fossils

June 9, 2021 by wpengine

Student of the World; Part 2: Stearns and Bayet

by Joann Wilson and Albert Kollar

“His [Frederick Stearns] love for that which was beautiful and useful, led him to collect a vast amount of material covering so many fields of human effort…”

Detroit Free Press, January 15, 1907

Fossils pass through many hands. Some hands hold discoveries, some buy and sell, others study and organize. Behind every fossil is a story and hopefully, for those in museum collections, a specimen label. With luck, the geology and paleontology of the label script is accurate. Beginning with the creation of the first color geological map by William Smith in 1815 and the subsequent organizing of the Geologic Time Scale in 1823, paleontologists worked to validate stratigraphy by collecting and describing new species from exposed strata in Europe and North America. It was not until the publication of Charles Darwin’s The Origin of Species in 1859 that paleontological work shifted to include studying evolution as documented by fossil evidence.

Today we understand that many hands aided fossil discovery, often in anonymity. Thanks to technology and through a focus shift to the individuals behind the specimens, we can now provide a fuller picture of the past that acknowledges the roles of collectors, dealers, indigenous cultures, women, quarry workers, and all who aided in the pursuit of fossils.

In the basement of Carnegie Museum of Natural History, behind a set of gray steel doors in the Section of Invertebrate Paleontology, is an astonishing assembly of archival documents from the Bayet Collection. Andrew Carnegie made front page news in 1903 by purchasing an estimated 130,000 fossils from Ernest Bayet of Brussels. Along with the fossils, the museum also received hundreds of documents written primarily in French, German, and Italian. Most of it has remained untranslated, until now.

Thanks to volunteer Lucien Schoenmakers of the Netherlands, details of fossil trades and purchases from over 100 years ago provide links to narratives that have yet to be told. Join us as we start the journey. Our series, which began with an examination of correspondence between fossil collector Frederick Stearns and his client, Bayet, continues here with a deeper profile of Stearns.

Frederick Stearns, date unknown. Permission of the University of Michigan Stearns Collection.

Frederick Stearns of Detroit was a man not born into wealth, but with a passion for education, art, and science. His early life revolved around diligence, not fossils. Born in Lockport, New York in 1831, Stearns quit school at age 14 to find a job. Within a year, he found work as an apprentice to a pharmacist in Buffalo, New York. Of his early life, he later said, “one of my earliest memories is looking into the windows Dr. Merchant’s Gargling Oil Drug store and wondering at the mystery of the white squares of magnesia and the round balls of chalk.” Eventually, Stearns moved to another pharmacy, and became partner, but he was not convinced that Buffalo, New York was his ticket to success.

On a frosty New Year’s Day in 1855, Stearns, newly married and just 24 years of age, crossed the frozen Detroit River by foot to start anew. Of that period, he later said, “little money, fair credit, high hope.” He opened a retail pharmacy in Detroit. To reach customers, he made short trips to the surrounding area, leaving samples of his products. Over time, his business expanded to the manufacture of pharmaceuticals. In 1877, he made history by installing the first telegraph line in the city of Detroit. But despite the success, Stearns dreamed of the education lost to him when he left school at the age of 14. In 1887 at age 56, he turned the business over to his sons and he began to travel the world. Over the next twenty years, he collected many items, including fossils.

William Smith’s 1815 Color Geological Map.

Stearns pursuits led him to Africa, Europe, and Asia. In the late 1800’s, a voyage to Japan required weeks of travel as compared to a current 14-hour flight from New York to Tokyo. In the early 1890’s, Stearns travelled to Japan twice for the purpose of studying mollusks and other marine life. In a book published in 1895 titled, “Catalog of the Marine Mollusks of Japan,” Stearns credits Japanese fisherman Morita Seto for assisting in the collection of over “1000 forms of marine life.”

But Stearns interest did not stop with mollusks. He also collected fossils, art, and musical instruments. His collection of musical instruments at the Stearns Collection of Musical Instruments at the University of Michigan, in Ann Arbor Michigan, is considered one of the finest in the world.

For a short time, Stearns also collected fossils. Between 1888-1889, he wrote two letters to Ernest Bayet about a trade deal. Stearns first letter offers a clue as to how they met. Both men appear to have known fossil dealer Lucien Stilwell of Deadwood, South Dakota. The trade between Stearns and Bayet did not go smoothly, but it does have a happy ending.

