What is your favorite aspect of being a scientist? How did you become interested in science?
My favorite part about being a scientist is learning something new every day. We get to ask and answer questions; some experiments are very large and involve many people and many years, and others are accomplished just by graphing our data in a new way. We also get to learn from our friends and colleagues, and from papers, talks, and lessons of the community. I really like my job because it is a great mix of field, lab, and computer work. I’m never bored, although some tasks are definitely tougher for me than others. Field work, conferences, and short courses have brought me all over the world, and this sort of travel is so exciting.
I’ve always looked for how to apply the things I’ve learned. I was good at math in school, but to me, applying those math skills to scientific questions was always more interesting. I thought I wanted to be a chemistry major at the beginning of college, but the Earth sciences incorporated the application of math, chemistry, physics, and biology to topics like volcanoes and earthquakes and climate change. I then studied geology, really digging into how the Earth moved over billions of years, but now I have further applied my scientific background to a topic that I find is absolutely crucial for us as a society to understand: climate change.
What do you do?
I study the natural variations of climate in Africa over many millions of years to understand how environmental change drove human evolution. I analyze rainfall, plants, and other climate parameters by studying fossil molecules that are transported from land, buried, and accumulated over time in lake and ocean sediment. I then quantify the climate patterns over different time scales, and attempt to understand the relationship between our human ancestors (hominins) and their environment. I also make links with global climate changes to understand the sensitivity of the African environment to changes in solar radiation, greenhouse gases, ocean circulation and temperatures, and glacial-interglacial cycles. The past is the key to the future, and these connections will help us understand how this historically under-studied continent will respond to current and future global warming.
What are your data, and how do you obtain them?
I am an organic geochemist working mainly with leaf wax biomarkers. These waxes (the shiny coating) are produced by plants to protect them from excess evaporation and physical damage. Eventually the waxes are transported to the bottom of a watershed, like a lake or the ocean, and preserved in the sediment. They are preserved because the waxes are comprised of long organic molecules, meaning a bunch of carbon and hydrogen atoms arranged in a row, which makes them resilient to weathering or degradation. Over time the waxes are preserved along with the lake/ocean sediment as it accumulates, and we go and take cores from these archives. We split open the sediment cores and do a long series of geochemical extractions in the organics lab. Finally, I measure the isotopes of both the hydrogen and carbon atoms in the leaf waxes, which are proxies for precipitation amount and plant type, respectively. I then plot these isotope data versus depth or age to understand how the climate changed over time, and do quantitative analyses to understand the cycles, shifts, and amplitudes of variability in the climate system over million-year, millennial, and centennial time scales.
How does your research contribute to the understanding of climate change and evolution?
I study and teach about past, current, and future climate change and the effects of climate change on evolution. Our human ancestors (and other animals) lived and depended on their environment, which was likely driven by natural oscillations in the climate system. By understanding environmental responses to climate, we can test various theories about the link between ecosystems and human evolution. This work gives us a better idea not only of how resources (habitat, food, land use) will change with future global warming, but also what characteristics of climate change human populations are likely to respond to. The rate at which the Earth is currently warming and changing is very important to understand when thinking about the human response, and reconstructing climate change in the past on these shorter time scales is something that I’m interested in focusing on in the future.
What advice do you have for aspiring scientists?
Disseminating your scientific findings is so important. If you put in a lot of work to your research, but can’t let the world know what you found, it’s not helping the public to its maximum potential. I was always such a math/science kid, even through college, and I didn’t realize the importance of being a creative, focused, clear, interesting writer. My advice for aspiring scientists would be to read and write often and to work on these as skills. No matter what scientific profession you end up in, including academia and industry, you will need to write succinctly for a wide audience. But no fear! I used to think I was a terrible writer and I really didn’t enjoy it, but it is something that I’ve practiced and improved upon over time.
Rachel is a postdoctoral research scientist at Lamont-Doherty Earth Observatory. To learn more about her and her research, follow her on Twitter @loopdlupien or visit her website here.
Prolonged Fluvial Activity From Channel-Fan Systems on Mars
by: Gaia Stucky de Quay, Edwin S. Kite, and David P. Mayer
Summarized by: Lisette Melendez
What data were used? In geology, there’s a basic pillar called “The Principle of Uniformitarianism”. It suggests that geologic processes almost always occur in the same manner and intensity now as they did in the past – which is why geologists can look at the rock record to learn more about Earth’s future. In the same vein, many geologic processes that occur on Earth, like landslides, volcanoes, and erosions, can be used to study the same processes on different planets!
This study focused on analyzing pictures of alluvial fans (finger-like deposits that are usually created when running water in arid or semi-arid (e.g., deserts) flows downhill onto a flat surface, as shown in Figure 1) on Mars taken by the Context Camera (CTX) on the Mars Reconnaissance Orbiter (MRO). The scientists also compared Martian alluvial fans to the ones found here on Earth using elevation data collected by the NASA Shuttle Radar Topography Mission. These alluvial fans usually mark the end of a water channel, so they can be used to study ancient water deposits on Mars.
Methods: To study the channels of Mars, the CTX images were converted into digital elevation models, so information like width, slope, and height could be gathered from the data. The valleys on Mars were also measured for how closely they resembled a V-shape. Valleys shaped by rivers have a V-shape, while valleys shaped by other features, like glaciers, tend to have a U-shape.
After gathering all this data, the scientists desired to make an inference about the sediment on Mars, which is too small to be picked up by the camera. So, they turned to places on Earth that had alluvial fans that were very similar to the ones being studied on Mars: the Serra Geral in Brazil, the Great Escarpment in western South Africa, and the Western Ghats in India. These places were ideal parallels for the Martian surface because there’s little to no active tectonic plate movement in the area and the rocks are very well preserved over a long period of geologic time. The big difference is that instead of being placed along mountainsides or plateaus, the slopes that are being studied on Mars are usually along crater rims.
Results: The channels studied on Mars were found to be less concave (curved inwards) and have very steep slopes, indicating a dry environment. The data on concavity and erodibility (likeliness to erode away) on the Martian alluvial fans was most similar to the data found on the South African slopes, which reinforces the idea that the environment was similarly hot and dry.
Why is this study important? This study is another piece of evidence behind the idea that Mars was once full of water, before it underwent serious climate change. Understanding the history of water on Mars is crucial to understanding what conditions are necessary for life to evolve (which can help paleontologists learn about the first life on Earth, too!). It’s also interesting to note how we can learn more about planets that are millions of miles away by looking right here on Earth!
The big picture:More than a billion years ago, water used to run freely on the surface of Mars, creating channels and alluvial fans. Scientists use images of the geologic features that remained after water was no longer on the Martian surface to learn more about the history of the Red Planet and the potential implications for human exploration. Learning more about the surface and climate of Mars is necessary for understanding the hazards and potential resources that would be encountered on a crewed mission to Mars.
Citation: Stucky de Quay, G., Kite, E. S., & Mayer, D. P. ( 2019). Prolonged fluvial activity from channel‐fan systems on Mars. Journal of Geophysical Research: Planets, 124, 3119– 3139. https://doi.org/10.1029/2019JE006167
Since the COVID-19 pandemic began I have attended several virtual conferences. I wanted to give my honest experiences as we head into a still very virtual fall in academia. I think it is also important to consider how long conferences had to create this virtual switch, I will try to be thorough in my reviews.
Each of these conferences was slightly different – different duration, style, format, and user experience. I will try to discuss the pros and cons for each event and also discuss how I managed my time during the events.
Palaeontological Virtual Congress
Dates: May 1-14 2020
Venue: WordPress, virtual
Cost: 5 euros
The Palaeontological Virtual Congress (PVC) is a new (this was the second annual event) event that is completely virtual. They did not have to modify how they were structuring their event due to the COVID-19 pandemic. This event is hosted through a WordPress site and attendees are given login information to explore the different sessions and talks. Talks and posters are updated as mp4 type files and you can view them in your web browser of choice. The entire event is asynchronous and available for a two week period to attendees. This allows attendees to explore content at their own pace and comment on content.
This past year, I participated as a judge of content for the early career researcher symposium. It was relatively easy to navigate through the different content and view talks. There was seemingly no set time requirements for the talks and posters, this allowed users to upload whatever was best for them. Content ranged from 5 to 20 minutes in length. It was really nice to have the two week period to stretch viewing content. However, this is very unlike normal conferences where during this ‘away’ time you are solely focused on the event at hand. It was difficult to give/assign parts of my time to the conference experience. At large, I was still working my normal 8 hours / day.
Digital Data in Biodiversity Research Conference (iDigBio Digital Data)
Dates: June 1-3 2020
Original Venue: Indianapolis, Indiana
New Venue: Zoom
Virtual Cost: $0
The 4th annual iDigBio Digital Data conference was set to take place the first week in June in Indianapolis, Indiana. Event organizers pushed quickly to move into a virtual format. The symposia, discussions, and social events were all hosted through Indiana University’s Zoom account. Registration for the event was done through Eventbrite and each day you were sent an email with the zoom links for the events that day. There was also a thorough Wiki page outlining details, working documents, or discussion docs. This landing page was so convenient! I could bookmark it and return to specific days to explore the talks or pop into other docs of sessions that I missed. The events were largely synchronous with the exception of the posters which were available to view for the duration of the event. In some instances pre-recordings of presentations were (and still are) available to view.
