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Meet the Museum: The University of Nebraska State Museum

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Sarah here–

Not too long ago, I took a trip to Lincoln, Nebraska (USA) at the kind invitation of the Earth and Atmospheric Sciences Department. While I was there, I was able to take some time to go on a tour of the University of Nebraska State Museum, a place I’ve worked with for a long time but never had a chance to see in person! Today, I’m going to introduce you to what isn’t on display- as with the majority of museums, only a tiny percentage of their collections are on display for the public- the vast majority of specimens are stored behind closed doors for preservation and research. One thing to note- if you are ever behind the scenes at a museum, you should check to make sure photographs are OK. Some of the specimens may not be published yet and scientists are not ready for images to be public. In this case, I made sure to ask for permission before I took the photos and asked for permission to share them with interested readers, which they were kind enough to allow!  

The paleontology holdings of Nebraska and surrounding states in the Midwest are, without question, spectacular. Within the halls of this museum lie the remains of camels, elephants, rhinos, and mammoths that lived long ago in North America (Fig. 1). This museum also has fossils from even longer ago from a time when the Midwest was completely underwater as a shallow sea. I first started my tour in the main display halls of the museum, where I got to see skeleton reconstructions of the diversity of fossil proboscideans (the group containing mammoths and elephants; proboscidean literally means ‘elephant’s trunk in Latin) that lived in and around Nebraska a few million years ago. 

a museum display containing a variety of skeletons- all probosdiceans. Some are quite large, some are small, like the size of deer.
Fig. 1. A diversity of animals related to the modern elephant used to be present in North America and in this case, specifically those in the Midwest. They varied greatly in size, shape of their tusks, and more.

Next, I visited the invertebrate collections, which hold special meaning to me. I worked with this very museum to perform my first scientific research project, which became my master’s thesis. I took the time to visit the specimens that I studied- crinoids belonging to the genus Erisocrinus and closely related taxa that came from Oklahoma, USA (Fig. 2). I saw some very interesting crinoid fossils that preserved features of parasitism as well (Fig. 3)

A drawer of crinoid fossils- most are the round cups with the arms disarticulated. Hundreds of specimens in boxes with labels, none of them readable from the image.
Fig. 2. A drawer filled with crinoid fossils from the Midwest of the United States. I studied some of these very fossils for my master’s thesis
A box of crinoid stems (maybe 2 inches length max, but most are .5 inches or so in length). Most of them have substantial holes drilled into them- some have nearly a dozen!
Fig. 3. Crinoid stems with parasitic traces left on their bodies- you can see how the stem gets distorted and bloated with the more parasitic pits that are left on the body! My finger is in the bottom of the image for scale.

I then went to the vertebrate collections area, which was just incredible. Many of their fossils come from the Ashfall Fossil Beds from the northeast area of Nebraska. Just about 12 million years ago, an active volcano spewed significant amounts of ash- this type of volcanic ash contained tiny natural glass shards and, as you can imagine, it’s quite harmful to breathe it in. Unfortunately for the animals that were alive at the time, they did breathe it in, and they died- the ash continued to fall, and this led to some exceptional preservation of their skeletons, many of which have been uncovered (Fig. 4) and more are likely to be found in the future. 

A map of the skeletons found in the site. They are color coded to indicate which animals were found, listed here in the figure caption. The vast majority were rhinos in this area, but there are a number of horses too, with the deer and camels less common. Many of the rhinos are grouped very close together.
Fig. 4. This is a map of the skeletons uncovered in the Ashfall Fossil Beds, of the skeletons of rhinos, horses, camels, deer, and footprints. Image credit: University of Nebraska State Museum

Ash has the potential to preserve fossils extremely well and this fossil area is no exception at all. The collections of the University of Nebraska State Museum are filled with rows upon rows of beautifully preserved skulls and other bones of vertebrates that fell victim to the ash (Fig. 5, 6, 7). 

Shelves of rhino jaws- dozens of them. Most are just the bottom half, but the teeth are in place and detailed. Many are juveniles but the majority are adults.
Fig. 5. A row of rhinoceros jaws of all sizes, all exquisitely preserved.
A close up of a juvenile jaw bone of a rhino- the scientists who found it nicknamed it "Charlie" as the label indicates. the back most teeth of this one look missing, but the ones closer to the center are well preserved. lower jaw bones only.
Fig. 6. This is a close-up image of one of the juvenile jaw bones of a rhino fossil- many of the specimens were given nicknames, and this one is named “Charlie”.
A bird fossil- gray in color.the delicate bones are highly detailed in place as they would have been in life for the most part. you can see tendons along the bones of the limbs of the bird. Incredibly well preserved.
Fig. 7. This is a bird fossil that was found in association with the ashfall. This detailed preservation is not common for birds, whose delicate, hollow bones are often not well-preserved- but in this specimen, if you look carefully, you can even see where the tendons were.

