This issue our featured professional is Amy C. Henrici, Collection Manager of the Section on Vertebrate Paleontology at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania. Amy was kind enough to provide thoughtful answers to questions asked by Eleanor Gardner, FOSSIL Project Coordinator.
Where has your field work taken you? I noticed that you have been describing early amphibians and reptiles from a Lower Permian quarry site in Germany. Can you tell us more about your research there, and what the field work is like?
Over the years I have collected a variety of fossils from the United States and Germany. Fossils collected include fish, amphibians and reptiles from the Early Permian of the southwestern United States; the dinosaur Coelophysis bauri and other fossils from the Triassic of New Mexico; frogs and mammals from the Tertiary of Wyoming, Montana, and Nevada; and mammals from the Pleistocene of West Virginia. One of the more exciting field and research programs that I have been involved in is the Bromacker Quarry locality in central Germany. This project began in 1993, shortly after the reunification of Germany when the Carnegie Museum of Natural History (CMNH) hosted for six months Dr. Thomas Martens from the Museum der Natur, Gotha, Thuringia, Germany. Martens in 1974 had discovered some interesting Early Permian vertebrate fossils in the Bromacker Quarry that resembled taxa formerly known only in North America. At this time Thuringia was part of communist East Germany, so Martens was not able to travel outside of the Soviet bloc countries. Because Martens was trained as an invertebrate paleontologist he knew he had to contact an expert on Early Permian tetrapods from North America to help him identification and publication of the Bromacker fossils. After the reunification of Germany, Martens began a collaboration with Dr. Dave Berman, a curator at CMNH who specializes in Early Permian vertebrates. I became involved in this project, because I was Berman’s fossil preparator, but he later invited me to become a co-author of some of the research papers.
Berman and I, along with other colleagues, would join Martens in the field for three and a half weeks each summer to excavate at the Bromacker Quarry locality. The quarry is located in a large field that also serves as a summer pasture for cattle. Typically, a bobcat was rented to remove overburden, and then we used hand tools, such as hammers and chisels and pry bars, to work through the fossil-bearing rock layers. Once a fossil was discovered, we removed it using the standard technique of encasing it in a plaster and burlap jacket. The work was laborious and at times tedious, especially if fossils were not being found. The weather was variable with some summers being cold and rainy (a Scandinavian summer) or very hot and humid (an Italian summer), or sometimes a mix of both. The quarry would often be flooded when we arrived in the morning after a night of heavy rain, so we would have to pump the water out with a small motorized pump run on a gasoline generator. We stayed at a local hotel, where we were treated like family. The international field crew would gather for dinner each night either at the hotel or one of the restaurants in the numerous villages dotting this rural area.
Twelve different types of amphibians and reptiles are known from the Bromacker Quarry area. All but one was collected from the Bromacker Quarry, with the other discovered during the construction of a market in a nearby town. The fossils were deposited in an upland, internally drained basin, the Tambach Basin. Sheet flooding events were most likely the cause of death and rapid burial, leading to fossilization. The fossil animals from the Bromacker represent a unique upland terrestrial ecosystem with a high number of herbivores supporting a small number of top carnivores. A more typical Early Permian assemblage tends to have a high number of carnivores and only a few herbivores. To date, no aquatic vertebrates have been discovered at the Bromacker. Some of the fossil genera were previously known only from the western United States, whereas others are unique to the Bromacker. One of the more interesting discoveries is the bolosaurid parareptile, Eudibamus cursoris, which is the earliest known bipedal runner. Not only was Eudibamus bipedal, but it ran in an upright posture, rather than a sprawling gait used by today’s bipedal lizards, such as Basiliscus basiliscus, the common basilisk.
What is a typical work day like for you? What are some of your favorite parts of your job? Your least favorite?
My typical day begins with checking my email, and this often sets the course of the day. Somedays I might have a couple of emails, whereas on others I may have over 20. I often receive via email requests for loan of specimens or for information about the collection. I typically try to answer these as they come in. If I have no immediate requests to fill or collection visitors, then I’ll work on a grant project funded by the Institute of Museum and Library Services. This grant involves consolidating the section’s holotype fossils into new cabinets purchased by the grant. Each fossil is cleaned, repaired, photographed, and a support mount is made of conservation-grade materials. I am currently photographing holotype specimens and making drawer and cabinet labels. When I am not working on this project, then I am putting away specimens that had been collected by one of our Scientific Preparators who recently passed away. Occasionally I participate on an exhibit committee. My role on exhibit committees is to provide lists of potential specimens for use in the exhibit, clean and repair the selected specimens, and assist with specimen installation. I sometimes am called on to edit and/or write label copy.
My favorite part of the job as a Collection Manager is to work with the specimens, whether it is to clean and repair them or to make specimen mounts. One of the things that aggravates me the most are improperly packed specimen loan returns, in which the specimens arrive broken. I also have little patience for computer malfunctions.
Do you have a favorite fossil discovery (can be your own, or a famous historical discovery)?
My favorite fossil discovery is the diadectomorph Orobates pabsti. I discovered what became the holotype specimen and is the most complete specimen known of this taxon. In the summer of 1998, I was with colleagues at the Early Permian Bromacker Quarry locality in central Germany excavating for fossils. I was working near the back wall of the quarry and near the bottom of the fossil producing unit when I picked up a piece of rock, turned it over, and saw a nearly complete foot preserved in it. I knew from past experience that if an articulated foot was found, the whole animal should be preserved in the rock. The rest of the crew heard the exclamation I uttered when I discovered the foot, and when they saw that I was staring intently at something, they quickly gathered around me. We examined the foot, but we could not tell if it was a front foot or a hind foot. One of the crew members removed another piece of rock from close to where I found the foot and saw what looked like a piece of shoulder girdle, so then we had a better idea as to how the animal was oriented. Fortunately, the long axis of the body paralleled the over six-foot-high back wall of the quarry, rather than penetrating it. A film crew from a local television station had visited us in the morning, so after hearing the good news they asked if they could come back for more filming. At their request, I reenacted the fossil discovery so they could film it. Because it was late in the day by the time the film crew finished, we covered up the fossil with rocks to hide it from anyone looking for fossils in the quarry after we left for the day. It took us the better part of the following day to excavate the fossil from the surrounding rock and encase it in a plaster and burlap jacket. After the field season ended, the fossil was shipped to the Carnegie Museum of Natural History where I spent over a year preparing it. The specimen is articulated and almost complete, lacking only the distal phalanx of one toe.
I was a co-author in the publication that named and described the new fossil as Orobates pabsti. The generic name is derived from the Greek, Oros, mountain, and bates, walker, referring to the paleoenvironment that the holotype specimen inhabited, a terrestrial upland basin. The trivial name pabsti is in honor of W. Pabst for his pioneering work on fossil trackways from the Bromacker Quarry locality. Orobates pabsti is a primitive member of the Diadectidae and was an herbivore. The fossil has since been returned to the Museum der Natur, where all of the fossils from the Bromacker Quarry locality reside.
To learn more:
Read about a 2010 discovery at the Bromacker Quarry in Germany at http://www.dw.com/en/
Berman, D.S., Henrici, A. C., Kissel, R. A., Sumida, S. S., & Martens, T. (2004). A new diactid (Diadectomorpha), Orobates pabsti, from the Early Permian of central Germany. Bulletin of Carnegie Museum of Natural History Number 35 :1-36. https://doi.org/10.2992/0145-9058(2004)35[1:ANDDOP]2.0.CO;2