Stearns was a student of the world until the very end. In 1907, just days before he was scheduled to sail for Egypt, he became ill and died. At his passing, the Detroit Free Press wrote, “A remarkable phase of Mr. Stearns’s activities as a collector was their diversity… and all of this for the simple love of learning things that he might tell them to others without price.”

Many thanks to the generous contributions of Carol Stepanchuk, Outreach and Academic Projects at the U-M Stearns Collection of Musical Instruments Lieberthal-Rogers Center for Chinese Studies and Joseph Gascho, Associate Professor at the University of Michigan School of Music and Director of the Stearns Collection of Musical Instruments. Many thanks to volunteer Lucien Schoenmakers’ ongoing effort to translate archival Bayet documents written in French and German.

Joann Wilson is an Interpreter in the Education Department at Carnegie Museum of Natural History and Albert Kollar is Collections Manager for the Section of Invertebrate Paleontology. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

The Bromacker Fossil Project Part VIII: Martensius bromackerensis, Honoring a colleague

Adult, holotype specimen of *Martensius bromackerensis*. Image digitally assembled by the author from five photographs taken by Diane Scott (Preparator at University of Toronto Mississauga [UTM]), 2010–2013. The specimen was collected in several large blocks.

The formal publication of some of the Bromacker discoveries took more time to complete than others, and our most recently pubished fossil, Martensius bromackerensis, holds the record in that regard. Four nearly complete specimens of Martensius were collected from the Bromacker quarry between 1995–2006. The first, discovered by Thomas Martens and his father Max, came from a jumbled pocket of fossils. Unfortunately, muddy groundwater had penetrated cracks in the subsurface of this portion of the quarry and coated and eroded bone present along these cracks. Despite this damage and the lack of a skull, we could identify the specimen as a caseid synapsid (synapsids, also known as mammal-like reptiles, are a group of amniotes whose later-occurring members gave rise to mammals).

Drawing of 1995 *Martensius bromackerensis* specimen. Because the specimen was collected in numerous pieces of rock, with parts of some bones exposed on apposing rocks, Scientific Illustrator Kevin Dupuis (UTM) had to first draw the bones exposed on each piece and then assemble all of the drawings digitally. Dotted lines indicate bone impression in the rock. Arrows point to healing scars from two fractures in the last right rib. Additional healing scars can be seen in preceding ribs. This animal apparently survived a serious injury. Modified from Berman et al., 2020.

The next specimen was discovered in 1999 by Georg Sommers (Preparator, Museum der Natur, Gotha), who prepared the fossil. It consists of a vertebral column, ribs, some limb bones, and a few scattered skull elements. Unfortunately, a more complete skull was needed to allow for comparison to other caseids, some of which are based only on skull material. It wasn’t until the discovery of two more specimens in 2004 and 2006 by Stuart Sumida and Dave Berman, respectively, that the long sought-after skull was found. Preparation of these specimens took a long time due to their size and the considerable amount of rock covering the bones in some of the blocks. My promotion to Collection Manager in 2005 left me with considerably less time to prepare fossils. Other preparators were asked to help with the preparation at both Carnegie Museum of Natural History (CMNH, Dan Pickering and Tyler Schlotterbeck) and in Dr. Robert Reisz’s lab at the University of Toronto at Mississauga (Diane Scott and Nicola Wong Ken). Robert was originally slated to lead the study, but other commitments prevented him from working on it, so Dave took over.

Besides preparation, the scientific study and publication of the specimens required illustrations and photographs, most of which were done by Diane, Nicola, and Kevin. Andrew McAfee (Scientific Illustrator, CMNH) made skeletal and flesh reconstructions of the animal, as well as an illustration of two Martensius in their ancient habitat (see The Bromacker Fossil Project Part III for a link to this illustration). All of this effort was worth it, however, because besides adding to the diversity of the Bromacker vertebrate fauna, Martensius has an unusual life history.

Juvenile specimen of *Martensius bromackerensis*. Image digitally assembled by the author from two photographs (skull and body) taken by Diane Scott in 2013. The skull, shown in ventral aspect, is incomplete and eroded on its dorsal surface.