This museum was a really great place to visit! If you ever find yourself in Lincoln, Nebraska, I highly encourage you to check out the museum! You won’t be disappointed. If you’re interested in learning more about the Ashfall Fossil Beds, read the linked website! 

Geology of Oregon Series: Part I: Hot Springs

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Sarah here –

In 2022, I took a road trip around Oregon on the west coast of USA to see all the incredible geology there is to see there. Oregon is an incredible natural geologic laboratory because there are so many different processes at play across different environments: you can see hydrology in action through massive waterfalls, naturally heated bodies of water from geothermal energy, the movement of sands in desert environments, and more- all in a single state! I’ll be writing a series of articles on the geology that I saw, so that I can share with you a small part of the incredible beauty that this Earth has to offer. 

My journey started near Eugene, Oregon, a few hours inland from the Pacific coast, with a friend of mine from college. Our first stop was to go swimming at the Terwilliger hot springs in the Willamette National Forest. A hot spring is a naturally occurring feature caused by geothermal (geo meaning Earth, thermal meaning heat) activity- Earth processes cause the water in a spring to be far warmer than we would expect a typical body of water on the surface of Earth! This geologic phenomenon does not occur everywhere on Earth by any means. 

So where does this geothermal activity come from and why is it restricted to certain locations? It comes from areas with volcanoes, both active and dormant (like Iceland, Hawaii, and Oregon!). The magma (lava that’s still underground) of the volcanic system is in contact with rocks closer to the surface of Earth- that heat is passed to water that is in contact with the rock (Fig. 1).

A diagram of how water is affected by volcanic activity. Starting from the bottom: a layer of magma in chamber is in contact with porous rock above it- heat is rising. There is water in that porous rock that is heated from the magma. The water can rise to the surface and form a few different things. It can stay in the ground as steam, it can come out as a hot spring, or it can erupt as a geyser. The top of the diagram shows a hot spring as a small pool with steam rising and a geyser with a large fountain of hot water bursting from the Earth. The water will eventually return to the ground and begin that cycle again.
Figure 1. A diagram of how magma below the surface affects the temperature of ground water- as the magma chamber heats the porous rock above it, water that is in that rock is also heated and rises to the surface- in this case, it is a hot spring, but the water can also come to the surface in different ways, like geysers!

The temperature of the water can vary from pleasantly warm to extremely hot- meaning, some areas are safe to swim, and others are not (so if you’re in an area where hot springs exist, always check local safety guidelines!). Typically, areas with active volcanism (meaning, they’ve erupted in recent history, as opposed to dormant, where they have not erupted for some time, but have the possibility to erupt in the future) will have higher temperatures associated with their hot springs. At Terwilliger (Fig. 2), the water ranges from 112˙F to about 85˙F, so it felt a lot like a hot tub! The hottest water is closest to where the water begins to flow- so, the water closest to the heat source- as it travels downstream, it cools. 

The view of the hot springs from the most uphill portion- it's in a forest, surrounded by trees and faint views of mountains in the background. there is a wooden platform off to the side. Directly in front is a pool of water about 8 feet across and a few feet deep (maybe 3)- the rocks make a circle around this pool, and water overflows over some of the rocks to continue to trickle downstream to pools outside the view of this image
Figure 2. The hot springs, from an upstream view. The pool directly in view is the warmest- as the water in it travels downstream, it cools a bit.

Due to the nature of hot springs, the water there often contains a high amount of dissolved minerals, and the minerals present in them can range drastically, as can the pH of the water. Often, you’ll find that the water can appear very different in color and clarity across different hot springs, and that’s why- the dissolved minerals. In Teriwilliger, the water has a lot of sodium, calcium, magnesium, iron, aluminum, silica, and sulfates present in it. 

Despite the high temperatures of the water, life still thrives in this environment, too- while this hot spring is not among the warmest, it is still a difficult environment for many different organisms to survive in. However, certain species of blue-green algae, or cyanobacteria, have adapted to be able to thrive in these extreme freshwater environments (species that can live in extreme environments are called extremophiles), where most other species cannot. These cyanobacteria can be seen on the rocks closer to the edges of the pool (Fig. 3) and it can be very slippery if you step on it- so be careful! I wanted to highlight these cyanobacteria because cyanobacteria represent some of the earliest complex life on Earth, with their fossil record extending billions of years- we can thank them for providing a lot of the oxygen we breathe today! Biology and geology are intertwined with one another, so by studying both, we can get a fuller picture of the world around us.

