Stephanie K. Drumheller-Horton, Paleontologist

All kinds of things can move, alter, or even destroy animals’ remains after they die, but before they fossilize and are discovered by paleontologists. The study of these processes is called taphonomy. I specialize in taphonomic processes affecting vertebrates (animals with backbones), especially archosaurs (crocodiles, dinosaurs, and everything in between).

American alligator (Alligator mississippiensis) bite mark collection on cow bones, at the St. Augustine Alligator Farm, Florida.

I work a lot with living animals to better understand extinct ones. In my bite mark research, this includes collecting crocodylian bite mark examples on pig and cow limbs. I have spent a lot of time at the St. Augustine Alligator Farm collecting data. By studying modern bone surface modifications, I am trying to find novel marks or patterns of marks, which can be used to positively identify similar structures on ancient bones. This lets me identify fossil traces left by particular behavior types or organism groups.

Bone surface modifications are traces on bone surfaces left by other members of or features in its paleoenvironment. This includes everything from sediment abrasion to carnivore bite marks. All of these different types of bone alterations can tell us something about the environment in which the affected animal lived and died. However, we can only access this information if we are able to correctly identify and interpret the marks. Once we can differentiate these marks, we can start asking questions about evolution and paleoecology. What kind of environment was here when these animals were alive? Who was eating what in this ecosystem? How did this animal become fossilized, and what might that tell us about the diversity of the original environment? Paleontologists are not the only people to consider how bones have been altered through time. Forensic osteology is a field of science dedicated to studying what happened to human bones based on features left on the bone material. Read more about forensic osteology here.

A) Line drawing cross section of a stereotypical mammalian long bone, with explanatory illustrations bite mark classifications. Photographic examples of bite mark types: B) Two pits made by an American crocodile (Crocodylus acutus); C) Puncture made by an American crocodile (Crocodylus acutus); D) Score made by a Chinese alligator (Alligator sinensis); E) Furrow made by a New Guinea crocodile (Crocodylus novaeguineae). Scale bars = 1 cm. From Drumheller & Brochu (2016).

The thrill of discovery is a big draw. When I find a new fossil out in the field, it’s pretty exciting to know that I am the first human being to ever see it. I feel the same thing about collecting data from lab experiments and field observations. Publishing a finished paper on a project can feel like you’ve been keeping a really cool secret, and now you finally get to share it with everybody.

Take as many opportunities to branch out and explore different fields as you can. You never know where they might lead you. My last semester of undergrad, I needed one more class to graduate. I already knew I wanted to be a paleontologist, I had actually already been accepted into graduate school. I ended up signing up for a forensic anthropology class, just because it sounded interesting, and my school had a world class program in the field. It was that class that introduced me to taphonomy and the study of bone surface modifications. One random elective class ended up shaping my entire career path.

Find out more about Stephanie’s research by checking out her Research Gate profile here or get more immediate information from her twitter here. Stephanie was part of a crowd funded experiment, found here, to excavate the Arlington Archosaur Site.

Fossil Collecting at Westmoreland State Park, Virginia

Adriane here-

An aerial view of Horse Head Cliffs at Westmoreland State Park overlook the Potomac River. The beautiful parallel layers of sediment contain fossils. Image courtesy of the VA Department of Conservation & Recreation.

Every now and then (well, as often as I can to be honest), I go fossil hunting with family, friends, and colleagues just for fun! There’s nothing like finding the remains of extinct animals and plants out in the field yourself. Although there are very few places where fossil collecting is prohibited, there are very few state parks and places in the US where it is encouraged. One of these places is Westmoreland State Park in Montross, Virginia.

This very well may have been the first place I found my very first fossil. I remember my dad had taken my siblings and I to the park one Saturday afternoon to play in the Potomac River and in the creeks and marshes nearby. But, once he told me we could find shark’s teeth on the river banks, my eyes were glued to the sand, systematically sweeping the ground in front of me. Lo and behold, I did find a shark’s tooth! And, it was a tooth that belonged to Carcharodon megalodon (or just Megalodon for short), one of the largest sharks to ever cruise the Earth’s oceans!