Caseid synapsids are a diverse, long-lived group known from the Late Pennsylvanian–Middle Permian epochs (~300–259 million years ago) of Europe, Russia, and the USA, and, with one exception, all are adapted to eating plants (herbivorous). The most advanced caseids (such as the enormous Cotylorhynchus romeri) have ridiculously small skulls when compared to those of carnivores, spatulate (spoon-shaped) teeth tipped with small tubercles (cuspules) for cropping vegetation, and huge, barrel-shaped ribcages to support a large gut for fermenting cellulose-rich plants. The exception is the earliest known (Late Pennsylvanian epoch, ~300 million years ago) caseid, Eocasea martini, represented by a single, incomplete juvenile specimen from Kansas. The teeth of Eocasea are small and conical, which indicate that it most likely ate insects. Because it’s skull and ribcage are of normal size, in contrast to juveniles of Martenius, Eocasea probably ate insects throughout its life.

Reconstruction of the skull of *Martensius bromackerensis* (left) from the Early Permian (~290 million years ago) Bromacker quarry, Germany, and the more advanced caseid Ennatosaurus tecton (skull, middle and skull fragment with cuspule-tipped teeth, right), from the Middle Permian (~263 million years ago) of Russia. Skull reconstruction of *Martensius* made by Diane Scott and modified from Berman et al., 2020. Ennatosaurus skull reconstruction and jaw fragment drawing modified from Maddin et al., 2008.

Martensius has a modestly expanded ribcage and a small skull, suggesting that it was herbivorous. Furthermore, the feet of Martensius, like those of other caseids in which the feet are known, are large, with massive, elongated, strongly recurved claws. Martensius also has a well-supported hip region that may have enabled it to rise on its hind legs to reach and tear down overhead branches to feed upon.

The upper and lower teeth of the adult Martensius differ from those of more advanced caseids in being triangular and lacking cuspules. The upper jaw teeth of the juvenile resemble those of the adult, but the lower jaw teeth are more numerous—31 in the juvenile compared to 25 in the adult—and surprisingly, they resemble those of Eocasea. Dave concluded that juveniles of Martensius had teeth adapted for eating insects, which were replaced by an adult dentition that would’ve been good for cropping plants and piercing insects. Remarkably, the juvenile Martensius apparently died while in the process of replacing its juvenile dentition with that of adults.

So why have different juvenile and adult dentitions? Modern animals that eat fibrous plant matter have micro-organisms called fermentative endosymbionts in their large guts, which break down difficult-to-digest plant matter via fermentation. It is assumed that early fossil plant-eaters with broad ribcages also had large guts housing fermentative endosymbionts. Prior to the discovery of Martensius, other scientists hypothesized that early herbivores acquired endosymbionts by eating herbivorous insects that already had these microbes in their guts. In Martensius, the introduction of endosymbionts apparently occurred during the juvenile, insectivorous stage of life, which set the stage for adults to add plants to their diet.

Flesh (top) and skeletal (bottom) reconstructions of *Martensius bromackerensis*. Illustrations by Andrew McAfee and modified from Berman et al., 2020.

The generic name Martensius honors Thomas Martens for his discovery of vertebrate fossils at the Bromacker quarry and his perseverance in maintaining a highly successful, long-term field operation resulting in the discovery and publication of the exceptionally preserved Bromacker fossils. Bromackerensis refers to the Bromacker quarry, the only locality from which this species is known.

Stay tuned for my next post, which will feature some terrestrial dissorophoid amphibians.

For those of you who would like to learn more about Martensius, here’s a link to the 2020 Annals of Carnegie Museum publication in which it was described.

Amy Henrici is Collection Manager in the Section of Vertebrate Paleontology at Carnegie Museum of Natural History. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

Keep Reading

The Bromacker Fossil Project Part IX: The Dissorophoid Amphibians Tambachia, Rotaryus, and Georgenthalia, Capable Travelers

June 29, 2020 by wpengine

Mesozoic Monthly: Protostega

June 20^th was the first day of summer! The weather here in Pittsburgh is already beautiful. It’s enough to make one dream of a socially distant beach! Summer, of course, is sea turtle nesting season: during the next several weeks, female sea turtles all across our planet’s Northern Hemisphere will return to the beach where they hatched, drag themselves onto land, and lay their eggs in the sand. It would have been an incredible sight to see Protostega gigas, one of the largest sea turtles of all time, hauling itself onto the beach to lay its eggs! For June’s Mesozoic Monthly, we’re going to “dive in” to the paleontology of this giant reptile.