A close up of the hot springs pool. The water is a distinct greenish shade and on the edges, you can see a blue-green shade to the rocks that is actually the algae. it stands out because the other rocks, not coated in algae, are mostly basalt, so they are dark gray in color (lighter gray if they have been weathered more)
Figure 3. A close-up image of one of the pools at the hot springs- note the distinct color of the water and the blue-green algae (cyanobacteria) that coats the rocks. It’s tough to see the cyanobacteria in the deeper water, but toward the edges, you can see a colorful sheen- that’s the blue-green algae! A limited number of organisms on Earth thrive in extremely warm waters, but those that have adapted to these extreme environments can really thrive there!

Rinu Fathima, Ph.D. Student in Marine Science

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Image 1: Working on foraminifera means spending long hours sitting on microscope, basically microscope is your best friend.

Hey, I am Rinu Fathima, a second year Ph.D. student from National Institute of Oceanography, India. I am originally from Kerala, a beautiful coastal state in India and currently lives at Goa which is also along the coast. Lucky me. I am a dreamer, thinker, crazy about movies and love spending time reading novels or watching sunsets. 

My research focuses on understanding past monsoon patterns using microfossils preserved in the ocean. Among the different microfossils that are present in the ocean I specifically make use of single celled, very beautiful, and extremely diverse organisms called foraminifera. Despite being so small the amount of information these organisms can share is huge. Both their shell morphology and composition tell a lot about the environmental conditions in which they lived. This aspect is used to understand past climate. I am particularly interested in a climatic event called mid-Pleistocene transition event that occurred between 1200 to 750 ka. Before this transition Earth’s glacial cycles followed obliquity dominated cyclicity and after this they changed to eccentricity dominated cycles. What caused this change in periodicity of glacial cycles is still a debated topic in the scientific community. I am very much excited about what results my research beholds about this mystery time interval.  

Examples of microfossils. They are light colored foraminifera with multiple chambers. The two on the left are one species and the right most two are a different species.
Image 2: Even though these pictures look similar they are different species of planktic foraminifera. Identifying and characterising their eccology forms an important part of my research.

I cannot really recall myself wanting to be a scientist from a very young age. I was good in school which made me believe I should pursue science. Later, I enrolled for Bachelors in Geology. Even then, I was not very much aware of what I was stepping into. But things took a quick turn later. The field visits during the course, practical classes, workshops everything excited me. The best thing was getting to travel all around the country as a part of the field work. The science suddenly felt personal. Later I joined for my masters in Pondicherry University. This was a beautiful ocean facing campus, where I learnt the different research potential of geology and an interest in oceanography. When COVID struck I was preparing for exams to get into Ph.D. during which I read a lot of books on Oceanography. By the time I qualified my exam I was a hundred percent sure on the topic in which I wanted to do my research. Yes, you guessed it right, Oceanography. 

Three images in a row showcasing vacationing and working in on the Sagar Kanya a research vessel. The first image (farthest to the left) is a sunset photo with Rinu in the foreground. The middle image is a research instrument against a dark background. The third is Rinu holding the side of the ship and a stack of books.
Image 3: Vacaying and working; This is me last year onboard Sagar Kanya for collecting samples across North-eastern Arabian Sea.

I feel connected to my research because I think I can make an impact. Coming from an agrarian country that depends heavily on monsoon, I believe understanding monsoon is very important. To have better predictions and climate models the past studies with well-defined forcing/response and boundary condition information is very crucial. 

I always felt that I should have joined the field and identified my passion a bit earlier, but I am really grateful that I found it even if a bit late. Right now, I feel like getting paid for doing something I love. My advice to anyone working in science will be to enjoy the process, that’s what I have been told by my supervisor and I have never been happier. 

Foreground has three individuals in matching shirts behind a table. On the table is a microscope and other equipment for others to use. The purpose is to share their love of microfossils with others.
Image 4: Assisting students in the important of microfossils on international fossil day.

Josh Abbatiello, Ph.D. Candidate

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Tell us a little bit about yourself. Hello, my name is Josh Abbatiello. I have a Bachelor’s of Science in geology and am currently a PhD. Candidate (geology as well) at the University of South Florida. I’m a huge fan of movies, – my favorite genre is horror (I don’t think I can pick a favorite, so be prepared for a long conversation if asked). I also love watching T.V. and anime. If I had to pick, Breaking Bad may be my favorite T.V. show and I can’t possibly pick a favorite anime. I’m an avid Sci-Fi and fantasy reader. Isaac Asimov is my all-time favorite author, and I am on a constant mission to collect all of his physical books. I’ve been a cat person my whole life and currently have two cats: a tortoiseshell named Reina and a black cat named Nefertiti. Since middle school, I’ve played trombone. I performed in the marching band throughout high school and college. I don’t play as much as I would like to. Being a band nerd has heavily influenced my music tastes. I love to listen to literally any kind of music. Due to having attention deficit hyperactivity disorder (ADHD), when listening to music, I tend to analyze different facets of the music (e.g., why people like it, time signature, and meaning of the lyrics). I have the tendency to do this with all forms of media. Thank you for reading and getting to know a little about me.