The organizing team had staff in each of the event rooms to help monitor the chat, troubleshoot problems, and ask questions as they were brought up in the Q&A, chat, or Google docs. During this time I had the conference sort of on as background noise while I did regular work – largely easy tasks like cleaning up the database or searching to verify data. For sessions that I was particularly interested in I focused more deliberately on the content. During this conference time I was probably working 6 hour days on average on top of attending the conference.
The conference was structured on a block schedule largely based in EST since that is where the hosts were located. This usually meant there was a morning block, afternoon block, and evening events – which usually included a social event or two. They did run concurrent sessions so in some instances you had to decide which session you would attend. All of this information can still be found on the Wiki page and is worth exploring if you are working to go virtual.
Society for the Preservation of Natural History Collections
Dates: June 8-12 2020
Original Venue: Indianapolis, Indiana
New Venue: Zoom
Virtual Cost: $0
The Society for the Preservation of Natural History Collections (SPNHC) converted rapidly to an online format via Zoom. Similar to the Digital Data conference, they used Eventbrite to send out mass communication daily. This included a schedule of the day’s events, Zoom links to the various session rooms, and other helpful information about the conference.
SPNHC has a longstanding Wiki page with lots of information and the poster presentations were hosted through this same platform. Posters were available for the duration of the conference and all talks and discussion groups were recorded and posted on SPNHC’s YouTube Channel after the conference ended.
In each session at SPNHC, organizers were present to help troubleshoot and help the session chairs with finding and fielding questions in the chat. Talks were uploaded ahead of time via Google Drive and both the slides and a recording of your talk were requested. This was to ensure folks outside of the active time zones could still participate and also those who may not have a secure internet connection. I chose to participate live, the session chair screen shared the PowerPoint slides and presenters would say ‘next’ to carry on through the presentation. If I were to do it again, I would just have the chair play the recording. Giving a live talk on Zoom is very distracting – especially with an active chat room! The chat room notifications, my face, the faces of others, was horribly distracting. I also had much better lighting and sound capabilities on my recordings – so I would urge others to use that route.
During SPNHC, I was probably working half days on my normal work and even during the conference sessions I was watching I was doing simple work on the side managing my database and emailing various people. I only stopped all activity for a committee meeting, my talk, and a session I was running. I didn’t feel horribly burnt out but I did after the week ended. The session blocks were morning and later in the day in my time zone. So I would get ready to start at 8 AM and then sessions went until 9-10 PM some evenings with a large break in the day (which is when I would work). My work-life balance was non-existent this week. I would recommend setting clear boundaries with yourself so that you maintain sanity and get the chance to move around. Being stationary all day can be a huge negative for our bodies and minds!
Know when you need to get up and walk around (wireless headphones can help you here)
Make sure you are staying hydrated
Don’t try to do ‘too much’ talk with your supervisor on how to best manage your ‘normal’ work on top of these virtual events
Set boundaries for yourself
Virtual conferences are different but allow for the participation of so many others – let’s keep working together to create better events to be more inclusive and accessible.
Stay tuned, I am running a session at the Geological Society of America Meeting this year and am attending several other events as we move into the fall semester! Hopefully each event becomes easier and easier on attendees! I am also collating accessibility resources for presenters and will share those in another blog post!
When I was a PhD candidate at UMass Amherst, I was the teaching assistant for our geology department’s Historical Geology class. Every spring, weather permitting, we would take our students on a weekend field trip to upstate New York, to visit rock formations and outcrops that were of Ordovician to Devonian (~450 to 385 million years ago) age. These outcrops and rocks contain abundant fossils, but there was one outcrop in particular that I always found to be the most fascinating: the Middle Devonian rocks exposed near Schoharie, New York.
Now that I am a postdoc at Binghamton University, I’m only about 1.5 hours away from this incredibly cool outcrop! A few weekends ago, my husband and I decided to take a short road trip to go fossil collecting here, as it was the perfect activity to do during a pandemic (limited to no interactions with other people, ample outside time, but also close enough to home). Unfortunately the day was incredibly hot, and we were only able to stay for about half an hour before we felt as if we were roasting. Regardless, we brought home so cool finds, namely a slab of invertebrates, some brachipods, a horn coral, and a sponge!
The outcrop exposed near Schoharie is well-known to local fossil and mineral clubs and fossil enthusiasts. The location is secluded and quiet, there is a long and wide shoulder for parking, and the outcrop itself is set off the road a bit, which is great for students and kids! The outcrop itself is located on Rickard Hill Road, just east of the town of Schoharie.
The rocks here are part of the Helderberg Group, which are composed of limestones that were deposited in a shallow sea during the Middle Devonian. There are three rock formations that are present: the Coeymans Limestone, Kalkberg Limestone, and Becraft Limestone. The Coeymans Limestone is the oldest formation here. It is a medium to coarse grained limestone which is massively bedded, meaning the rock layers, or beds, themselves are quite thick. Fossils are present in this formation, however, because the formation is massively bedded, the fossils are hard to get out of the rock and are less easily eroded.
The Kalkberg Formation lies above the Coeymans, and is described as a thin to medium bedded limestone. This means the individual rock layers within the formation are smaller and not as thick as those observed in the Coeymans Limestone. This formation also contains shale layers, a very fine-grained rock. This formation was likely deposited in a deeper-water setting than the Coeymans Limestone. Several different species and types of fossils are found in the Kalkberg, including animals such as corals, conularia, bryozoa, crinoides, brachiopods, trilobites (which are very rare), bivalves, gastropods, and even straight-shelled cephalopods. When you get out of you car at the outcrop, the Kalkberg Formation is what you are walking on!
The Becraft Formation is the youngest of the three formations exposed at the Schoharie outcrop, and sits atop the Kalkberg Limestone. Similar to the Coeymans Limestone, the Becraft is a more massively bedded, coarse-grained limestone that was likely deposited in shallower waters than the Kalkberg Limestone. Because this formation is more resistant to weathering, it forms the small cliffs at the outcrop location. This formation contains fossils, but again, because it is more massively bedded, the fossils are not always as easily eroded out from the rocks. Other collectors have found fossils such as crinoids, brachiopods, gastropods, and bivalves.
One of the things I absolutely love about the Becraft Formation is that it contains glacial striations at the top of the cliffs! Glacial striations are grooves left in rocks when the glaciers covered much of northern North American about 15,000–20,000 years ago. Striations are commonly found on metamorphic, sedimentary,and igneous rocks, and help geoscientists know which way the ice flowed. But that’s another fun story for later. One of my all-time favorite fossil finds came from the top of the Becraft Formation: a pentamerid brachiopod that was carefully sliced in half by glaciers, that contains glacial striations! The brachiopod was likely preserved as a whole specimen with two valves, much like a clam has two parts to its shell. The glaciers eroded just enough of the formation and brachiopod to cut it perfectly in half. Incredible!
If you are in the area, I highly recommend stopping at the Rickards Hill Road outcrop and visiting the Helderberg Group. Collecting here is fun for all ages, is open to the public, and fossils are almost guaranteed 🙂
What is your favorite part about being a scientist, and how did you get interested in science?
Being a scientist feeds my curiosity for the real world around us. As a climate researcher, I combine natural and societal systems in a social-ecological approach to explore a complex global issue – climate change. The more I learn about the interlinkages of the natural and social systems, the more I realize about their synergies, and the more fascinated I am by the world around us. And the fact that I get to travel to beautiful places definitely helps!
I have been interested in science ever since I can remember. From a young age, I enjoyed learning different subjects, however, science always seemed the logical choice for me. It constantly stimulated my curiosity and interests leaving a thirst for learning more that continues till date. Over the years, science has shaped me to be a logical thinker and problem solver and my love for the subject grows each day.
What do you do?
My research interest lies at the science-policy interface with a focus on climate change, sustainable development, and Small Island Developing States. I am particularly interested in exploring climate adaptation that is synergistic with the broader Sustainable Development Goals (SDGs) of the coastal economies. My dissertation research employs a holistic theoretical lens of social-ecological systems that combines ecological and societal systems with the conceptual frameworks of vulnerability and resilience to guide climate adaptation and sustainable development. To understand these cross-cutting and complex concepts, I use a mixed-methods approach with a combination of quantitative and qualitative methods for data collection and analysis.
What are your data, and how do you obtain them?
I use both primary and secondary data in a mixed-methods approach. For writing my dissertation, I utilized geospatial data, surveys, and interviews combined with secondary policy and planning documents to answer my research questions.
How does your research contribute to the understanding of climate change and the betterment of society in general?