Carnegie Museum of Natural History’s spectacular skeleton of Protostega gigas is a composite made from the fossilized bones of two different individuals. Come see it on display in our Dinosaurs in Their Time exhibition when the museum reopens at the end of this month. But don’t forget to purchase your timed ticket in advance!

All turtles, including sea turtles like Protostega and tortoises like the Galápagos giant tortoise, belong to the group Testudines. This group originated during the Triassic Period, the first of the three time periods of the Mesozoic Era (aka the Age of Dinosaurs). Turtles split from other reptiles to form their own group before crocodiles and dinosaurs evolved! This means that turtles are not descended from dinosaurs, no matter how primordial some tortoises may look. Turtles differ from other reptiles in many ways, the most noticeable being their iconic shells.

A turtle shell is formed of two main parts: the carapace, or top shell, and the plastron, or bottom shell. The shell is made of bone fused directly to the spine and ribcage, so a turtle cannot crawl out of its shell without leaving its skeleton behind! Another major difference between turtles and other modern reptiles involves skull anatomy. Turtles have anapsid skulls: the bony case that protects their brain lacks any external openings behind their eyes (known as temporal openings). All other extant reptiles plus birds are diapsids, meaning their skulls have two holes behind their eyes. Mammals differ from both conditions because we have only one temporal opening, making us synapsids. Traditionally, the anapsid condition of turtle skulls has been taken to indicate that they are the most primitive of living reptiles. More recently, however, many paleontologists and biologists have uncovered evidence that turtles are in fact diapsids whose evolutionary course led, for some reason, to a secondary closure of their temporal openings. According to these scientists, the closest relatives of turtles among today’s diapsids are either lepidosaurs (lizards, snakes, and kin) or archosaurs (crocodilians and birds).

A bird’s (or pterosaur’s!) eye view of Protostega gigas (left) swimming past two long-necked elasmosaurid plesiosaurs in shallow waters of North America’s Western Interior Seaway roughly 85 million years ago. (This scene is set in what’s now Kansas!) Art by Julio Lacerda; see more of his beautiful work here.

Reptiles, mammals, and birds all belong to a group called Amniota, and the key defining feature of amniotes is a protective layer around their eggs that allows this vulnerable life stage to survive on land. Having eggs that did not have to be laid in water meant that animals could move to less-wet habitats, a significant step in evolution! Unfortunately for sea turtles, which spend most of their lives at sea, this means they must return to land to lay their eggs. An amniotic egg would “drown” in water because the embryo still needs access to air. As a sea turtle, Protostega would have faced these same reproductive challenges, plus one more: it was huge!The largest modern turtle, the leatherback sea turtle, can grow over seven feet (2.1 meters) long; Protostega dwarfs it at 9.8 feet (3 meters)! If you’ve ever seen video of a sea turtle crawling onto the beach to nest, you know that it’s an awkward process. Imagine seeing a turtle that weighs at least a ton try to do the same! Although surely clumsy on land, Protostega was a graceful swimmer, using its four rigid flippers like wings to “fly” through the water.

Protostega lived in the Western Interior Seaway, an inland sea that stretched across much of North America during the Cretaceous Period (the third and final period of the Mesozoic Era). The seaway was warm, shallow, and teeming with all kinds of aquatic life: the perfect habitat for an omnivorous sea turtle. Because sea turtles are ectothermic (sometimes erroneously called “cold-blooded”), they cannot regulate their own body temperature. Instead, Protostega relied on warm water temperatures and sunlight hitting its back to keep warm. Although we don’t have a fossil record of the coloration of Protostega, we know that today’s large sea turtles are counter-shaded, with heat-absorbing, dark-colored backs and pale undersides. In an ocean environment where both predator and prey shift positions in the water column, this combination aids concealment. From below, a light-colored underside blends with light-saturated water. From above, a dark back blends with dark water. Camouflage in the water was an important feature when living alongside so many sizable predators. Protostega fossils have been found with bite marks from the large shark Cretoxyrhina mantelli, and it almost certainly was also on the menu for the mighty mosasaurs as well. Fortunately for us, we humans can enjoy the ocean knowing that few creatures are interested in eating us!

Lindsay Kastroll is a volunteer and paleontology student working in the Section of Vertebrate Paleontology at Carnegie Museum of Natural History. Museum staff, volunteers, and interns are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

The Bromacker Project Part VI: Seymouria sanjuanensis, the Tambach Lovers

New to this series? Read The Bromacker Fossil Project Part I, Part II, Part III, Part IV, and Part V.