Stratigraphy of Westmoreland

Sifting for fossils on the banks of the Potomac River.

Westmoreland State Park is known among locals for its fossils, but any Virginia geologists will tell you the real gem of the park is its stratigraphy (well, OK, the fossils too). The oldest sediment that contain the fossils was laid down in a shallow extension of the Atlantic Ocean about 23-25 million years ago, during the lower Miocene. Younger sediments from the Pliocene (~5.3-2.5 million years ago) and Pleistocene (~2.5-0.01 million years ago) were laid atop the older Miocene deposits. Together, these different rock and sediment layers are called the Chesapeake Group. In the study of rock layers (=stratigraphy), a group includes different rock formations, each with their own name. For example, the Miocene formations in the Chesapeake Group (at least in parts of Virginia) are called the Calvert and Eastover formations.

After these formations were deposited, sea level dropped as glaciers on Greenland continued to grow. This allowed for rivers to flow further out into what was once a sea. Rivers are very powerful eroding mechanisms, as they have the capacity to move large boulders and wear down rocks (think of the Grand Canyon; it was made by the Colorado River cutting through the rock over time!) One of the rivers that now flows into the Atlantic Ocean is the Potomac River. This river is now eroding the Chesapeake Group formations, releasing all the fossils that were once contained in the rocks. Thus, some of these treasures wash ashore at Westmoreland State Park for visitors to find!

Fossils of Westmoreland

A small C. megalodon tooth found at Westmoreland State Park.

Over nearly a decade of visiting Westmoreland State Park, I have accumulated hundreds of shark teeth and found tons of other fossils. Some of these include whale teeth, vertebrae, rib bones and ear bones, dolphin teeth, vertebrae, rib bones and ear bones, fish vertebrae, shark vertebrae, coprolites (fossil poop), an alligator tooth, and mammal teeth. Most of these fossils are Miocene in age, but some are from the Pliocene and Pleistocene.

One of the most famous fossils to come out of the Chesapeake Group are those of the baleen whales. Several new species of whales have been found in Virginia in formations from the Miocene and Pliocene. One of these species, Eobalaeonoptera harrisoni, was found only five minutes down the road from my home in Virginia! E. harrisoni is a beloved icon of the area, in which it was found, so a complete cast of the whale now hangs in the Caroline County, VA visitor’s center.

The cast of Eobalaenoptera harrisoni that can be visited in the Caroline County, VA visitor’s center. Image from the Virginia Museum of Natural History.

National Science Foundation Proposals

Jen and Adriane here –

The National Science Foundation logo.

We are both writing up National Science Foundation (NSF) proposals. A proposal is a submitted document to any money granting agency. If the proposal is approved, the scientist(s) or educators who submitted the proposal is then awarded a grant in the form of money. Jen is submitting a grant for postdoctoral fellowship programs (postdocs are commonly 1-3 year appointments where you are further trained in research and writing after receiving your Ph.D.), and Adriane is writing up a full proposal with her advisor and colleagues to get funding for part of her dissertation (the document that is written for fulfillment of a Ph.D. program).

But before we go into the parts of an NSF proposal and how they are written, a bit more background about what these things are. In short, large grants (such as NSF or NASA) are the necessity of a researcher’s life. They are really large grants, usually on the order of ~$30,000 to sometimes over $2 million, that fund a scientists’ research, salary, and often the salary of their graduate students. There are different NSF programs; these can be thought of as different categories to which you can submit a proposal to. For example, Adriane is submitting a proposal to Marine Geology & Geophysics, a program that is great at funding all sorts of paleoceaonographic research.

If the scientist who wins the grant works at a university, the university takes part of the grant money for operating costs. This is fair, as the scientists use electricity, water, etc. in their labs, and the university also employs people to clean the buildings and grounds. Because the money from NSF grants comes, in part, from taxpayer monies, the entire review process a submitted proposal will go through is very rigorous. The granting agency wants to be sure taxpayer dollars are going towards research that will lead to the betterment of society in some way, or will fill a knowledge gap in the sciences that will open the doors for further research and development.