White man with shoulder length brown hair wearing a purple shirt smiling at camera in front of nature preserve on a sunny day.

What kind of scientist are you and what do you do? In the broadest sense, I’m a biogeochemist. I use techniques of biology, geology, and chemistry to understand the element phosphorus. I study how phosphorus pertains to the origin of the earliest molecules billions of years ago and its immense importance to us today. I also relate that information to determining potential for life on other planets.

What is your favorite part about being a scientist, and how did you get interested in science? My favorite thing about being a scientist is getting to think about questions that we don’t know and working towards solving them as a scientific community. My path to getting interested in science came from a young age. My stepdad would rent the Carl Sagan (a famous astrobiologist who pioneered the field of exobiology) version of Cosmos on VHS from the library, and I became enamored with space. His ability to teach and connect to a wide audience in a way that inspired many including myself. I believe it’s important to be able to communicate with and inspire the next generations.

How does your work contribute to the betterment of society in general? I believe that working towards unanswered questions such as the origin of life betters society. This research provides a framework for possible environments of life on other planets, while providing a better understanding of how humans came to exist on Earth. I’m a part of the Scientist in every Florida school (SEFS) and Skype- a- Scientist programs where they give scientists the chance to reach students and hopefully inspire them to pursue a career in Science, Technology, Engineering, Arts, and Math (S.T.E.A.M). One of my goals is to encourage students with learning disabilities (like myself) that they can do anything neurotypical people can. Growing up, my mom didn’t really believe in diagnosing issues. As such, looking back after my adult diagnosis, I had all the hallmark signs of ADHD and unfortunately constantly heard “If you tried harder or applied yourself” comments from teachers and even siblings. These comments would send me into a spiral of depression and anxiety. Even so, with mental health treatment and gaining a support system in my adult life, I was able to work through my depression and anxiety. I’m soon going to be graduating with my PhD.

What advice do you have for up and coming scientists? As cliché as it sounds, you can do it. Persevere and don’t give up. The world of science is huge, and you can mix and match disciplines to match your interests, like how I have mixed biology, geology, and chemistry. Stay inquisitive and never stop learning. It’s never too late or early to pursue what you’re passionate about.

Hosting the 2023 Natural History Education DemoCamp

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Jen here – 

I am a member of the Society for the Preservation of Natural History Collections (SPNHC) Education Committee. One of our primary annual activities is to host a virtual Natural History Education (NHE) DemoCamp. This year was our third iteration of the DemoCamp. The goal of the NHE DemoCamp is to share, discover, and discuss educational materials that have a framework in natural history. This is building upon our previous iterations of the ‘education share fair’ that were hosted at the in person SPNHC annual meetings from 2018–2019.

Educational materials that were shared by presenters varied widely in scope, audience, format, and topic from how to engage audiences with virtual natural history collections resources to how to build engaging in-person public programming. You can find short descriptions and links to each educational resource on the event’s abstract volume. You can also find recordings for all of the demo sessions on the DemoCamp website — these will soon also be available on the SPNHC YouTube Channel. This year’s NHE DemoCamp had over 150 registrants with 14 different live demonstrations and discussions that took place over the two days. 

Banner with a series of logos for organizations that partnered with the education committee to host the event
Banner with logos of the various organizations that assisted in recruiting presenters and participants for the 2023 Natural History Education DemoCamp

We are encouraging all of our presenters to share their resources as Open Education Resources (OER) on the SPNHC Natural History Education Portal. This portal is also open to anyone! We welcome anyone to add their education or outreach materials to this community space. It only takes a short amount of time to create an OER and it will increase your resource visibility. The portal is hosted on QUBESHub, which also gives your resource a DOI and allows others to duplicate your content and make modifications while linking back to the original resource. It also tracks metrics that are easily reportable. If you’re interested but aren’t sure how to get started, contact our committee at our gmail account: educationdemocamp @ gmail.com

A huge thank you to all of the organizers from the SPNHC Education Committee and to all of our partners that helped us spread the word! Stay tuned for announcements for next year’s NHE DemoCamp! We are also always looking for new partnerships and members. Please fill out our interest form for more information, or reach out to us through email!

Newly discovered fossil frogs shed light on the Amazonian environment 10 million years ago

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Fossil Frogs from The Upper Miocene of Southwestern Brazilian Amazonia (Solimões Formation, Acre Basin)

Fellipe P. Muniz, Marcos César Bissaro-Júnior, Edson Guilherme, Jonas P. De Souza-Filho, Francisco R. Negri, and Annie S. Hsiou

Summarized by Ryan Taylor. Ryan lives in Clearwater, Florida, and is a student at the University of South Florida (USF) who is currently seeking a B.Sc. in geology. He also works as an assistant engineer for a civil engineering company in Tampa, Florida. One of Ryan’s favorite activities is going garage sale hunting every Saturday morning.