Seymouria sanjuanensis fossils — Two exquisitely preserved, nearly complete adult skeletons of *Seymouria sanjuanensis* that were discovered in the Bromacker quarry in 1997. Photo by Dave Berman.

At lunchtime on the last day of the 1997 field season, Thomas Martens discovered the two exquiste specimens shown above, the only fossils found that year. Thomas had uncovered a piece of the hip region with some attached vertebrae that resembled, once again, those of the ancient amphibian Seymouria. Because our work time was limited, we estimated the length of the specimen and rushed to extract it from the quarry. When we flipped the block over, a few pieces of rock fell out, revealing a series of vertebrae of a second individual in the block. We were thrilled to learn that Thomas had discovered two specimens of Seymouria. We put the rock pieces back in place and quickly finished plastering the block. There was just enough time for Dave, Stuart Sumida, and I to return to our hotel, clean up, quickly pack, and meet Thomas, his family, and his fossil preparator Georg Sommer for a celebratory dinner. What a great way to end the field season.

Working in tight quarters to quickly extract the *Seymouria* specimens discovered at lunchtime on the last day of the field season. Clockwise from right: Georg Sommer, Dave Berman, and the author. Photo by Stuart Sumida, 1997.

Seymouria had already been known from the Bromacker quarry. Thomas had discovered and identified two skulls in 1985, fossils he brought with him when he came to Carnegie Museum of Natural History (CMNH) in 1993 to study for six months with Dave Berman under a CMNH-financed fellowship. Both skulls were of juvenile individuals. Of the two known species of Seymouria, Dave and Thomas were excited to discover that the Bromacker skulls were nearly identical to those of Seymouria sanjuanensis. The 1997 lunchtime discovery of the two complete adult specimens confirmed the identification of the Bromacker Seymouria as S. sanjuanensis.

The first discovered species of Seymouria was Seymouria baylorensis, from near Seymour, Baylor County, Texas, from which its name was derived. Seymouria sanjuanensis was first found in San Juan County, Utah, by Dave Berman and the field team he was leading as a graduate student at the University of California, Los Angeles. Dave’s advisor, Dr. Peter Vaughn, named it Seymouria sanjuanensis in reference to the county of discovery. Another discovery of five specimens of this species preserved together was made by Dave in New Mexico in 1982.

Comparison of the skulls of *Seymouria baylorensis* (top) and *S. sanjuanensis* (bottom). The individual bones of the skull are color coded. Skulls scaled to same size. Image from Wikimedia Commons.

Seymouria baylorensis is geologically younger than S. sanjuanensis and has a more robust skull, larger and fewer teeth of variable size, and a subrectangular postorbital bone compared to the chevron-shaped postorbital of S. sanjuanensis.

Seymouria is considered a terrestrial amphibian that only returned to water to breed. Its strongly built skeleton provided the support needed to move on land. With its numerous, slender, pointed teeth, S. sanjuanensis most likely ate insects and small land-living vertebrates. We know that the Bromacker Seymouria didn’t consume fish, because not a single fish fossil, scrap of fish fossil, or fish coprolite (fossil poop) has ever been found at the Bromacker quarry. Study of the rock deposits preserving the fossils at the Bromacker indicate a lack of permanent water, which would explain the absence of fish.

Growth series of skulls of *Seymouria sanjuanensis* from the Bromacker Quarry showing (left to right) early juvenile, late juvenile, and adult growth stages. Photos by the author, 2006.

Conditions for breeding must have been favorable in the Tambach Basin, the ancient basin where sediments preserving the Bromacker fossils accumulated, because several juvenile specimens of Seymouria are known. The smallest is a skull measuring about ¾ of an inch long. In a study led by our colleague Josef Klembara (Comenius University, Slovak Republic), we determined that the smallest individual was post-metamorphic—in other words, no longer a tadpole—based on the presence of certain ossified bones in the skull. In tadpoles, these skull elements are cartilaginous; that is, they haven’t yet turned to bone.