OK, now back to the parts of an NSF proposal:

Although we are submitting for very different purposes the format is relatively similar. There is a project summary that is a one page summary of your entire project. This is basically a one-page summary of your proposal, what you bring to the scientific community, and how you will provide something to the public through your work.

Figure from Jen’s recent postdoctoral fellowship proposal. She is interested in identifying how minor shape changes are shown in the skeletal elements of blastoids. Each plate circlet has a different color and as you can see on each of the blastoids the pattern quite different. These differences in plate shapes and sizes greatly affect how the organism would feed and breathe. The time periods that each animal lived are written below the specimens. This means that these differences continue through time, indicating an importance either evolutionarily or ecologically.

The project description is the full proposal that includes an introduction/background, your objectives and goals, the methods you will use, and the significance of the project. In addition, it includes lots of images and tables to justify why you want to do the science. Depending on the program you are submitting to there may be other things you need to incorporate into the project description. For example, Jen had to include an institution justification, professional development, and career training into her fellowship applications. To put this simply, why should you go where you are proposing to go – what does the school have that will help you succeed is the institution justification. Professional development means how will Jen grow as an academic while at the proposed institution – with details of projects or other mentoring opportunities. Career training goes hand in hand with professional development, this could be workshops or certificate programs that Jen can enroll in while at the proposed institution.

Adriane experiencing writer’s block on a Sunday morning. We can’t emphasize enough that these proposals do take a lot of time, and although they are lots of work, it is a huge honor to produce a successful NSF proposal!

Although the primary portion of the proposal is the project description, there are a series of additional files you must compile. The budget justification is a place to outline a detailed budget for the proposed project and explain what the funds are being used. Biographical sketches of the submitting members are required as well. This is a short summary of your education, training, publications, and other activities usually fit onto two pages. Collaborators and affiliations must be outlined as individuals that will not be asked to review your proposal. During the rigorous review process, NSF wants evaluation of proposals to be as unbiased and fair as possible, so they ask for a comprehensive list of all collaborators over the past several years. The data management plan outlines what will happen with all the data collected. This is particularly important because a key aspect of science is reproducibility (=the ability to reproduce another scientists’ results using their data).

So, there are a lot of pieces to writing an NSF proposal, and a lot of time goes into writing one! But probably the most important aspect to come out of research funded by the public is the ability for researchers and scientists to give back to the public in some way – whether that be through volunteering, lectures and teaching, or making fun websites to explain the science we are most passionate about so that everyone has access to our information 🙂

Fossil Summer Camp

Jen here –

Discussing teeth next to the T. rex replica in the geology gallery!
This past summer I was given the opportunity to redesign a summer camp that has been taught at the McClung Museum of Natural History and Culture for many years. I spent a long time going over the previous content from the summer camp and making it more engaging for the students. This meant coming up with new activities and crafts to keep the students occupied for three hours a day for one week.

The museum staff and I worked hard to promote the summer camp alongside the other camp for older students, Archaeokids! Archaeokids was a similar camp as the fossil camp but focused on archaeology rather than paleontology. Both archaeology and paleontology are fantastic sciences to get young students excited about learning. Both fields involve active learning by engaging the students with specimens from dig sites or fossil localities! I was asked to do a short interview to promote my camp to get more students enrolled, you can view it here.

Starting our sediment excavation outside on a beautiful day! The students also learned the importance of note taking.
Each day of the summer camp had a different theme that we could organize activities around. Here were the different themes in order: Fossils and fossil formation, rocks and the rock cycle, vertebrate anatomy, trace fossils, and artistic license and interpretation. The last activity of every day was exploring sediment to identify different animals that would have been found in the ancient environment. We had two teams one had sediment from the Ordovician and the other from the Mississippian. The first day we spent focusing on surface collection, just using our eyes to collect fossils from the pile of sediment. The following two days were spent sieving the sediment to see how things changed when we looked at a specific size of sediment and animals. The students really enjoyed being able to pick through the sediment to find the critters.