What was the goal of the paper? This study used newly discovered frog fossils, from the genus Pipa and Rhinella, from the southern Amazon to gain a greater understanding of what the biodiversity and the environment of the southern Amazon was like in the Late Miocene (6 to 11 million years ago). Scientists accomplished this by comparing the differences in the structure of the newly discovered Pipa and Rhinella to modern-day frogs of the same genus (a taxonomic rank above species).

What data were used?  Scientists used the bones of the frogs that were found at the Talismã site in the southern Amazonas of Brazil. These bones included the frogs’ ilium and ischium (hip bones), humeri (front legs), and other parts of the frogs’ skeletal structure. This fossil data was compared with data collected from previous studies for small, fossilized animals found in the same region. The researchers also collected samples of the bones of frogs that live in that area today to compare the differences in the structure against the fossil frogs that were found.

Methods:  The researchers recovered multiple samples of frog bones that were in the southern Amazonas region of Brazil by examining an exposed section of sediment layers (Fig. 1). Next, they identified differences in the bone structures of the fossil frogs as compared with the same species of living frogs that are found in the same area today. Using this data of the differences in bone structures, researchers performed an evolutionary tree analysis of the frogs they found to how they were related to other frogs alive today. This tree allows the researchers to see how the frog diversity changed over time to what we have today. They compared the bone structures of the newly found fossils to frogs known to be living there in the late Miocene supporting that the new frog fossils used to live there at that time too.

This figure shows a map of Brazil and focuses on a part of Brazil in the southwestern Amazon with the location of the fossil excavation and some of the rivers that are in the area. There is also a representation of a 5.3-meter-tall cross-section that was in the ground. This cross-section showed the clay/mud layers and the different types of fossils found in them. Reptiles were found between 1.12 and 0.68 meters deep. Fish, anurans (frogs), mammals, reptiles, and crustaceans (crabs) were found between 2.15 and 2.34 meters deep. More crustaceans were found between 2.34 and 4.89 meters deep.
Figure 1 shows the area where the samples of the new frog species were found. The layer in which the bones were found is helpful in finding the approximate age of the frog bones because each layer down from the top represents an older time in geologic history. The anurans (frogs) were found between 2.15 and 2.34 meters deep. Other animals that were found include: crustaceans, fish, mammals, and reptiles which all lived in the same time period the frogs lived.

Results: The researchers found two frog taxa here belonging to the genera Pipa and Rhinella. The results of this study showed that a diversity of frogs in genus Pipa lived in the southern Amazonas region. The Pipa fossils that were found are some of the oldest for the genus which supports a previous study that was done in Venezuela, showing Pipa also lived there in the late Miocene. The discovery of Pipa in the southern Amazonas gives an idea as to what type of environment this region had. Pipa is only known to live in aquatic environments near stagnate waters like lakes and swamps, showing that this is likely the type of environment that existed here in the late Miocene. Frogs in the genus Rhinella are not very dependent on aquatic environments and can live in a broader variety of habitats, but their tadpoles are dependent on a nearby water body. This study also found a possible new species of frog belonging to the genus Rhinella that also lived in the area. There are differences in the pelvis of the fossil Rhinella compared to today’s frogs, indicating that they are different species.

Why is this study important? This study is important because it showed what type of environment the southern Amazonas had in the late Miocene. They were able to see that the Amazonia used to have more lakes and was possibly less tropical, as compared to its modern-day rainforest environment. This study also added clarity to the evolutionary history of when these types of frogs may have evolved.

Broader Implications beyond this study: Any land species, like frogs, are not commonly preserved in the fossil record.  When these rarer fossils are found, they offer massive contributions to the scientific community.  

Citation: Muniz, F. P., Bissaro-Júnior, M. C., Guilherme, E., Souza-Filho, J. P., Negri, F. R., & Hsiou, A. S. (2022). Fossil Frogs from the Upper Miocene of southwestern Brazilian Amazonia (Solimões Formation, acre basin). Journal of Vertebrate Paleontology, 41(6). https://doi.org/10.1080/02724634.2021.2089853

Finding traces of food and guts in 588 million years old Ediacaran-type critters

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Guts, gut contents, and feeding strategies of Ediacaran animals.

Summarized by Nilmani Perera, a graduate student in the PhD program at the Geological Sciences program at the University of South Florida. She’s studying evolutionary patterns of Paleozoic (542–251 million years ago) echinoderms with Dr. Sarah Sheffield. She’s also interested in looking into their paleoecology and how it could have played a role in their diversification during this time. 

What was the hypothesis being tested (if no hypothesis, what was the question or point of the paper)?  This study focuses on understanding how Ediacaran animals fed, using three 558-million-year-old fossils from the White Sea area in Russia.