Through my research, I aim to understand the ways how coastal communities will evolve and adapt in the face of future climatic change, particularly, rising sea levels and storm surge. My broader goal is to look for practical and creative solutions for climate adaptation that also supports the sustainable development of coastal areas.
Arsum is a PhD candidate at the University of South Florida. To learn more about her and her research, head to her website here.
Triassic vegetation and climate evolution on the northern margin of Gondwana: a palynological study from Tulong, southern Xizang (Tibet), China
by: Jungang Peng, Jianguo Li, Sam M. Slater, Qianqi Zhanga, Huaicheng Zhu, Vivi Vajda
Summarized by: Kailey McCain
What data were used? Researchers noticed that while there was extensive research in North American and European paleobotany (i.e., plant fossils) from the Triassic period, data was very limited for Southern Asia. To fill this gap in knowledge, 147 samples were collected across China and examined for pollen, dust, and other microscopic fossils (also known as palynomorphs). Additionally, rock samples that dated through the Early Triassic were collected and processed.
Methods: The samples were processed using hydrochloric acid (HCl is strong acid and has a low pH value ~1) and hydrofluoric acid (HF is a weak acid and has a higher pH value ~6) lab techniques. By using these acids, the microfossils were isolated from the sediment sample and placed on a microscope slide for further investigation.
The palynology samples were tested for pollen and spores (cells that are capable of developing into a new individual without another reproductive cell). The abundance of specific species were then mapped to illustrate vegetation and climate during the Olenekian, a period of time during the Early Triassic. The identified microfossils can be seen in figure 1.
Results: The data collected showed that there are roughly three vegetation stages throughout the Early Triassic. The first stage is dominated by pteridosperms (fern-like vegetation lacking spores), which indicated a warm and dry climate. The following stage exhibited a decrease in pteridosperms and an increase in conifers (woody plants). This change in vegetation indicates a decrease in temperature and an increase in humidity. The final stage exhibits a steady increase in conifers and a diverse range in ferns, thus indicating a stable and temperate climate.
Using these stages, researchers were then able to compare the shifts in vegetation and climate to the tectonic activity due to the rifting (splitting) of Gondwana, an ancient supercontinent that split from Pangea. Through the examination of the rifts and ocean levels, the researchers hypothesized that the separation of Gondwana was a driving factor in regional climate and vegetation shifts.
Why is this study important? This study provided insights into the ways tectonic activity affected the environment in an area that lacked prior research. It drew important correlations between climate and tectonic activity. Additionally, evaluating the specific abundance and lack of certain vegetation helps establish evolutionary patterns not only in the Triassic, but also in supercontinents.
The big picture: Paleobotany and palynological data paint a great picture of what Earth was like during certain time periods. Specifically, the data collected in this study shows a correlation in Triassic vegetation and climate evolution during the rifting of Gondwana in Southern Asia.
Citation: Triassic vegetation and climate evolution on the northern margin of Gondwana: a palynological study from Tulong, southern Xizang (Tibet), China. (2019). Journal of Asian Earth Sciences, 175, 74–82. https://doi.org/10.1016/j.jseaes.2018.06.005
I work as a Systems Engineer at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. My job is very interdisciplinary but generally revolves around operating rover missions on Mars – the ultimate remote work experience! I’m involved in two Mars rover missions: the Curiosity rover and the Perseverance rover. Curiosity has been on Mars since 2012 and is still going strong! I help make decisions about what the rover is going to do, for example: where to drive to, what to take photos of, what to shoot the laser at. Being able to see brand-new, never-before-seen images of Mars is by far the best part of being on the Curiosity team!
The Perseverance rover is NASA’s latest Mars rover that is scheduled to launch THIS summer and land on Mars in February 2021. We are very busy making preparations for surface operations for when Perseverance lands on Mars. This involves a lot of rover hardware testing to figure out how the rover will drill and collect rock and regolith samples. We’re also busy training the science team to be able to operate the rover smoothly once it lands. To do this, we’ve had a few field training exercises to simulate the rover operations procedures. Rover teams are made up of hundreds of scientists and engineers from all over the world, so teamwork and communication are the most important factors in making NASA missions successful.
Since we can’t send people to Mars just yet, sending car-sized rovers is the next best thing to help us get closer to answering fundamental questions about the Red Planet: Did Mars host environments that may have supported life in the past? Did life ever evolve on Mars? How has Mars’ climate evolved over time? What can the geologic rock record on Mars tell us about ancient environments and how they’ve changed over time? How can we prepare to send humans to Mars?
I first became interested in science and NASA when I was in high school and had the opportunity to attend Space Camp in Huntsville, AL. A lifelong athlete, I really enjoy teamwork-oriented jobs, which is why jobs in mission operations have always appealed to me. My advice to young, aspiring scientists would be that if you find something that truly inspires you, pursue it! Meet new people, ask questions, and never stop exploring!
Follow Rachel’s updates on her website, Twitter, or Instagram! Another website folks might be interested in: NASA’s Mars exploration website. It’s frequently updated with rover mission updates and has tons of info about past, present, and future missions to Mars: https://mars.nasa.gov/
Experimental evidence for species-dependent responses in leaf shape to temperature: Implications for paleoclimate inference
by: Melissa L. McKee, Dana L. Royer, Helen M. Poulos
Summarized by: Mckenna Dyjak
What data were used?: Four species of seeds from woody plants were used: Boxelder Maple (Acer negundo L.), Sweetbirch (Betula lenta L.), American Hornbeam (Carpinus caroliniana Walter), and Red Oak (Quercus rubra L.). Three species from transfered saplings were also used: Red Maple (Acer negundo), American Hornbeam (Carpinus caroliniana Walter), andAmerican Hophornbeam (Ostrya virginiana K.Ko(Mill.)ch). The types of species were chosen because they each exist naturally along the east coast of the United States and have leaf shapes that vary with climate.
Methods:The seeds and saplings were randomly divided into either warm or cold treatments. The warm treatment cabinet had a target average temperature of 25°C (77°F) and the cold treatment cabinet had a target average temperature of 17.1°C (63°F). After three months, five fully expanded leaves were harvested and photographed immediately. The images from the leaves were altered in Photoshop (Adobe Systems) to separate the teeth (zig-zag edges of leaves) from the leaf blade (broad portion of the leaf). The leaf physiognomy (leaf size and shape) was measured using a software called ImageJ. The measured variables were tooth abundance, tooth size, and degree of leaf dissection. The degree of leaf dissection or leaf dissection index (LDI) is calculated by leaf perimeter (distance around leaf) divided by the square root of the leaf area (space inside leaf). The deeper and larger the space between the teeth of the leaf, the greater the LDI.
Results:The leaf responses to the two temperature treatments are mostly consistent with what is observed globally: the leaves from the cool temperature treatment favored having more teeth, larger teeth, and a higher LDI (higher perimeter ratio). However, it was found that the relation between leaf physiognomy (leaf size and shape) and temperature was specific to the type of species.
Why is this study important?: Paleoclimate (past climate) can be determined by using proxy data which is data that can be preserved things such as pollen, coral, ice cores, and leaves. Leaf physiognomy can be used in climate-models to reconstruct paleotemperature from fossilized leaves. This study supports the idea that leaf size changes correlate with temperature change. However, the responses varied by species and this should be taken into account for climate-models using leaf physiognomy to infer paleoclimate.
The bigger picture: Studying paleoclimate is important to see how past plants reacted to climate change so we have an idea how plants will respond to modern human-driven climate change.
Citation: McKee ML, Royer DL, Poulos HM (2019) Experimental evidence for species-dependent responses in leaf shape to temperature: Implications for paleoclimate inference. PLoS ONE 14(6): e0218884. https://doi.org/10.1371/journal.pone.0218884
Not long ago we were invited to talk about Time Scavengers with our friends Gabe and Brittney who are staff at the Raymond M. Alf Museum of Paleontology and the Western Science Center, respectively. Every Friday for the past few months Gabe and Brittney host two chats with folks about their research and educational projects! These discussions start with a brief presentation explaining science or projects or ideas to the audience as it is streamed live on Facebook. Then Brittney collects audience questions and we have a discussion at the end of the talk!
We talked about different aspects of Time Scavengers, most importantly the three foundations for which our site is built upon: Science Literacy, Science Identity, and IDEA+J (inclusion, diversity, equity, accessibility, and justice). We also discussed briefly what we have done so far and what we would like to accomplish in the future! If you are interested in learning more please check out our slides by clicking here or watch the full presentation as it is still available on Facebook by clicking here.