The discovery in Germany of the same species of Seymouria previously known only from New Mexico and Utah has important implications in terms of paleobiogeography (the study of the distribution of species in space and time). At the time S. sanjuanensis was alive, the continents were merged to form the supercontinent Pangaea. The presence of S. sanjuanensis across Pangaea, north of a roughly east-west trending mountain range, indicates that climatic or physical barriers (e.g., deserts, inland seas, mountain ranges) didn’t prevent its dispersal.

Map showing the arrangements of the continents in the Early Permian. The locality where *Seymouria* occurs in present-day New Mexico, Texas, and Utah and the Bromacker locality in present-day Germany are indicated. Map modified from Scotese, 1987.

The two Seymouria specimens preserved together were a big hit in the local region in Germany. Museum der Natur (MNG) exhibit preparator Peter Mildner nicknamed them the “Tambacher Liebespaar” (“Tambach Lovers”) after a painting entitled “Gothaer Liebespaar” (“Gotha Lovers”) on exhibit in the Herzogliches Museum of the Stiftung Schloss Friedenstein (also the parent organization of MNG). This name caught on and is fondly used by our German friends and colleagues. Peter even made a fleshed-out model of the two Seymouria specimens in their death pose. The proprietor of the hotel in which we stayed hung a copy of the model of the Tambach Lovers and a framed collage of newspaper articles featuring the Bromacker on a wall in one of the hotel rooms, which she named the “Präparation Suite” (i.e. “Preparation Suite” in reference to the preparation of fossils). I often stayed in this room.

The painting entitled “Gothaer Liebespaar” (“Gotha Lovers”), which is on display at Herzogliches Museum of the Stiftung Schloss Friedenstein, Gotha, Germany. Image from Wikimedia Commons and provided by Thomas Martens.

Tambach Lovers postcard — Postcard showing the Tambach Lovers. The postcard was made for and sold by the Museum der Natur, Gotha. Photo of the postcard by the author, 2020.

Stuart Sumida (left) and Heike Scheffel, proprietor of the Hotel Wanderslaben where we stayed (right), with the model of the Tambach Lovers in the “Präparation Suite.” The framed collage to the right of the model holds newspaper articles featuring the Bromacker project. Photo by the author, 2003.

A cast of the Tambach Lovers specimen and a model of Seymouria sanjuanensis are exhibited in the Fossil Frontiers display case in CMNH’s Dinosaurs in Their Time exhibition. Be sure to look for them once the museum re-opens. And stay tuned for my next post, which will feature the unusual bipedal reptile Eudibamus cursoris.

For those of you who would like to learn more about Seymouria sanjuanensis, here is a link to the publication describing the 1997 specimens: https://www.tandfonline.com/doi/abs/10.1671/0272-4634(2000)020%5B0253%3AROSSSF%5D2.0.CO%3B2.

Keep Reading

The Bromacker Fossil Project Part VII: Eudibamus cursoris, the Original Two-legged Runner

May 14, 2020 by wpengine

The Bromacker Fossil Project Part II: The Hunt for Fossils

New to this series? Read The Bromacker Fossil Project Part 1 here.

Finding fossils at the Bromacker quarry was tedious and physically demanding, but it was extremely rewarding when a fossil is discovered. Our annual summer field season generally lasted three and a half weeks. Because the weather usually wasn’t conducive to camping or cooking outdoors, we stayed at the same hotel and dined at the hotel or local restaurants.

The original 1993 fossil quarry was opened using heavy equipment and operators from the nearby commercial quarry, and in the early years we relied on these people to expand the fossil quarry’s boundaries as needed. When the commercial quarry was temporarily shut down due to the lack of contracts for building stone, our collaborator Dr. Thomas Martens fortunately was able to obtain funding to annually rent a Bobcat, which he became skilled at operating. Thereafter, Thomas would use the Bobcat to expand the quarry and remove soil and weathered rock layers, so that we could begin our yearly excavation on unweathered rock.

The Bromacker quarry on the first day of fieldwork in the 2006 field season. Shovels were used to clear loose rock from the surface of the quarry. Pictured (counterclockwise from left) graduate student Andrej Čerňanský and Dr. Jozef Klembara (Comenius University, Bratislava, Slovak Republic) and Dr. Dave Berman (Carnegie Museum of Natural History [CMNH]). Photo by the author, 2006.

We would each stake out an area of the quarry to work in and then proceed to work through the rock layers by using a hammer and chisel or pry bar to free a piece of rock. Its surfaces and edges would be checked for fossil bone, and if there was none, the rock piece would be broken into smaller pieces, which were also checked for bone. As is the case at many other fossil sites, the rock tended to split along the plane a fossil was preserved in, because the fossil would create a zone of weakness.