What data were used? Three different fossilized animals were used in this study; Kimberella, Calyptrina and Dickinsonia; Figure1). Rocks containing fossils and surrounding sediment from White Sea area in Russia were analyzed for the presence of fat molecules (lipid biomarkers) that came from their diet.

Methods: Fossils  and sediment collected in the field were prepared and then analyzed using Gas chromatography–mass spectrometry (GC-MS). This is a method used to separate components in a mixture at very fine level, basically at the molecular level. Fat particles in the samples were separated based on their differences in chemistry. Researchers looked for the presence of specific combination of lipid molecules in these samples, which can indicate the origin of the molecules. Comparing the ratios of the different types of molecules allowed them to figure out whether the signal came from the actual organisms or from the surrounding rock. This also allowed researchers to determine if the organism had a digestive tract (also referred to as gut) inside its body

Results: There were several significant findings that came out of this study. First, researchers discovered that the lipid breakdown process in Kimberella and Calyptrina is the same as in modern invertebrates, such as mollusks (like clams) and worms. Secondly, they were able to point out that Kimberella grazed on microbial mats and Calyptrina fed on particles in the sea water or in the marine sediment, like modern day tube worms would do. Thirdly, it was shown that both these organisms had a gut in which their food was digested. Interestingly, none of the specimens of Dickinsonia studied indicated that they possessed a gut, so they either took in food particles by osmosis (where particles move across a membrane) or could have possessed an external digestive system in which they secreted enzymes into the environment to breakdown food and then absorb it through their body. 

The figure contains three Ediacaran animals preserved in rock as fossilized impressions. A. The first figure is of Kimberella, preserved in a light gray color rock and is roughly half an inch long. It is pear-shaped, flat and has a couple of layers to it. B. The second figure is of Dickinsonia, preserved in a light brown color rock. It is leaf-like with ridges radiating from a central axis and about 3.5 inches along its length. C. The third figure is of Calyptrina, preserved on the surface of a beige color rock. It is flat, long, and worm-like with some dark color patches along its length.
Figure 1; Ediacaran fossils used in this study. A. Kimberella, B. Dickinsonia, C, Calyptrina (Scale bar used in Figures A, 5mm; B, 10mm and C, 5mm)

Why is this study important? The findings of this study are important because there’s a lot of research going on to understand how earliest animals evolved and how similar they were to animals we see today. Ediacaran- age animals represent an important turning point in the study of how animal bodies came about and how similar they are to major animal groups we see today. In this study, the lipid molecules preserved with the fossils  allowed researchers to compare them to modern animals with similar life modes. 

Broader Implications beyond this study: This method of biomarker identification can be applied to learn more about the trophic structure in ecosystems that are hundreds of millions of years old. The beauty of it is that this method can be used even when the gut is not preserved, because the method is only using the lipid molecules derived from the diet. 

Citation: Bobrovskiy, I., Nagovitsyn, A., Hope, J.M., Luzhnaya, E., & Brocks,J.J.,  (2022). Guts, gut contents, and feeding strategies of Ediacaran animals. Current Biology, 32, 5382–5389. https://doi.org/10.1016/j.cub.2022.10.051

Using Shark Teeth to Compare Past and Present Shark Populations Along the Southern Coast of Brazil

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Quaternary fossil shark (Neoselachii: Galeomorphii and Squalomorphii) diversity from southern Brazil

Sheron Medeiros, Maria Cristina Oddone, Heitor Francischini, Débora Diniz, Paula Dentzien-Dias

Summarized by Max Raynor, a 4th year undergraduate student pursuing a bachelor’s degree in geology from the University of South Florida. Max currently works for a surveying company in Tampa, where he focuses on making digital maps of the Earth’s surface and ocean floor.  When he isn’t studying geology or working, he enjoys fishing, collecting and curating vintage clothing, and playing tennis.

What was the hypothesis being tested? Scientists used fossil shark teeth to quantify differences between shark populations throughout the Quaternary Period (the past 2.58 million years of Earth’s history). The shark teeth used for this study were collected along the beaches of the Rio Grande do Sul Coastal Plain (RSCP), which extends along Brazil’s southernmost shorelines. Scientists compared and contrasted structural differences between shark teeth to test hypotheses on changing climate conditions throughout the Quaternary and how changes over time affected shark populations along the Rio Grande do Sul. 

What data were used? The data collected in this study included 3,611 shark teeth that had been found on the beaches of the RSCP since 1996. Using the simple technique of manually collecting shark teeth from the beach, researchers were able to find a variety of species to use for this study.