It can be tricky giving a talk with two people, but we made it work! We met a few times before our presentation date with Gabe and Brittney. The first few meetings were to outline the talk and decide on what information we wanted to share and how to structure that information. Then, we began to build the slides. This is always the fun part, as we get to look through our data and pick out fun graphics and images of ourselves and our team. Lastly, we went through and decided who would present which sections of the talk. Jen did the introduction, we both talked about our backgrounds, then Jen continued to discuss the more in-depth introduction slides and overview of Time Scavengers. Adriane then talked through the Science Literacy section, Jen the Science Identity section, then Adriane presented the IDEA+J section and our future goals slide. Lastly, Jen wrapped up the talk with our acknowledgements slide. We think this worked quite well, as we both were able to split the talking time. The questions our audience members asked were excellent, and really made us stop and think! We had a ton of fun throughout the entire process, and very much appreciate the opportunity Gabe and Brittney gave us to talk about Time Scavengers and share our love of science communication!
To take a deep dive into different paleontological concepts, the Time Scavengers team is starting to conduct interviews! We start with a list of questions that we share ahead of time with our speaker and then we move with the flow of the conversation. Our first interview was on ichnology, or the study of trace fossils, with Dr. Tony Martin.
Ichnology focuses on studying the preserved behaviors of animals in the fossil record. These behaviors can look similar and quite different throughout time and play an important role in understanding past and future environments here on Earth. Tony, Adriane, and Jen chat through various ichnological topics, explore SciComm, and there is even some surprise dancing!
We touch on the idea of ichnofacies and their importance in unraveling the complex history on Earth. If you are interested in learning more about how groups of ichnofossils can tell us about ancient environments here are some links:
Jen: Hi everyone! Thank you for tuning into Time Scavengers’ first interview. Today we are talking about ichnology with Dr. Tony Martin. Dr. Adriane Lam and I will be conducting this interview. Tony is a professor at Emory University and an author of popular science books surrounding ichnology, the Georgia coast, and the intersection of the two. Join us as we chat about what ichnology is, how Tony became an author, and there may even be some surprise dancing near the end.
Adriane: I’m Adriane Lam from Time Scavengers and I’m here today with Dr. Jennifer Bauer and Dr. Tony Martin and we’re going to be talking with him about ichnology. So hello, Dr. Martin!
Tony: Hello! And I am so happy to be here to talk about ichnology because I consider myself an ‘ichno-evangelist’ and I’m ready to convert everybody to the Church of Ichnology. Which has a holy trinity: substrate, anatomy, and behavior. Amen, sisters!
Adriane: I love it! I’m sold. So let’s start off by just talking about, for those who are listening who are unfamiliar maybe, what is ichnology?
Tony: Ichnology is the study of traces, tracks, trails, burrows, borings, tooth traces, gnawings, anything that an animal, or a plant, can leave on a substrate that shows its behavior. And that’s really important to the difference between, say, a trace and a drag mark of a stick going along the bottom of a lake. The latter is not a trace because it’s not behavior. There has to be behavior. And that’s what I really love about ichnology is that it reflects behavior. You can actually tell what an animal was having for lunch 500 million years ago, through ichnology!
Adriane: That is so cool and very interesting. So, I’m a big fan of ichnology, um, obviously I am a big fan of coprolites, I think they’re just the coolest things ever!
Tony: Coprolites are the best!
Adriane: They are so cool! So for those that are listening coprolites are fossil poop, and they come in a variety of shapes and sizes, as you well know Tony. But, you know, a lot of paleontologists study coprolites but also these other trace fossils to get a sense of animal behavior through time. So why is it important that we study this animal behavior in the geologic past?
Tony: What’s great about trace fossils as a way of looking at animal behavior is trace fossils oftentimes are in the same place where the tracemaker was living. So this gives us insight not just of the behavior of the plant or animal that was making these traces at that time, but the place. And it tells us how that animal or plant was interacting with its environment. For instance, if an insect walked across a Permian dune 260 million years ago, we can look at that and say ‘that insect was walking across a dune’. We don’t just say ‘yeah, there’s an insect and it was walking’. We know something about the environment and the context of the environment in which that insect was living. So that gives us kind of a snapshot of behavior that was happening in the ancient past related to the bigger picture of how that trace maker fit into its environment.
Adriane: So what is your favorite trace fossil then, and why?
Tony: That’s kind of like asking a parent what’s your favorite kid. It’s a tough one to narrow down. One I picked out that I always like to point to is a study I’m very proud of published about 10 years ago in PLOS One, was about a fish trail. Where the fish had swam along a lake bottom in Wyoming about 50 million years ago. This fish, when it swam along the lake bottom, first of all it showed there was enough oxygen at the bottom of that lake for that fish to be there, to be swimming in the first place. But it left fin marks, and the fin marks, I’ll try to do it with my hand, the fin marks kind of made these double sine curves. So those were from the pelvic fins. Then there was the caudal fin. The caudal fin was doing a bigger sine wave. Then it had a smaller anal fin that was on the bottom of the fish, and it was leaving a smaller sine wave. In the middle of all those traces were these little ‘pop pop pop’ pock marks made by its mouth. That’s when I looked at this trace fossil I think in 2008 was the first time I saw it, and I was like, ‘it was feeding!’. It was feeding along the bottom of the lake. And there was only one fish in this formation, the Green River Formation from Wyoming that had a mouth that pointed down. And that was Notogoneus osculus. So I knew which fish made it, what it was doing, when it was doing it, it told me about the lake like I was saying earlier, you have it in the context of its environment. And using a little bit of math, we were able to figure out how big it was because the sine waves told us a bit about, uh, putting it into a formula that told us how big it was! This is the one that got away, and it was this big.
Adriane & Jen: Whoa!
Tony: That was 50 million years ago! That’s a pretty darn good trace fossil. So yeah that one’s my favorite I think.
Jen: So, I have kind of a follow-up question. So that one is kind of easier because we can watch how modern fish behave and make interpretations based on the fossils and kind of match up the different fin types and think about movement, but not all animals have these modern comparisons. So how do you interpret trace makers when things are maybe a bit murkier.
Tony: Oh boy, yeah, that’s a tough one. So there are ways we can, we can look at something like a sauropod dinosaur; those sauropod dinosaurs, we don’t have anything like that alive today. The biggest elephants we have today are maybe around 7 tons. Some of these sauropod dinosaurs may have been more than 50 tons. So we have no modern analogues for anything like that. In that case, we have to look at, through maybe computer modeling, or experiments, to look at weight loading, and other ways that we can mathematically predict ‘here’s what those traces should look like’. But then again we also have the trace fossils themselves. So we have sauropod tracks, and we have traces made by other animals that there’s no modern analogue whatsoever. So there we have to be really good detectives. We have to look at what was left by the animal that was a part of its behavior but also taking into account that this behavior may be unlike anything we have today. It’s a really tough problem for when we don’t have the exact modern analogues, then we have to use something that’s close enough. Does that kind of answer your question? It’s a really tough one to answer, especially when we get into really big animals.
Adriane: And I kind of have a follow up question to that as well. And I don’t know if a lot of people listening are aware that when we name these ichnofossils, we don’t name them after the animal, right? And, can you just elaborate why that is, and I think you pretty much touched on that but just to restate it.
Tony: Yeah, there’s a little rule in ichnology is that one tracemaker can make many traces. Related to that then, you can also have many different tracemakers, many different species of tracemakers, can make very similar looking traces. So if you started naming trace fossils after the tracemaker you think made it, mmmm, you might be wrong. If you start naming trace fossil based on, well I think a variety of different tracemakers made it so I’m going to put all their names in the name, that’s not going to work either. So what we try to do with naming trace fossils is base it on consistent form. So if we see a trace fossil that has a form and it occurs in a substrate, such as sand or mud or wood or stone, if it occurs consistently in a particular kind of substrate then we give it a name that’s consistent. One example I can think of, for instance, is Ophiomorpha nodosa. ‘Ophiomorpha’ refers to it’s snake-like form, because when these were first named, they looked kind of snake-like. The ‘nodosa’ part refers to little nodes, and these are fecal pellets, well not fecal pellets, but pellets that were put on the side of the wall of these burrows. These were actually burrows made by crustaceans similar to, say, modern ghost shrimp, that makes this form Ophiomorpha, and then it has these nodes, nodosa, that I can say to another paleontologist, say in Poland, or Czech Republic, or China, I can say Ophiomorpha nodosa, and I just communicated what that trace fossil is and what it looks like. Without going into ‘well it’s kind of snake-like, and it branches, and it has little nodes’. That would get lost in translation pretty quickly.
Jen:Ophiomorpha is one of my favorite trace fossils!
Tony: As it should be! It’s a gorgeous trace fossil.
Jen: That brings up a question that I’ve had as a museum professional. So a lot of my work recently has been database management, and the taxonomy of ichnofossils is a very hard thing to reconcile. And the way that databases are kind of structured are in like a hierarchical model, so similar to Linnaean taxonomy. So I have essentially a tree that’s my taxonomy tree, and I have bins that I can bin the different types of animals into, but I’ve kind of just put ichnofossils as a phyla, and that’s what I’ve seen done in other databases. But, do you have advice for people who have this problem, like me?