The quarry after a couple days of excavation. Pictured (clockwise from front) are Dave Berman, Jozef Klembara, and Andrej Čerňanský. Photo by the author, 2006.

Once a fossil specimen was discovered—and there were a few frustrating years when this didn’t happen—the hard work of extracting it from the quarry began. Here, I’ll use a fossil discovered during the 2006 field season as an example of how this was done.

A discovery! Fossil bone and bone impression are exposed to the left of the lens cap. Photo by the author, 2006.

First, we would isolate the fossil specimen from the surrounding rock, exposing as little of the fossil as possible while determining its extent, because it would have been easy to lose pieces of bone in the dirt and mud. Then we would encase the specimen in a plaster and burlap jacket to protect it during extraction, shipping, and preparation.

To make the jacket, we’d coat cut strips of burlap in wet plaster and then spread them across the surfaces of the rock containing the specimen, or block. A layer of plastic (plastic bags worked well) was applied to the top surface of the block to keep plaster from sticking to any exposed bone.

The block is partially isolated from surrounding rock. In this case, we decided to encase the top and some sides of the block in plaster and burlap bandages to hold the rock pieces together before we finished isolating the block from surrounding rock. Photo by the author, 2006.

After a couple layers of plaster bandages were applied to the top and sides of the block, the block was undercut, with plaster bandages added periodically to hold the undercut rock in place.

Pictured (left to right) are Dr. Stuart Sumida (California State University, San Bernardino, CA), Dave Berman, and Mr. Jerome Gores (Museum der Natur, Gotha [MNG]). Jerome is holding a plaster and burlap bandage while Dave and Stuart are pressing plaster bandages against the bottom of the block. They must hold the bandages in place until the plaster sets. Photo by the author, 2006.

Using hammers and chisels to undercut the block. Photo by the author, 2006.

When deemed safe, we would crack the block free from the quarry floor using hammers and chisels, and flip it over, unless it broke free on its own. Excess rock would be removed from the bottom of the block to make it lighter in weight. Then we would apply burlap and plaster bandages to the bottom of the block. The block would be removed from the quarry and stored at the MNG until it was shipped to Pittsburgh.

The block has now been safely flipped over and excess rock is being removed. Photo by the author, 2006.

We encountered several problems during our quarry operations over the years. As we worked our way through the rock column in the quarry, processed rock piled up on the quarry floor. In the early years, we tossed or shoveled the processed rock into wheelbarrows and pushed the heavy, unwieldy wheelbarrows out of the quarry to a dump pile. Fortunately, the Bobcat eventually replaced the wheelbarrows for moving processed rock. As we ran out of space outside the quarry to dump processed rock, the rock was used to backfill older portions of the quarry.

Former CMNH volunteer Linda Rickets (front, right) and the author (left, rear) line up to push loaded wheelbarrows out of the quarry to the dump pile. Photo by Dave Berman, 1996.

At the dump pile. Over time rain and the freeze/thaw cycle would break down the rock and vegetation would grow on it. Photo by Dave Berman, 1996.

Another problem was that fossils found at the bottom of the quarry were often extremely difficult to undercut because the rock so was hard. Sometimes a well-hit chisel would just bounce off the rock instead of cracking or penetrating it. One year we had to resort to a rock saw to undercut a block.

Dave Berman uses a rock saw to undercut a block. Photo by the author, 2004.

Rain was always a problem. We would shelter in our cars during intervals of rain, or work at the museum if the rain was heavy and persistent. Occasionally heavy rain would flood the quarry, forcing us to work in the ‘dry’ areas of the quarry while a pump drained the water. Of course, we had contests to see who could skip a rock the farthest or make the biggest splash.

A flooded quarry greeted us in the morning after heavy overnight rain. Pictured are Thomas Martens (front) and Stuart Sumida (rear). Photo by the author, 2010.

Next week’s post will describe the process of fossil preparation, that is, removing rock to reveal a specimen in the lab. The fossil collected in the 2006 field season will be used as an example.

Here are some videos taken by taken by Thomas Martens’ wife, Steffi, during the 1993 and 2006 field seasons. These show the process of searching for fossils (1993 video) and collecting the fossil highlighted in this post (2006 videos).