Methods: Participating in a well-documented data collection process known as “beachcombing”, researchers scanned the exposed beach area and picked out shark teeth by hand. The gravelly nature of beach grains, as well as the less-than-perfect condition of many of the teeth found, made it increasingly difficult to find desirable samples over time. The collected teeth were subsequently sent to a laboratory where they were sorted and classified by species. A classified tooth would be analyzed from two different views: where a tooth was adjacent to the tongue (lingual), and where a tooth was adjacent to the inside of the mouth (labial). The characteristics of a tooth from these angles provide the information necessary to correctly identify the corresponding shark species.

Results: By observing the characteristics of the teeth sampled, scientists identified 3,611 teeth belonging to13 different species of shark in the dataset (Fig. 1). While about ¾ of the data were able to be identified to the species, some were only able to be identified to the genus, and some teeth were rendered unidentifiable due to physical alterations and erosion over time. The order Lamniformes represented just 3 of the 13 taxa identified, but was responsible for 2,390 teeth sampled, or 66.18% of the dataset. Carcharius taurus, commonly known as the sand tiger shark and belonging to Lamniformes, was the most abundant species overall with 2,027 identified teeth. With respect to species diversity, the majority of the diversity belonged to the shark order Carcharhiniformes, which represented 8 of the 13 species identified. Carcharhinus leucas, also known as the bull shark, was the most abundant species of the Carcharhiniformes with 191 teeth sampled. 11of the 13 species identified are still found in the region, indicating that the shark community and climate conditions of the RSCP throughout the Quaternary have been fairly similar over the past 2.58 million years.

Figure A: Pie chart of shark orders sampled, from highest to lowest percentage of teeth found per order: Lamniformes (2,390 teeth), Carcharhiniformes (821 teeth), Hexanchiformes (10 teeth), Squatiniformes (2 teeth), and 388 teeth that were unable to be identified to the species.Figure B: Pie chart of the number of teeth sampled from each species, from most teeth found per species to least: Carcharius taurus (2,027 teeth), Carcharadon carcharias (283 teeth), Carcharhinus leucas (193 teeth), Carcharhinus brachyurus (90 teeth), Isurus oxyrinchus (80 teeth), Sphyma (51 teeth), Carcharhinus longimanus (21 teeth), Galeocerdo cuvier (18 teeth), Notorynchus cepedianus (10 teeth), Galeorhinus galeus (3 teeth), Squatina (2 teeth), and Rhizoprionodon (1 tooth). There were 444 Carcharhinus teeth that could not be identified to a species, as well as 388 unidentified teeth.
Pie charts depicting (A) The orders of shark represented by teeth collected in this study and the number of samples belonging to each (B) The species of shark represented by the amount of teeth identified per species in this study.

Why is this study important: The diversity of shark species along the RSCP is important to note because it supports hypotheses posed in other studies that climate conditions have changed little throughout the Quaternary in this region. The two species found in the study that are not current residents of the RSCP, Carcharodon carcharias (Great White Shark) and Carcharhinus longimanus (Oceanic Whitetip Shark) are noteworthy, because they live in open oceanic environments today and are rarely found in the coastal RSCP, The presence of oceanic sharks such as these indicate higher sea levels along the RSCP at times throughout the Quaternary Period compared to present day. Periods of cooler and warmer weather were drivers of changes in sea level and climate changes throughout the Quaternary, resulting in periodic occurrences of shark species that migrated from both warmer and colder waters.

Broader Implications Findings from this study will allow paleontologists and biologists alike to assess how coastal and oceanic shark populations respond to a changing climate and marine ecosystem. Further research on this using different methods than beachcombing could potentially identify different results, as beachcombing can sometimes favor the collection of larger teeth, as it ismore obvious it is to the eye of the collector. Bulk collecting, collecting sediment and sorting it in the lab, may capture different results, but this will require future research. 

Citation: Medeiros, S., Oddone, M. C., Francischini, H., Diniz, D., & Dentzien-Dias, P. (2023). Quaternary fossil shark (Neoselachii: Galeomorphii and Squalomorphii) diversity from Southern Brazil. Journal of South American Earth Sciences, 122, 104176. https://doi.org/10.1016/j.jsames.2022.104176 

Cambrian and Ordovician Trilobite Injuries

jenebauerLeave a comment

New records of injured Cambrian and Ordovician trilobites

Summarized by Matthew Gaborik, an undergraduate student studying geology at the University of South Florida. He will be graduating with the class of 2023. After his undergraduate program, he plans to gain some experience and return to school for a Master’s program. When he’s not studying geology, he likes to play mechanic, kayak, and hike.

What was the point of the paper? The point of the paper was to present new findings on select abnormal (injured or malformed) trilobite fossils in order to expand the record of abnormal trilobite fossils and obtain a clearer understanding of trilobite predation.