Tony: Huh, yeah, short answer: no. And it’s funny because I’ve sometimes been labeled by my ichnological colleagues as a ‘hyper-lumper’. In paleontology, we have lumpers and splitters, and this is very useful because, of course there are people in between; I guess that would make them splitters, hmm? Ok but yeah, with the people in between they say ‘well, sometimes we need to lump in these different names that are really the same fossil’. The splitters say ‘no, we actually need to have a lot of different names’. I’m more of a lumper in that, does this trace fossil show these 3 or 4 characteristics? Then OK, let’s call it that ichnogenus. Ichnospecies, then I start going ‘oohhhh, no no no’. I don’t necessarily want to do ichnospecies. But I understand if some of my colleagues, again for communication purposes, start classifying them differently. For your purposes, for putting them into a database, in a museum collection, it’s probably best to do at least the ichnogenus if you can. That at least narrows it down. Then, I would hand it over to the experts who know more about how do you split it from there in that ichnogenus. So for instance, Ophiomorpha is an ichnogenus. Under that, you can have, gosh, I think I’ve seen 4 or 5 ichnospecies. And I’m only going to name nodosa because people get annoyed and get in arguments after that. Does that kind of make sense?
Jen: Yeah, I’m having more of a problem with everything in between. So I have a phyla, or phylum, and I have ichnogenera and whatever is underneath them. But the in-between is just empty.
Tony: Yeah, so for example, I have a cast of a dinosaur track here, that I’m going to hold it up next to my head. And it’s um, I bought it, it’s an epoxy resin cast that was taken from a real dinosaur track, there you can see some of the 3 dimensions of it. I think it was labeled as Late Triassic, and it was Grallator. So Grallator is the ichnogenus we give to that dinosaur track. Then the people who study dinosaur tracks, they can communicate with one another by saying ‘Grallator’. They have ichnospecies under that. Now me, I see that and go ‘Ah, that’s a therapod track!’. And I might write down ‘Grallator, question mark’, and leave that up to the experts to classify further. ‘Therapod’ is an interpretation, so then I’m interpreting this dinosaur track, I’m interpreting this as a dinosaur track. Leaving open that it could have been made by another animal, though. That’s a hypothesis. But the name we give is based on the form, the form of the track. And that leaves it open for the possibility that something other than a therapod dinosaur made it. How’s that for an explanation?
Adriane: So do you want to move on to talking about your book and your science communication?
Tony: I would love to, yeah! So I’ve been, oh, since 2013, I started writing books. I’d written a few books before that, but 2013 is when I published this big thick book called ‘Life Traces of the Georgia Coast’. It’s more of an academic-y book, but I wrote it for a general audience too; for people who are naturalists, interested in, when they go down to the Georgia coast, and they’re on the barrier islands, they see burrows, they see tracks, or other traces, and they go, ‘hmm, I wonder what that is?’. So it was a book to answer those questions, but also something that my academic friends in paleontology could use. It was published by Indiana University Press and part of their Life of the Past series and their paleontology books that Indiana Press puts out. So I was really proud to do that. Then I started following that up. In 2014 I did ‘Dinosaurs Without Bones’, here’s the paperback version right here. That beautiful cover by the way, the cover art is by paleoartist Peter Tressler, he’s an Australian paleoartist, so you should look up his work. That was about the concept of, what if every dinosaur skeleton disappeared tomorrow? Every dinosaur bone vanishes; how would we even know dinosaurs existed? And I was like, well, fortunately we have trace fossils! So the book is about that, and I wrote that overtly for popular audiences. It’s a trade book, but it has a lot of references back for, again, for my academic friends if they wanted to learn more from that. I followed that up in 2017 with ‘The Evolution Underground’. And the subtitle is ‘Burrows, Bunkers, and the Marvellous Subterranean World Beneath Our Feet’. The subtitle should have been ‘How Burrows Change the World’, but Malcolm Gladwell probably would have sued me. Ah, with that, I want you to think about how burrows helped animals survive, especially mass extinctions, and then how burrows changed the world in marine environments, terrestrial environments, all environments, and actually changed everything. Kind of a big-picture book. That was a fun one to write! Now my newest one is ‘Tracking the Golden Isles’, and this is again a trade book meant for a general audience, it’s more about a specific place. So the subtitle you see is ‘The Natural and Human Histories of the Georgia Coast’. So it’s returning to the Georgia coast, but I wanted to give more of a view for people who live here in Georgia, as well as outside of Georgia, of how traces give us stories. That there are stories written in the sands, in the muds, in the bones, in the driftwood, that we see that tell us what happened in this place, then give us insights on how humans and other organisms interacted with those places through time. So this is part of my ichno-evangelism, I want to teach people about traces and why traces matter.
Adriane: Perfect. So a follow up question to that is: You’re a scientist and you are trained as such, just like Jen and I are, and through grad school, we learned how to do science writing, we publish these journal papers. How did you transition, and teach yourself, how to write for a scientific audience, um, or transition from writing for a scientific audience to a more general public audience? Was that something you practiced over the years? Is it self-taught? Because, it’s a, it’s a hard skill to learn.
Tony: Yeah, you’re, yeah I agree one-hundred percent; it’s a hard skill to learn. And in the case of people who are trained to write academically, there’s some un-learning to do too. That we are oftentimes rewarded with our scientific writing, to be as technical as possible and use a lot of jargon. So there was, in my writing process, I had to un-learn. This is where I thank my students, because for years at Emory, I taught non-science majors. And I still do sometimes. But non-science majors, I had to strip out the jargon in my teaching. So there was part of that training I think in the classroom, being able to clearly communicate different scientific concepts, particularly in geology and paleontology, that would translate well to people who are non specialists. Then if you can do that on the page, if you can write on the page, then that helps too. Here’s where I credit blogging. So I started blogging in the late two thousands. That was writing I did, then through practice for a general audience. That’s also how I got more of a, what we call, an author voice. I started finding my voice as an author and a distinctive style. I didn’t want to be, say, like Stephen Jay Gould, or Pat Shipman, or some of these other writers who I really admire. That I read their writing and I go, ‘Oh, I love their writing! I’m going to write exactly like them’. I needed to find my own voice. I think after about four to five books, I have found that voice. But it came through teaching first, and then blogging, and writing, really getting into a daily practice of writing, however small. Two-hundred and fifty to five hundred words a day, that’s my typical book-writing regime. I just try to do a little bit everyday, and then when you do the math, it adds up. Next thing you know, over the course of a year, year and a half, you have a book! And that’s where the editing comes in. That’s part of the process too.
Adriane: So can you tell us a little about the editing process. Because, Jen and I, you know, we blog, and that’s mainly what Time Scavengers is; we have a lot of blogs. But we’ve never written anything as substantial as a book, and we know that the peer review process and editing process for a paper is much different from a book. But can you kind of walk us through that process, what is it, how long does it take?
Tony: Yeah, and writing a book, especially for a general audience, I oftentimes, I will write it first, without criticisms, self criticism. So I have to put duct tape over my mouth, silence my inner critic, and just ‘zzzzzzzz‘. You know the GIF of Jim Carrey doing that? Ok so I do that, I just type, I put down the words, then I set it aside. Later, I’ll come back to it and then I’ll go through it and edit it. Sometimes along the way I’ll self-edit. But usually I just set it aside, come back to it, and then go through and edit. My favorite way to edit for a trade book is actually, I’ll print it. I know, poor trees. But I do recycle. I’ll print it, and I’ll hand-edit. That’s actually my favorite way to edit. In my most recent book ‘Tracking the Golden Isles’ I was so grateful that University of Georgia Press actually did send me a printed copy of the page proofs and I went through and I hand-edited through those page proofs. So the editing process is multi-layered, it’s multi-stepped. Once I’ve gone through it in a way that I think it’s pretty good, and I’m not embarrassed, then I’ll hand it over, say, to a copy editor or other peer reviewers. And actually, my last four books have been peer reviewed as well, or I’ve had other experts read the book, look for factual content, as well as how well does it read. Does it read, does it read okay? ‘The Evolution Underground’, for instance, I think the peer reviewers I had on that were Sally Walker, Dr. Sally Walker, and Dr. Patricia Kelley. They were really good peer editors, being able to look at it in terms of content, but also, did it make sense. And they also are fantastic teachers, so I really trust their instincts on, ‘did this sound good enough that a, someone who’s not an expert will get what I’m writing about?’
Adriane: That’s awesome. Do you also get, during this process, do you have other friends that are non-scientists read the book?