Bromacker Quarry 1993

https://youtu.be/DAEG0l1NotE

Bromacker Quarry 2006

https://youtu.be/UNL1s5ycJSM

https://youtu.be/lqYxheOZLQY

https://youtu.be/HrmSBrhde_E

Amy Henrici is Collection Manager in the Section of Vertebrate Paleontology at Carnegie Museum of Natural History. Museum staff, volunteers, and interns are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

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October 15, 2019 by wpengine

Carnegie Geologists Win National Award

In the fall of 2018, Albert D. Kollar and John A. Harper (volunteer and research associate) of the Section of Invertebrate Paleontology in collaboration with the Pittsburgh Geological Society conducted a geology field trip titled: Geology of the Early Iron Industry in Fayette County, Pennsylvania. Back then, we had no idea this field guide would be recognized by the Geoscience Information Society with their GSIS Award 2019 for Best Guidebook (professional) at the Annual Meeting of the Geological Society of America (GSA). On September 23, 2019, Albert attended the Awards Luncheon in Phoenix, Arizona, to receive the GSIS Award.

Albert D. Kollar and Michael Noga representing Geoscience Information Society.

As stated by the GSIS committee chair, “The Geology of the Early Iron Industry in Fayette County, Pennsylvania is well-written and well-illustrated, with both professional and popular sections. I can see local geology teachers taking students on these trips to show a chapter in the development of an important early ore industry in the United States. With the aid of detailed road logs guidebook users can see and learn about the geology, industrial development, history, and fossils in Fayette County. Field Trip leaders can use the guidebook to expand on several topics, depending on the interests of their trip attendees. An additional benefit of the guidebook is its free availability online, so any traveler with an interest in the area can explore on their own. The Pittsburgh Geological Society has performed a great model for other local societies that are interested in spreading the benefits of their field trips to wider audiences.”

In receiving the award, Kollar opined that the guidebook has been recognized for the diverse geology of the region and the many historical sites that can be seen and visited respectively throughout southwestern Pennsylvania. These include, the geology of Chestnut Ridge, a Mississippian-age limestone quarry with abundant fossils and Laurel Caverns, the history of oil and gas exploration, the historic Wharton Charcoal Blast Furnace, the geology of natural gas storage, the country’s First Puddling Iron Furnace, and the birth place of both coke magnate Henry Clay Frick and Old Overholt Straight Rye Whiskey, West Overton, Westmoreland County, Pennsylvania.

Another feature of the guidebook is its dedication to Dr. Norman L. Samways, retired metallurgist, geology enthusiast, and good friend who spent many years as a volunteer with the Invertebrate Paleontology Section of the Carnegie Museum of Natural History. Sam, as we called him, passed away in February 2018. His contribution came about when he was instrumental in the research and writing of the Geology and History of Ironmaking in Western Pennsylvania, with his co-authors John A. Harper, Albert D. Kollar, and David J. Vater, published as PAlS Publication 16, 2014. Moreover, Sam was solely responsible for a new historical marker, AMERICA’S FIRST PUDDLING FURANCE along PA 51, dedicated on September 10, 2017 by the Pennsylvania Historical & Museum Commission and the Fayette County Historical Society. David Vater contributed to the guidebook’s content by drawing a schematic diagram of a typical puddling iron furnace, which is greatly appreciated. Key fossils and iron ores of the section’s collection are referenced as well. The cataloged fossils cited in peer review journals authored by section staff and research associates includes those on the trilobites by Brezinski (1984, 2008, and 2009), Bensen (1934) and Carter, Kollar and Brezinski (2008) for brachiopods, and Rollins and Brezinski (1988) for crinoid-platyceratid (snail) co-evolution.

In recent years, the section has run highly successful regional field trips about various geology and paleontology topics based on the museum collections, collaborations with the Pittsburgh Geology Society, the Geological Society of America, Osher Institute of the University of Pittsburgh, Nine-Mile Run Watershed, Allegheny County Parks, Pittsburgh Parks Conservancy, Montour Trail, Carnegie Discovers, and the section’s own PAlS geology and fossil program. A future field trip is being planned to assess the dimension stones that built the Carnegie Museum and noted architectural building stones of Oakland.

Albert D. Kollar is the Collection Manager in the Section of Invertebrate Paleontology at Carnegie Museum of Natural History. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

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