Middle Cambrian Trilobites of the Czech Republic - A Bohemian Rhapsody

       

Fall foliage on the Berounka River. Jince, Czech Republic.

The Berounka River cutting through the Litavka Valley near the town of Jince.

       Sometimes the work of a single scientist can change the perceptions of the entire world. Those efforts -- whether or not they are fully recognized, or even acknowledged, during their lifetime -- can often lay the groundwork for a veritable “revolution” that may occur over subsequent years, decades, or even centuries. Charles Darwin certainly placed himself in such a position following the publication of his historic Origin of Species in 1859. So did Albert Einstein with his landmark efforts in theoretical physics during the first half of the 20th century. Come to think of it, so did the likes of Thomas Edison, Marie Curie, Nicolaus Copernicus and Galileo Galilei. And so did Joachim Barrande -- admittedly, to a somewhat less dramatic extent. 
       During the middle years of the 19th Century, this self-taught French naturalist spent decades collecting and studying the trilobites of what was then known as Bohemia and is now the Czech Republic. At a time when activities such as geology and paleontology were often viewed as mere “recreations” designed to keep the affluent occupied, Barrande proved that supreme dedication to one's scientific goals was far more than an avocation -- it was a noble and important life's pursuit. Indeed, Barrande spent nearly 40 years exploring the roughly 200 square mile area that comprises the various sedimentary formations of central Bohemia, a region that is now aptly recognized as the Barrandian Fossil Assemblage. It is an incredibly rich paleontological strata, featuring no less than 50 prime Paleozoic outcroppings that date from the Middle Cambrian to the Upper Devonian. It was in this lush area dominated by rolling hillsides, winding rivers and verdant farmlands that he discovered, analyzed and subsequently named over 500 different fossil species. 
      The compendium of his career work, which began emerging in 1852 as the richly illustrated volume, Systeme Silurien du Centre de la Boheme, helped revolutionize the role that paleontology played in scientific studies. In fact, the wonderfully detailed trilobite drawings revealed within that book helped open the eyes of many to the wonders of the Paleozoic world. And while none of the fossils he presented were actually Silurian in age, such details mattered little when compared to the impact that Barrande's work had upon the planet's intellectual community. 
       For decades paleontologists had been treated as the proverbial red-headed stepchildren of scientific society, with their work often ridiculed, overlooked or simply ignored by those involved with more “important” research. But following in the wake of Sir Roderick Murchison's groundbreaking investigations of English Silurian systems, Barrande's writings took the study of fossils to previously unimagined levels of acceptance. Apparently, the depth and scope of his research also served as an important influence upon Darwin himself, who cited Barrande's pioneering efforts within his own writings. Rather ironically, throughout the latter years of his life, Barrande was a vocal proponent of Georges Cuvier's then-popular “catastrophe” theory of change (which postulated that short, violent events altered the face, as well as the fauna, of the planet), a concept that ran directly opposed to Darwin's own evolutionary beliefs.
     “Barrande was a very interesting individual,” said Pavel Dvorak, an amateur paleontologist based in Prague who has spent many years exploring the Barradian horizons. “He was originally trained as an engineer, but when he was still a young adult he became connected to the French royal family as a tutor. When the king was forced to abdicate in 1830, he followed them around Europe, eventually ending up in Bohemia. Within a year of moving to Prague, he had launched his own fossil studies, though no one appears certain as to what drew him to that particular field of study in the first place.”
       Much of Barrande's work with Bohemian trilobites was conducted in a broad expanse of 510 million year old sedimentary outcrops, the majority of which have since become categorized as the Jince Formation. It is a fossil-laden strata where a peculiar layer cake-like sedimentation apparently reflects the shifting climactic conditions that impacted the region during the Middle Cambrian. Throughout the Jince, bands of rich, fossiliferous layers are dramatically interspersed with generally barren strata, a phenomenon that paleontologists suggest indicates the area's continual changes over a 20 million year period from a thriving, deep water marine environment into a less stable, and less habitable shallow-water estuary… and then back again.  And the ever-shifting tides of Cambrian seas seemingly weren't the only natural phenomenon that helped create the Jince's unique paleontological pedigree. In contrast to many world-renowned fossil formations where the fauna and flora indicate that their surrounding environment was semi-tropical, half-a-billion years ago, the waters that covered what is now the central Czech Republic were decidedly cool. 
      That is a fact many paleontologists believe helps demonstrate the adaptability of the trilobite line to widely divergent climatic and oceanic conditions -- even fairly early in their evolutionary development. Indeed, these unique environmental conditions nurtured the emergence of an incredibly diverse trilobite stock. More than 50 different species of these ancient arthropods appear in the Jince Formation, most featured in three distinct trilobite orders -- Redlichiida, Ptychopariida and Agnostida. The more common species include Paradoxides gracilis, Ellipsocephalus hoffi, Conocrype cirina and Hydrocephalus minor. Rare species include Acadoparadoxies sacheri, Jincella prantili and Perneraspis conifrons. The area's trilobites are most often found in a dark, chocolate-colored mudstone that has been slowly exposed along certain outcrops as the Berounka River cuts through the Litavka Valley near the town of Jince. In fact, that town is so proud of its world-renowned paleontological distinction that it has adopted an illustrated rendition of a trilobite as part of its city flag. 