Tony: Oh, yeah, absolutely! And I’m really glad you mentioned that, because ‘Life Traces of the Georgia Coast’, the people who actually read that book first were non-scientists. I was in a small writing group at Emory, and there were just three of us. One of them, you’ve probably heard of her, she’s famous: Isabel Wilkerson. She wrote this absolutely fantastic book that should be required reading of every American. It’s called ‘The Warmth of Other Suns’. It’s about the great migration of African Americans from the South to the North. And she tells it through three different people. She was in our writing group, and she’s a Pulitzer Prize winner, who’s writing this award-winning book and the other member of our group, Christine Ristaino, she was writing a book that was about more personal, more about personal traumas, that she had had happen in her life. Three very different books, three very different people. We got together once every two weeks or so, over the course of two years, we read our writing to one another. Which I now do in our classes when I teach my students writing, I have them do that as an exercise: read it out loud to one another. When you read it out loud, as an editing process, and that person reading your work out loud, that’s right, hand it to the other person, they read your work out loud and they’re not an expert in your field. They’re going to find where you’re unclear. They’re going to stumble over your words; they’re going to go ‘rrmmmrrm, uhhh, what, Ophio-what?’ And they’re going to help you find how to make it better. So I am forever grateful to Isabel and Christine for being in this group with me, where they really taught me to be more clear with my writing for people who are non-experts in my field. Yeah thanks for asking that, that’s [chuckles].
Adriane: Yeah of course. But with Time Scavengers, we have an editor, and she is not trained as a geoscientist, and you know, her feedback for us is invaluable for us too, and we owe her a lot too for saying..
Tony: Absolutely. Yes.
Adriane: … ‘what are you talking about?’ Yeah, it’s, it’s such a critical part of science communication that I think a lot of scientists don’t realize, is getting outside of your science circle, get in touch with your friends, and hand them something and say ‘Does this make sense?’ And I’ve even had my mom email me and say ‘I don’t know what you’re talking about in this blog, fix it!’
Tony: Right, right, yeah isn’t that perfect?
Adriane: I love it!
Tony: Even if your mother has a PhD in some other science, she might read your blog and go ‘Oooh, I didn’t quite get that?’ So that, that really helps when you have somebody from outside of your field helping you. And especially the non-scientist, people who may be experts in whatever field, political science, or sociology, if they can read your blog and go ‘Oh yeah, I get it!’, then that’s a high compliment. It means that you’re using a minimum amount of jargon and you’re using it in an engaging way, hopefully with a good narrative structure too. That people are following a story along the way.
Adriane: Exactly. And you touched on something that I think is really important too when we’re doing science communication, is storytelling. When you’re writing your book, do you keep this in mind, that you want to write it as a story? Are you trying to bring people in, and then bring them along on a journey with you; do you think that’s the most effective way to do this?
Tony: Yes, I do. And there’s a class I teach at Emory that, uh, I’m going to be teaching it every Spring, I’ve taught it three times now, called ‘Environmental Science Communication’. In that, I work with them on narrative structure, making sure they have some sort of narrative structure. Now what’s that? The very simple way to do this is how Randy Olsson, science communicator, has written several books on this. He uses uh, he calls it the ABT: the And, But, Therefore Framework. So that’s something I work with the students [on] and we experiment with it. We test it throughout the entire semester. We’re good scientists while we’re doing our communicating! And this ‘And, But, Therefore’ is that we give information, so ‘I was following these tracks, they were in the sidewalk, preserved in the cement, BUT I’m not sure what animal made them?’ Suddenly I’ve created some dynamic tension in that story. ‘BUT I don’t know what made them’: Now there’s a mystery afoot. Ah! ‘THEREFORE, I need to come to some conclusions towards the end to resolve that, I can’t just leave the audience hanging. There has to be some way, then, to carry on the narrative. So the ‘And, But, Therefore’ as a framework works really well, then, for me to hang my stories. That I make sure that when I’m writing that, and oftentimes I start the chapters in my books with a, with a little story typically told in the field. That structure helps me, keeps me on track, pun intended, to keep the narrative structures so that the reader is going to be engaged and interested. The deadliest mistake we make is when we do the ‘and and and’. ‘And then I looked at the tracks, and then I saw it had four toes, and then I saw it had claw marks, and then I looked at the heel…’ Oh my gosh, you are snoring already! Just stop, kill me! You want to make sure you have some sort of structure there, and you’re not doing the information overload.
Adriane: That is excellent advice and so true. So, just to finish wrapping up talking about your book, where can people find your book if they wanted to go and read these and buy them? Are they available online?
Tony: Oh I’m so glad you asked that! So ‘Tracking the Golden Isles’, what’s great right now, go the University of Georgia Press website. They have a coupon code there. You can get fifty percent off! Can’t find a better deal! So do that, don’t, don’t buy it through that thing, ya know, that Amazon… Instead, go save yourself fifty percent, go the University of Georgia Press website, U-G-A Press dot org, go there, the coupon code is there, look it up, use the coupon code. And that’s good until the end of June. They did it in may, they’re going to do it in June. Now my other books, you can get them, those, look for those through, there’s a website indie bound dot org. I-N-D-I-E, indiebound.org, that you can look up your nearest independent bookstore. Because right now, with the pandemic still going on, independent bookstores are having a really tough time. I LOVE independent bookstores. So what you can do, is uh, I think you can just put in your zip code, and that will tell you the nearest independent bookstore, order the books then through those bookstores. What’s great is now ‘The Evolution Underground’ is available in paperback, so you can save some money there. And then, same with ‘Dinosaurs Without Bones’, also in paperback. So you can save money there. And then some people prefer either on Kindle, or Nook, or other e-readers, you can get your e-version as well. And occasionally there are good sales on those. So wait for the sales, too. Because I want people to save money for important things, like pizza and beer.
Adriane: Very important things.
Jen: I’m sure they’re also available through, like, public libraries.
Tony: Absolutely! Yes! Yeah, I’m always happy when somebody says ‘hey, look what I found at my library!’ and they post a picture on Twitter. I’m like, thank you, I love hearing that libraries have my books too! So if your library, your public library, does not have my book, then please persuade them to get them. But do it quietly, you don’t want to get shushed.
Adriane: So we have three more questions we were going to ask, just getting into more of the ichnology side of things, and traces and tracks. Um, so the other question we have for you, along the lines of ichnology is, sometimes traces are found within or around other fossils that can tell us a compelling story from a snapshot in time. Can you tell us about one such trace fossil?
Tony: Yeah, one that comes to mind is, I was working with a group from Indiana University Fort Wayne, and it was Jim Farlow working with the group. They were studying dinosaur tracks in Dinosaur Valley State Park, outside of Glen Rose Texas. It’s a world famous track site. I was there of more of the invertebrate ichnologist, where I was looking at the invertebrate burrows that were associated with the dinosaur tracks. So there were these U-shaped burrows that, we give them the ichnogenus name ‘Diplocraterion’. It’s a mouthful, but, people who know it know what it is. Those were associated with some of the horizons below where the dinosaur tracks were. But there was one place where a dinosaur actually stepped on one of the burrows. So this brings in the question: Did that dinosaur step on the burrow while there was a little, say, crustacean, inside the burrow. And I think the answer is ‘no’. The reason being it looked like the burrow was barely compressed. And this was a big therapod dinosaur that stepped on it. It probably weighed at least a ton. It should’ve compressed it more had it had been muddy and it had been squishy. This tells me that the invertebrate burrow, with the dinosaur track, tells me something about aaahhhhh, that burrow was probably long abandoned, its maker was probably dead, maybe for decades, then it was buried, then it was emerged, and this dinosaur stepped on it while it was a firm ground. While it was firm, and not muddy. This is the way you can tell sometimes the gap in time between trace fossils; that despite they’re being together, doesn’t mean they were there at the same time. This also gets you thinking about how these gaps in time, trace fossils are sometimes valuable for us to be able to figure those out. Another example I’ll give you is, again using dinosaurs, is thinking about dinosaur bones. I wrote about this in ‘Dinosaurs Without Bones’, that, I cheat a little bit, I do talk about dinosaur bones in it, but there are bones that have tooth marks in them. Tooth traces where another dinosaur chomped on the dinosaur. So I think Stephanie Drumheller and Julie McHugh, for instance, published a paper recently about this with Allosaur tooth marks. Those tooth traces, then, tell us that the dinosaur that was being eaten had to have been dead, because to get through all that meat, to get down to the bone, it wasn’t just sitting there, saying ‘yeah, ok, you got down to my bone’. It was dead. So this tells us again a little bit about the gap in time between when did a dinosaur eat another dinosaur but also what dinosaur ate another dinosaur. These are ways that you can take trace fossils, put them together with other fossils, and be able to figure out some of the relationships between these different organisms, and sometimes at different times. How’s that?
Adriane: That’s really cool!
Tony: Yeah it is!
Jen: I think that is also really cool because Adriane and I used to collect Diplocraterion in the Ordovician, um, and you’re talking about a much younger example. So just thinking about the same shape burrow, maybe different tracemakers, maybe very different tracemakers, given hundreds of millions of years in between. But that’s, that’s a really cool thing I think about ichnology, is that maybe is lost a little bit on people.
Tony: Thank you for mentioning that because I actually got my start as a paleontologist in the Ordovician. I did my master’s thesis work in the, uh, in the Cincinnati region, I went to Miami University.
Jen: All of us did, that’s awesome!