Exploring geologic time and taking about events that happened along the time scale.
The culmination of our sediment excavation was to draw out the environment that the sediment is recording. They were able to use a fossil guidebook that I made for them and the gallery exhibits of the reconstructed environments. They then were able to present their environments to their friends and discuss the differences! Both environments had some similar and some different animals. They got to pass around the different ones and talk about them. It was a very successful week and we all had a lot of fun!

Selina R. Cole, Paleobiologist

Collecting Devonian fossils in Spain
I am a paleobiologist interested in how evolutionary patterns are generated over geologic time through biological and environmental processes. Recently, my research has focused on why some organisms are at a greater risk of extinction than others. We know from the fossil record that species go extinct, but extinction patterns are not the same for all groups – some survive for millions of years, others are relatively short-lived. I focus on identifying what factors make a group more or less susceptible to extinction, including things like environmental tolerance, feeding ecology, body size, and habitat preference. I also incorporate phylogenetics (the study of evolutionary relationships among species) into my research to determine whether extinction risk is similar for species that are closely related.

I primarily work with fossils belonging to a group of sea creatures called crinoids, which are cousins to animals like starfish and sea urchins. Crinoids have an excellent fossil record that goes back almost half a billion years. There is also a lot of variation among crinoids in terms of their feeding styles, the habitats they lived in, and how their skeletons are constructed, so they are excellent model for exploring factors that contribute to extinction risk.

Much of my time is spent working in museum collections to document variation across hundreds of features in fossil crinoids, take measurements of specimens, and collect paleoenvironmental information from the rocks the fossils are embedded in. Other important data for my research comes from new species of fossil crinoids that I have collected and/or described myself, which helps improve our knowledge of species’ geographic and temporal distributions. Finally, I analyze my datasets to infer the evolutionary relationships between crinoids and to determine what factors contributed to differential extinction patterns.

A) Examples of fossil crinoids with different feeding structures and corresponding habitat requirements. B) Geological durations of crinoid genera in the fossil record, organized by their evolutionary relationships and color-coded by habitat.

Although grounded in the geological sciences, the field of paleontology is an important complement to biology and the study of living organisms because it includes a temporal dimension: the fossil record. The overwhelming majority of species that have ever lived are now extinct, so studies of extinct organisms are important for fully understanding the history of life. By identifying factors that caused past organisms to go extinct, we can better infer the extinction risk of species living today. This is important because species are currently going extinct at an unprecedented rate as a result of human-caused climate change and habitat destruction, which has the potential to significantly impact many aspects of society, such as fisheries, agriculture, and environmental sustainability.

One of my favorite parts about being a scientist is that I get to do a wide variety of jobs. On any given day, I may collect data from museum specimens, work at a computer to program a new analysis, write up research results, do science outreach with the public, conduct field work to collect new fossils, travel to a new part of the world to do research, or describe and illustrate a new species of crinoid. It never gets boring, and I get to stay creative by coming up with ideas that will take my research in new directions.
If you decide to study science, do so because it’s something you love. Pursuing a career as a researcher is hard work, but it’s worthwhile if you’re studying subjects you enjoy. It can be easy to get lose sight of what initially got you excited about research in the first place, so be sure to occasionally step back and remind yourself why you are passionate about what you do. Give yourself time to enjoy what you study and explore new research questions, which will help cultivate your scientific creativity and curiosity.

Lena is currently working in the Department of Paleobiology at the National Museum of Natural History. To learn more about her work visit her website here or her twitter here!

Rocky Mountain Field Trip

Megan here-

Image 1. Grand Teton National Park (in the red ellipse) is located in the northwest corner of Wyoming, just south of Yellowstone National Park.

An exciting perk of attending the University of Wyoming for graduate school is the annual Rocky Mountain Field Trip. This year, the geology faculty planned an adventurous trip to Grand Teton National Park and its surrounding areas (Image 1). Over five days, current and new graduate students explored the unique geology of the Tetons by learning about mountain formations, glaciation, and sedimentation in northwest Wyoming. By the end, we were able to develop an understanding of how this stunning area formed, and how it may change in the future.

Image 2. The view from AMK Ranch stretches across Jackson Lake to the Tetons. This photo looks southwest and shows the northern part of the north-south trending range.