       When pried out of the area's fossiliferous Middle Cambrian layers, and broken apart by chisel and hammer, the larger trilobites (which include Paradoxides species up to eight inches in length) usually emerge in rather flat, positive/negative “splits”, while many of the smaller trilo-types retain much of their original three-dimensional convexity. Though complete specimens have never been particularly prolific at any of the Jince sites, more than two centuries of digging in the area's rich outcrops has produced perhaps the most complete and detailed trilobite assemblage found anywhere on earth. When paleontologists compare this amazing collection to strikingly similar Middle Cambrian trilobites discovered in other parts of the world, including those of Eastern Canada, Sweden and Morocco, they provide a foundational building block for one of the most important scientific theories of the last century, Plate Tectonics. That theory suggests how the planet's various continental masses have broken apart over time and subsequently shifted their global position while slowly sliding over the earth's molten core.
       “The trilobites of the Jince Formation are among the keystone specimens of the world,” explained Bill Barker, an American fossil dealer who has dealt extensively with Middle Cambrian trilobites. “Many Middle Cambrian locations feature material -- especially Paradoxes -- that are contiguous with the trilobites first found and described by Barrande while he was working in central Bohemia. That effort has served as one of the keys for our understanding of how the dynamics behind Plate Tectonics actually occur. But no other place has an impressive inventory of Cambrian material equal to that of the Jince -- digging there has been done at sporadic intervals for centuries, with the sheer number of trilobites found being quite impressive.” 
     The world's awareness of Bohemian trilobites dates back nearly 250 years -- to 1770, in fact, when a certain Professor Zeno first published a report on various fossils (including a Dalmanites pygidium) he had discovered while exploring throughout the Prague region. Various subsequent manuscripts made their appearance throughout the 19th Century, with these either directly or indirectly referencing the area's paleontological treasures. These volumes were, of course, highlighted by Barrande's own work. Yet for all the attention drawn to the Paleozoic outcrops of Bohemia due to that historic effort, the world's opportunity to experience hands-on contact with many of the region's more exotic trilobite species only began in earnest following the fall of communism back in the mid-1980s. 
     Prior to that time, the inherently secretive nature of what was then the Soviet “satellite” nation of Czechoslovakia prohibited the exportation of the nation's natural resources… including fossils. At times, there even seemed to be a government-imposed ban on scientific thought -- let alone information -- escaping the nation's boundaries. Even during these “dark ages”, however, a few key trilobite specimens -- mostly of semi-complete Paradoxes, managed to filter out of the region. At the same time copies of Barrande's original manuscripts could still to be found in most museum reference rooms, and photographs of many unusual Bohemian trilobite species remained available through certain European collectors. For more than 40 years, however, direct access to the nation's rich abundance of trilobites was strictly limited by government edict. 
      It was rare indeed, for a Western scientist to be provided the opportunity to wander through the extensive Barrandian collections held within the confines of Prague's renowned National Museum of Natural History. And for far too long, virtually all Czech fossil material was considered “off limits” to the world's paleontological community. However, once the walls of communism came tumbling down, both literally and figuratively, and the doors of the Czech Republic were thrown open to outsiders, the incredible beauty, diversity and significance of Bohemian trilobites began to once again be fully appreciated by collectors and scientists around the globe. 
      While in recent years new laws have been implemented by the Czech government, which have served to restrict digging in the Jince Formation -- which is now viewed a National Historical Site - access to museum collections, as well as additional scientific fieldwork, has greatly increased our knowledge of the entire Barrandian laggerstate.  Books, pamphlets, DVDs and internet sites have recently appeared on the world market, all presenting some aspect of either the inherent charm or the scientific importance of the nation's rich Middle Cambrian trilobite reserves.
        “There has definitely been a reawakening of interest in this material,” said a representative of the Prague National Museum. “Many in today's generation don't remember the time when it was difficult for even Czech scientists to study our own trilobite resources. These days it is encouraged -- not only for us, but for scientists from around the world, as well.”
      Now more than 150 years after Barrande's volumes first made the entire scientific community aware of the incredible diversity contained within Bohemia's fossil outcrops, there seems to be ever-increasing interest in both his writings, and in the trilobites themselves. In 1999 -- the year that celebrated the 200th anniversary of his birth -- a limited edition reprint of Systeme Silurien du Centre de la Boheme was issued by Prague's National Museum of Natural History… and almost immediately sold out. While many of the trilobite names originally attributed by Barrande have since been changed, and though he made a fundamentally incorrect assessment that the materiel he was studying was Silurian in age rather than Cambrian and Devonian, the magnificence of his illustrations, as well as the detail of his work, remain unchallenged. 
      Clearly Joachim Barrande stands on a lofty plateau, one reserved for only the most visionary of scientific explorers. His studies may never have attained the earth-changing heights of a Darwin or Einstein, yet without his pioneering efforts, the science of paleontology, as well as the theory of Plate Tectonics, would perhaps never have garnered the degree of credibility and notoriety they currently enjoy. 
      “Every time I hold a trilobite from the Czech Republic, whether it is a small Ellipsocephalus or a large Paradoxides, it's hard not to think of Barrande,” said Dvorak. “How fortunate he was to be the man who first found and studied such amazing specimens, and how fortunate we now are to have his work to learn from and enjoy.”

Click here for the Gallery of Jince Trilobites

The flag of Jince, Czech Republic, featuring a trilobite in the center. The rectangular flag is composed of three horizontal bars: the top blue, the center black, the bottom red.

Flag of Jince, Czech Republic, featuring a trilobite.