Tony: The ‘real Miami’, as I like to tell people. Miami was a university before Florida was a state, they had the t-shirts there. But what was great were the trace fossils there, a lot of those trace fossils that I saw then, again, yeah, like you said you can see some of the same ichnogenera in rocks of much younger, much younger rocks, geologically speaking. The Ordovician, more than four hundred million years ago, and then the ones I was talking about from Glen Rose, those are a mere ninety-five million. Yeah, those are baby traces compared to the Ordovician. So yeah, that’s pretty cool that we can look at these trace fossils then, and we can think about the very different animals that would have made those very similar-looking trace fossils, maybe representing the same behaviors, and behaviors that are repeating through time.
Jen: I had kind of a wild-card question. So I remember taking Ichnology, uh, with Dan Hembree at Ohio University, and we got on the topic of eggs, and are eggs trace fossils. Because technically there’s some sort of biomineral, but technically they’re not a hard part of an animal. What are your feelings on this?
Tony: Oh, I, I don’t just have feelings, I have certainty!
Jen: [laughing] Okay!
Tony: Eggs are body fossils. They’re body parts. This is one of my favorite quiz questions, test questions for my students. So any Emory students that are going to be taking my classes, you’re learning this now. Any that have taken my classes, they’ve already learned this. Eggs are body parts because it’s an extra body part for the developing embryo. So the eggshell itself, it’s like a body part. Same with a, uh, same with a pupa, for instance. And because you had classes from Dr. Hembree, he’s into insect traces. So a pupa, pupal case, is a body part of that insect, of that, of that insect as it’s developing. A cocoon that’s preserved as a fossil that shows the actual silk weave, that’s a trace fossil.
Tony: Yeah. So eggs, what’s also cool though is that there are trace fossils of hatching windows, of where a little baby dinosaur poked its head out of the egg. That hatching window, that’s a trace fossil. If you had an egg, that a dinosaur stepped on it, that would be a trace fossil of the dinosaur stepping on the egg. If you had, uh, the old stereotype of the mammal eating an egg, if you had those tooth traces in the eggshell, that would be a trace fossil, but of the mammal. So you can have trace fossils in the eggs themselves, but the egg, eggshell, that’s [not] a trace fossil.
Adriane: Well I learned something new!
Tony: Yeah, there you go! Now, just to complicate it even more though, if a Troodon, which was a therapod dinosaur in the Late Cretaceous about seventy-five million years ago, its eggs are paired. So it actually had the eggs paired which has been hypothesized as indicating it had dual oviducts. They are also long eggs that are oriented vertically that were probably partially buried by the mother and or father dinosaurs. In the nest, that orientation and the duality of those eggs, those are trace fossils. But the eggs are body fossils. See, we could do an entire exam on this! But I won’t.
Jen: I figured you would have an opinion on it.
Jen: I just remembered that from class, like, it’s debated, and heated arguments.
Tony: Oh you could go on and on with it; it’s fun!
Adriane: Really cool stuff. So getting back to Georgia specifically, because you live there, you write a lot about it, what can ichnology tell us about Georgia’s future specifically?
Tony: Yeah, the Georgia coast, I write about this in ‘Tracking the Golden Isles’ in the last couple of chapters. In fact, chapters I talk about sea level change, and how sea level change, and especially storms, we’re going to have an increasing number of storms, we’ve had two hurricanes hit the Georgia coast recently, uh, Matthew and Irma. Those are going to change those environments very quickly, literally overnight. What happens then is that’s new real estate that the trace makers come in, and they start occupying that real estate right away. So for instance, there’s a salt marsh on Sapelo Island that over the past ten years I’ve watched it disappear. And it’s gone. The last time I was down there in, um, February, it was gone. It is now under several sheets of sand. So the salt marsh that had fiddler crabs leaving there little burrows in it, that had mussels attaching to the surface, that had root traces from Smooth Cordgrass, those traces have now been replaced by a layer of sand that has fiddler crabs, sand fiddler crabs, and ghost crabs, and now insects that are burrowing in the top of that. These traces give us a prediction, a prediction of what’s going to happen with climate change on the Georgia coast as sea level goes up, but also storms. That storms are going to go over the pre-existing environments, and we’re getting what we call Walther’s Law happening in real time. We’re actually watching these laterally-adjacent environments go over one another vertically. And we’re seeing this happen over the course of just, in a few years we can watch it. This is where traces give us a prediction. We can say that this environment is going to change into this environment, and these are what animals and plants are going to be moving into that new neighborhood once that change takes place.
Adriane: So, relatedly then, this can probably be extrapolated to other states along the eastern coast of the U.S., right? Because we’re all kind of part of the same, you know, in North Carolina, we have the Outer Banks barrier island systems, um, so what can ichnology tell us about the more global implications of anthropogenic climate change?
Tony: Yeah, this is, this is a really good question because I like to point to the east coast of the United States, and particularly its barrier islands, as being kind of canaries in the coal mine. We have, on the east coast of the United States, going from Florida all the way up to Maine, we have barrier islands that people have modified a lot of them, but then there are a good number that have not been modified so much. The Georgia coast has some of the best examples of that, of barrier islands that have not been modified so much by humans. What we can do is look at those as canaries in the coal mine and think about how as climate change starts impacting those environments, how do traces inform us about those changes all the way up the east coast? Now, globally, globally a lot of geologists, sedimentary geologists, study the barrier islands of the eastern U.S. as examples, that they then apply worldwide. So of course barrier islands vary worldwide, but the east coast ones are often a model for what we see worldwide with coastlines, and how coastlines are changing. Especially because of human interactions with those coastlines. Traces, I think, are another tool that we can put in our toolbox. That we can use traces and ichnology to better understand these changes as we go into this uncertain future with storms, greater storms, fiercer storms, and then sea level rise. What’s going to happen? Traces are yet another tool in our Swiss Army Knife of tools that we use to predict how the, how the present is going to tell us something about the future.
Jen: I think it’s also important to mention, um, we’ve been talking a lot about how we think about like different groups of traces, being in certain areas, um, there’s a lot of, uh, like seminal work that really explained things like oxygen content, the type of substrate, and why you expect to see these different types of traces in these assemblages. So some things do better in high energy, some animals do not like high energy and need something a little bit away from the coastlines to kind of really thrive and establish their burrows. Uh, but maybe, uh, Adriane and I can include some links, and maybe you have some links you could send us so we can include them in a little document for people who are interested in kind of diving more into getting a better understanding of these assemblages. Because they are very valuable.
Tony: I agree completely and I’m really glad you’re going to do that because one of the, um, I think one of the applications to paleontology that we’re seeing today with climate change and thinking about how climate change fits in with paleontology, is this whole field of conservation paleobiology. And both of you have expertise in this, and then we have lots of other paleontologists who are working in this discipline. Now working with biologists and conservation biologists in particular for how can we, how can we use our knowledge of the past to better inform ourselves about what to do in the future. Particularly with conservation biology and preventing extinctions, and those kinds of, those kinds of measures that we need to act now on it. And, we’re here to help. So, great idea! I’m looking forward to helping with that.
Jen: I have sort of a, sort of a question I think uh, our followers would be interested in. So you’re a faculty member, who teaches, does research, and you’re also an author, but there are other jobs for ichnologists if people are interested in studying trace fossils. Do you have any suggestions for them?
Tony: Yeah, traditionally, with ichnology, a lot of the ichnologists have been employed in the, um, well in the energy industry, for lack of a better term. They used to say petroleum but then it became petroleum natural gas and all the fossil fuels. As that is waning, as we are seeing this transition now from a fossil fuel intensive economy, as we’re going into alternative fuels and the future is happening now in that… It’s not necessarily those ichnologists are going to be out of a job. So what I just said is, our working with conservation biologists, I see that as part of the future of more traditionally trained ichnologists. However, I would also like to point out that there’s a whole discipline of conservation biology of people who work with tracks. And they work with tracks, of say, endangered animals, or doing surveys of animals in protected ecosystems. I think this is something where we ichnologists can also contribute to the people who are out there tracking animals, taking data, uh, GIS data, say through CyberTracker, or other GIS mapping. I think this is something where we can contribute to, that we can work together with conservation biologists, and better see, I guess what you would say is the unseen biota, the, the animals you don’t go out and just witness everyday. Traces add an extra dimension, and really expand your, your world view of what lives in a given place. Does that help?
Jen: Yeah that’s an excellent answer!
Tony: It gets…Yeah, and it gives hope for those, those people who love ichnology now, that yes you will get a job somehow! You’re not useless.
Jen: Yeah I was remembering in ichnology class, I don’t think we focused on cores, but I remember Dan brought out some cores, and I was like, oh boy! Like trying to look at the like, just the side and the little squiggles. But, like that is also like, that is a challenging puzzle to try and do if you’re interested in really examining these minutia of bioturbation long ago, in these core segments.