For the first few days of the trip, we were lucky enough to stay at the AMK Ranch, which is home to the University of Wyoming-National Park Service Research Station. From here, we had a stunning view of Grand Teton National Park’s most impressive features: the high-standing peaks of the Teton mountain range (Image 2). These mountains are tremendously tall (the Grand Teton’s peak is 13,775 feet in elevation) due to a complex tectonic history of extension and uplift. Essentially, the mountains uplifted while the valley to the east dropped down. The pointed horns of the Tetons are a result of glacial sculpting during the Pleistocene Epoch.

One of the best parts of this trip was the variety of geology and geologists (Image 3). We learned about glacial geology, sedimentology, structural geology, hydrogeology, paleontology, and so much more. The professors and guests who joined us along the trip had a massive breadth of geologic knowledge. Not to mention, we were able to explore a national park with a geologic lens. That’s one of the most exciting things about being a geologist; you can look at landscapes with towering mountains and glacial lakes, or with meandering rivers and rolling hills, and you can envision the multitude of processes that formed that landscape.

Image 3. New and returning graduate students, UW professors, and even the UW provost mimic the pointed peaks of the mountains on a hazy day in Grand Teton National Park. Photo courtesy of Robert Kirkwood.

 

McClung Museum Temporary Exhibit on Echinoderms

Sarah and Jen here –

The outside of the McClung Museum with Monty, a replica of an Edmontosaurus.

Our local museum, the McClung Museum of Natural History and Culture, has a rotating small exhibit in their permanent geology gallery. They often contact the graduate students to showcase current research within our department (Earth and Planetary Sciences).

Our lab group (at the time) had three students, Sarah, myself (Jen), and Ryan. Each of us work on a different type of echinoderm (sea stars, sea urchins, sand dollars). Sarah works on these strange creatures called diploporitans, Ryan works on heart urchins, and I work on blastoids! We did an exhibit showcasing each of the different things that we do with our fossils. This ranges from finding new fossils on field excursions, visiting museums to study their collections, or running new experiments. Even though we study different organisms from different time periods, we all share a similar goal: to better understand these animals so that we can better assess relationships through time.

A photo of our echinoderm exhibit at the McClung Museum.

Andy Fraass, Paleoceanographer and Paleobiologist

I got into science because of Jurassic Park. I’ve always been fascinated by dinosaurs, but something about reading the novel, then watching that movie opening night just grabbed my brain and has never let go. When I got to college I realized that dinosaurs aren’t really the best way to ask the big questions that I’m interested in, like how evolution works, or how the possible shapes that an organism can have is shaped by evolution, or how past climate changes alter the course of evolution.

I study foraminifera because we (scientists) can find thousands – millions – in a single sample. We’re also not studying just a bone or two, we can find the entire shell. Having so many fossils to look at lets us be more sure of our findings. It’s so much cooler than dinosaurs. I know, I’ve yet to be able to convince anybody else of that.

I, as a micropaleontologist, also study past climates because it’s more important for society. Understanding evolution is important, but understanding the changes that our society, my daughter, and her kids (if she wants them) will experience is a more important use of my talents as a researcher and educator. I also use stable isotopes, the number of different fossil foraminifera with certain ecologies, and even just the sediments themselves to try and understand what controls past climate. One of the main findings of this field (called paleoceanography) is that our current changes in climate are unprecedented in well over 65 million years, with some research that concludes this is the most extreme climate change in about 400 million years (click here to read more about climate change and the geologic history of CO2 in Earth’s atmosphere).

The left part of the graph is a measure of diversity, or the number of different species or genera of planktic foraminifera. Geologic time is plotted along the top of the graph, measured in millions of years (Ma). The number of species (purple) and genera (gold) of planktic  foraminifera through time are plotted on the chart. The grey shapes in the background are the number of sites in the ocean that have rocks of that age. This graphic shows a clear large extinction at the end of the Cretaceous (~65 million years ago with a huge, sharp drop in diversity) and a more gradual change at the Eocene/Oligocene boundary (~34 million years ago).

