrated source of food on the sediment surface, but the presence of decomposing mats below the surface would also create a potentially enticing layered trophic resource. Seilacher has postulated that the mining by deposit-feeders of these decomposing layers, a strategy that he terms "undermat miners," was a common one when sea floors were characteristically matgrounds. In another example from the exhibit (Figure 4) we see a slab covered with the trace fossil Oldhamia, created in an Early Cambrian deep-sea setting by undermat miners. As shown in Figure 4, this strategy persisted in the deep-sea for some time into the Paleozoic. This occurred because the deep sea served as an environmental refuge for matgrounds. Ultimately, however, more extensive bioturbation and mixgrounds became the predominant mode in deep-sea sedimentary settings, as it already had become in shallower environments. This non-actualistic approach to analyzing organism-sediment relationships during this time period is only just coming into its own. A variety of other geobiologists are also delving into this field.

The examples I have discussed constitute only a small part of the thirty-six cast bedding planes from the exhibit which are described in Fossil Art. Seilacher presents each of these additional bedding planes both as artwork and as the basis for an intriguing scientific story. Many more of the slabs relate to early metazoan environments and lifestyles, but there are also a number of examples from younger intervals in the geologic column. Each of the slabs and their analysis highlights the uniquely "Seilacherian" approach of taking an anomalous individual sample or specimen, teasing-apart the reasons for those anomalous features, and using the results to build more general statements about the ancient Earth and its life. Like Audubon, the message truly is one of both art and science.

The exhibit was originally created by Seilacher and his preparator, Hans Luginsland, at the forcer's long-term home, the Geologic Institute of Tübingen University in Germany. It has recently been touring North America under the auspices of The Royal Tyrrell Museum of Palaeontology, Fossil Art exhibit, in Drumheller, Alberta. Unfortunately, this beautifully-produced "Fossil Art" book is not widely available, but it can also be purchased from the Tyrrell Museum by contacting Janice Leonhardt.

See References.

Copyright: Palaeontologia Electronica, 15 March 1999

 

 

David J. Bottjer
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Dave Bottjer did his undergraduate geology major at Bryn Mawr College (1973), and received his Ph.D. from Indiana University in 1978. Since 1979 he has been at the University of Southern California, where he is now Professor. His interests lie in the realm of Phanerozoic paleoecology and paleobiology, and his current research is aimed at unraveling ecological settings at the beginning of both the Paleozoic and the Mesozoic. Here he is shown on a Lower Cambrian bedding plane which, to the right, has large grooves made by an early metazoan bioturbator, and thus provides a snapshot during the beginning of the agronomic revolution.

 

 

REFERENCES

Fedonkin, M.A. and Waggoner, B.M. 1996. The later Precambrian fossil Kimberella is a mollusc-like bilaterian organism. Nature, 388: 868- 871.

Weissmann, G. 1998. Darwin's Audubon: Science and the Liberal Imagination. Plenum, New York.