Tony: Here’s what’s really great though about, you’re all trained as geologists, and a lot of ichnologists are trained as geologists, is we really get these basic principles though, like cross-cutting relationships. Once you have that little Steno principle, you can apply it with trace fossils where, with cores you can say ‘this burrow is cutting across this burrow; this burrow is cutting across this one’, and you can work out the sequence. And then you can see where it goes from a soft ground to a firm ground, to a hard ground, you can work out that time sequence relatively speaking. This is where we, being trained as geologists, we really have a, I won’t say an unfair advantage, but I’ll just say, yeah, we’re pretty darn cool! That we, we actually have those skills that we can apply in universal ways.
Adriane: That’s so neat that you mentioned cores, and that came up and you can see these 3D relationships within the core. So I also sail with the International Ocean Discovery Program, and we sailed in 2017 to the Tasman Sea. And when we were coring there, we brought up this core, and they had, I think the sediments were of Oligocene or Eocene age, beautiful Zoophycos in them, and a lot of them were pyritized. And going back to what you talked about, certain traces mean certain things, and I was like ‘Ah, I’ll bet this means it was really deep, you know, deep water, maybe low oxygen, maybe low nutrients if I’m remembering correctly from our ichnology class years ago’. I got really excited over that, and I don’t know if other people did but…
Tony: I’m excited now!
Adriane: I think I have… Hold on, I might have that pyritized zoophycos piece in my desk.
[Tony and Jen gasp with excitement]
Tony: Can it get any more thrilling?!
Jen: It can! So actually Alycia used to do these dances, and I’m pretty sure she has a Zoophycos dance. Am I wrong? I think, I’m pretty sure. I’m pretty sure she would go like this, and, she, like, this is supposed to be like simulating the feeding, and she would turn around in circles.
Tony: Oh, we need to get that.
Jen: And she’d dance in front of her classroom!
Tony: And by Alycia you mean Dr….
Tony: Yeah that’s what I thought; okay. I think we need to get video and we need to post that sometime.
[see video for Alycia’s Zoophycos dance]
Jen: Yeah she has one for lophophores, Zoophycos, and I, I’m sure I’m missing a couple.
Tony: Yeah, yeah. So this is something I do in my classes is I will sometimes imitate trace making behavior. So I’m really glad to hear Dr. Stigall does this too.
Jen: It’s not just you!
Tony: Yeah! It’s not just me.
Adriane: Yeah unfortunately I can’t find that pyritized Zoophycos; this is really mean, oh I wish I had it!
Jen: Well if you find it, get a picture of it and we can pop it in
Adriane: Oh true, yea!
Tony: That’s fair. Yeah. Yeah and what’s really, what’s neat is that you mention the pyrite, and I got really excited about that because pyrite, people who don’t even know paleontology or ichnology they know about prite; it’s fools gold. That really tiny pyrite that they call framboidal pyrite, that is facilitated by, uh, sulfate-reducing bacteria. So there’s a story there! You have these anaerobic bacteria that are facilitating the reaction of iron, and sulfur, causing those to react. And that pyrite then, this is kind of a trace of the bacterial behavior, if you want to call it that, interacting with the organic substrates made by the Zoophycos making animal. And absolutely, yes! It tells you something about what was happening with the oxygen levels on the seafloor. That’s why I got so excited when you said that.
Adriane: Yeah it was really great when we pulled up this core and sliced them open, and they were on the table and I went ‘Oh my God, look at all these Zoophycos!’. It was great fun!
Tony: I’m so glad you shared that.
Adriane: I’m just sorry I wish I had thought about getting that specimen earlier. That’s okay I’ll keep looking for it and I can put a picture in.
Tony: That’s okay.
Jen: I don’t think we had anticipated coming to cores in this conversation, it just happened.
Adriane: It did, it was….
Tony: You never know! It’s kind of like, I don’t know, uh, a meandering trace fossil. Sometimes it just meanders all over the place and you never know where it’s going.
Adriane: Exactly. Well Tony that’s all the questions we had for you, we’ve been going for about an hour. Is there anything else you wanted to talk about that we wanted, that you wanted to cover that we didn’t cover. Jen was there anything else?
Tony: Yeah I guess, I guess as a, just an inspirational message for everybody is that traces are everywhere. Traces are everywhere, and even in quarantine conditions, you can go out and you can find traces. So this morning I went out for a little walk, I’m in my neighborhood here in Decatur, Georgia, next to Atlanta, just walking through my neighborhood and my, I took pictures of, um, dog tracks in cement, cat tracks in cement. I even found what I’m pretty sure are mourning dove tracks that were left in cement. That, I was doing field work this morning, and it felt like paleontology, it felt like ichnology. But if you want modern traces, you can go to your local park, look at ant nests, look at some of the bee nests, that were, um, just a month ago were bee nest, ground nesting bees that were in the park next door. Traces are everywhere! Once you start looking, you’ll find them. So, if you’re, if you’re quarantining and you’re just like ‘uh, I’m so bored!’, go out, you’ll find some traces, you’ll get excited! They’re everywhere, just look for them.
Jen: And it would be cool, oh sorry. I was going to say, it would be cool to think about every trace fossil like my cats could make. Do they make similar trace fossils or different trace fossils, and what behaviors are represented with like the suite of what remains.
Tony: Yeah, yeah. I’ve thought about doing a book like ‘The Ichnology of Cats’; it would have a catchier title! But we have two cats here and oh man, uh, yeah that’s, that’s a book that would write itself pretty quickly.
Adriane: Yes. Well I have a question, thinking about modern traces, I had this weird question. Are mosquito or bug bites on us, are those traces?
Tony: Oooohhh, yeah. So, yeah, here’s the thing: if you have a wound, okay so a wound, it is a trace temporarily of that mosquito’s behavior, or parasitic dipterans in general. So it’s a trace of its behavior however temporary. But then, if it heals, you don’t see it, well, then, then it’s not preserving it. Now if you had some sort of scar, like if you had a good, a good bite from something, or a pinch from one of those, I don’t know, shell crushing crabs, I wouldn’t want that. If it left an actual scar, then that’s a trace that lasts. So then it, it really does depend on, is the substrate conducive to preserving that trace. In my book ‘Dinosaurs Without Bones’ I actually talk about, there’s a wound that was in dinosaur skin. I think it was a, a Hadrosaur that actually had a wound preserved in that fossil skin. So that’s a trace fossil of whatever inflicted that. Now, the authors thought maybe it was a tooth trace, but I also allow for the possibility that it stumbled into a thorny plant. In which case, that would be a trace of the Hadrosaur being really derpy and clumsy and ‘whoops!’ stumbling into a plant. That’s not a trace of the plant. So good question, and yet another question that I can ask my students to torture them; thank you.
Adriane: Yeah, of course, yeah. Speaking of scars and cats, I’ve got some scars on my arm from where my cats have bitten and scratched me over the years, so that’s cool now that I can say those are Felis catus tooth traces.
Tony: That’s right. See if they make it into the fossil record.
Adriane: Yeah I doubt it, but we’ll see!
Jen: There are cool fossils of echinoderms, they actually heal. So if something, like, bites them or like nibbles on something, sometimes you can find, find the like trace of that in their skeleton. It’s like, it was clear that it wasn’t a postmortem, because you actually see them trying to patch their body back together. Which is so cool!
Tony: Absolutely, yeah, and there are bite traces, I’ve seen them in modern sand dollars on the Georgia coast, that yes, it heals, then you see fossil examples that are healed bite traces in, uh, trilobites too. Um, yea, this is actually, yeah I can’t reveal it, but the next book I’m going to do is getting more into hard substrates and those kind of really cool traces too.
Tony: Yeah! So that’s neat. Thanks for mentioning echinoderms, which are among the coolest animals ever, right?
Jen: I had to!
Tony: Well, yeah! Okay, anything else?
Adriane: I…. I could probably keep going and talk all day, but….
Tony: Yeah, this is, this is such fun!
Adriane: I know, yeah, I really enjoyed talking trace fossils. I haven’t really thought about them so critically in so long, so this has been a really fun, dredging back up what we learned in ichnology.
Jen: Yeah, we’ll have to send that to Dan! The video, when it’s done, see what he thinks of it.
Tony: That’d be great! Yeah, I would love his input on it. And we’ve got to get that dance on tape.
Jen: Oh Alycia’s? Yeah! I’ll ask her about it. Maybe we can get Dan to do it?
Tony: Even better!
Jen: Doubt it!
Adriane: That’s so great. Well thank you Dr. Martin for coming and talking to us today about trace fossils and ichnology and what they can tell us about the past and the future. We greatly appreciate it! Um, and we hope everyone goes out and looks for traces, modern day, on yourself if you even feel the need to, through scars or bug bites, and around ponds and nests, um, so thank you so much for joining us today, we greatly appreciate it!
Tony: You’re very welcome! Thank you for asking me to be on Time Scavengers; it’s been a pleasure!
Jen: Thank you everyone for sticking with us to the end of our first interview. This was certainly an interesting learning process. So we had a really great time chatting with Tony. If you have any questions for Tony, Adriane, or myself, please leave them in the comments below and we’ll do our best to address them. We look forward to sharing more areas and facets of paleontology with you through these interviews.