My favorite part of science – bar none – are the people with whom I work. Figuring out questions and discovering things is wonderful, but the best part is doing it with people who are as enthused with science as I am. Science can be hard, and it can be very frustrating. I have the amazingly good fortune of having friends whose skills complement mine and who help get me through the frustration. There is nothing better than sitting around a table plotting out a three-year project with a couple of folks who are as excited about the scientific possibilities as I am.

Audrey Martin, Planetary Geoscientist

I am a planetary geoscientist, which means I study rocks from other planets and asteroids in the solar system! More specifically, I study a group of asteroids called Trojans. Most asteroids in the inner solar system are found in the Main Asteroid Belt, however Trojans are found further out. They orbit in two swarms and share an orbit with Jupiter (Figure 1). They have gravitationally stable orbits around the Sun, and probably haven’t moved for nearly 4.5 billion years (almost the age of the solar system!). Asteroids like this are called ‘primitive bodies’ and hold useful information about the environment in the early solar system before planets were made. I use Trojan asteroids to reconstruct major events that shaped our solar system.

Everything we see comes from photons in a very small sliver of the electromagnetic spectrum called the ‘visible.’ Trojan asteroids are some of the darkest objects in the night sky, so I ‘look’ at them in the thermal infrared (TIR). All objects in the universe radiate heat in the form of photons, and I look at the heat radiated by Trojans. This is basically how night vision goggles work! Using TIR data, I can examine the surface characteristics of Trojans (i.e., what minerals are present and texture) that are useful in determining their formation environment. By knowing how and where Trojans formed we learn more about what the solar system was like billions of years ago.

This is a figure of the relative positions of the inner planets (Mercury, Venus, Earth, and Mars) as well as Jupiter. The main belt orbits the sun between Mars and Jupiter. Notice the Trojan asteroid swarms, in orbit with Jupiter. This figure is definitely not to scale! From Planets for Kids, click through the image to get to their website!

Trojan asteroids are useful as ‘planetary fossils’ because they have been relatively undisturbed since the early days of the solar system. As such, they hold clues that are crucial for our understanding of the evolution of the solar system and planets. In 2021, NASA will launch Lucy a mission to the Trojan asteroids. The mission was aptly named after the fossilized hominid skeleton which helped form much of our knowledge on human evolution. In a similar manner, Lucy will collect data that are integral for understanding planetary formation and conditions in the early solar system.

My favorite part about being a scientist is learning more about how our solar system formed and gaining perspective on how precious Earth is. It is tremendously humbling to be a planetary scientist and research rocks that were formed in the solar nebula billions and billions of years ago, using data from spacecrafts that are currently over 200,000,000 km from Earth. And with the same spacecraft we can look back to Earth and see a small rocky planet, host to all the life we have ever known.

My advice to young scientists is to remain curious and keep asking questions. What you will find is with every question answered two more pop up, but keep asking. Sure, life as a scientist can be difficult, but that is not unique to a career in science. The unique aspect of being a scientist is that we get to expand the ‘bubble’ of human knowledge. As scientists, our endeavors are only limited by complacency. We will never know all that is there to know, but it is our job to keep searching and learning and discovering by asking questions.

Animations of Trojan Asteroids as they co-orbit the sun with Jupiter

Lightning Talks

Jen here –

Lightning or elevator talks are a great way to practice quickly sharing your research or work. Elevator talks are just as they sound, use the amount of time an elevator ride takes to share your research with another person. This is usually about 1-3 minutes, sometimes less! You can think of it sort of like a TV or radio commercial about what you do.

So, you want to make sure to share your science in a way that is not confusing to people in other scientific or academic fields. You want your research to be understandable to everyone, not just people that work on the same stuff as you. I find it helpful to pretend I’m talking to my mom who has a general understanding of what I work on but doesn’t particularly need to understand all of the minute details.

Below is my first official lightning talk. Since this is a video, I was able to include additional images and even an extra supporting additional video clip. I plan to produce a few a semester to practice communicating whatever my current research may be!

Here are some tools to begin crafting your own elevator talk!