Data used: Seven abnormal trilobite fossils, originally housed in the Australian Museum, the Utah Field House of Natural History State Park Museum (U.S.), and the Museums of Western Colorado (U.S.), were gathered for this study because they portray damage to the exoskeleton. These abnormal trilobite fossils were: Lyriaspis sigillum, from the Beetle Creek Formation in Australia, Zacanthoides, from the Half Moon Mine, which is part of the Chisholm Formation in Nevada (U.S.), Asaphiscus wheeleri (two specimens) and Elrathia kingii (two specimens), both of which are from the Wheeler Formation in Utah (U.S.), and Ogyogiocarella debuchii from a quarry in Wales. All formations from which these fossils were sourced are aged to around the middle Cambrian (~510 million years ago), except for O. debuchii, which is from the Middle Ordovician (~450 million years ago). 

Method: Fossils were treated with magnesium oxide (which highlights details on the specimen for photography), photographed, and examined for abnormalities. Additionally, a computer program, ImageJ, was used to measure the dimensions of the specimens and their abnormalities.

Results: L. sigillum specimen was found to have a U-shaped ident on the upper left side of the body. The Zacanthoides specimen was found to have a U-shaped indent on the lower left side of the body. The first A. wheeleri specimen was found to have an L-shaped indent on the lower left side of the body, and a U-shaped indent on the upper left side of the body. The second A. wheeleri specimen was found to have a small injury in the middle of the right-side of the body. The first E. kingii specimen was found to have a W-shaped indent along most of the left-side of the body. The second E. kingii specimen was found to have a V-shaped indent in the middle of the right-side of the body. The O. debuchii specimen was found to have a W-shaped indent towards the very bottom of the body. None of the specimens possess abnormalities that indicate damage due to genetic malformations or sickness. Therefore, it is likely that the abnormalities on these fossils are from injuries. Previous studies have shown that these types of indentations are usually a result of failed predation. Therefore, these abnormalities in the specimens described above (i.e., the indentations; Fig. 1) are concluded to be evidence of failed predation.

Figure one shows photographs of two E. kingii fossils. The fossils are oval shaped with rounded heads and bottoms with defined ridges (spines) across the thorax. The fossils are about 30mm in width. One of the fossils has a W-shaped indent along most of the left-side of its body. The other fossil has a V-shaped indent in the middle of the right-side of its body.
Figure 1: Pictures 1 & 2 show an E. kingii fossil with a W-shaped indent on spines one through seven on the left-side of the thorax (middle section). Pictures 3 & 3 show an E. kingii fossil with a V-shaped indent on spines seven and eight on the right-side of the thorax.

Why is this study important? This study is important because it provides insight into the environment from which these trilobites come from and how the predators in this environment would have operated. For example, this specimen of L. sigillum is the first known case of an injured trilobite from the Beetle Creek Formation, and only the second case of predation from the Beetle Creek Formation (middle Cambrian). Additionally, the abnormalities (injuries) on the L. sigillum indicate that durophages, which are predatory animals that consume organisms with harder exteriors, like trilobite exoskeletons, were likely present in the environment. Furthermore, the A. wheeleri described in this study is the first documented injury on this genus and species of trilobite, which indicates that A. wheeleri may have experienced higher rates of predation than previously believed.

Broader implications beyond this paper: This study is a prime example of how past environments can become clearer with closer examination of fossils. Fossils are one of our best available methods of piecing together the puzzles of the past. As stated before, the injuries on the L. sigillum indicate that durophages might have been present in the environment, which tells us more about how trilobites functioned as prey in the middle Cambrian. Predation rates in the middle Cambrian are not currently well understood, so this evidence adds more information to what is currently known. 

Citation: Bicknell, R., Smith, P., Howells, T., & Foster, J. (2022). New records of injured Cambrian and Ordovician trilobites. Journal of Paleontology, 96(4), 921–929. doi:10.1017/jpa.2022.14

Kniya’s SciComm for SciOD Reflection

AdrianeLeave a comment

Science communication is an often overlooked aspect of science, with most scientists focusing on the research rather than sharing their findings. When they do share it, it is often coded in difficult-to-understand jargon which limits who can understand what is being explained to them. This is not good. What is the purpose of doing science if what you are discovering is not accessible to be shared with others? 

The main problem when it comes to science communication is that most scientists will act as their mentors when it comes to teaching and leading. This is not necessarily a bad thing if their predecessors were focused on being good science communicators, but if they were shown to “gatekeep” and only share with those who they think are useful there is a high chance that they will not be the best science communicators. Thankfully I have been able to be mentored by great science communicators who make it a priority to share not only their science but that of their colleagues as well.

This semester I had the privilege of taking Dr. Adriane Lam’s science communication course, where I have been able to learn how to be a better scientist, not just in the lab but in the real world. Her class gave me more insight into how to talk to my friends and family about what I do for research and the importance of it. Talking with the guest lecturers, like Dr. Sarah Sheffield, opened my eyes to the importance of science communication by giving me more insight into how just by changing your language and tone, you can communicate science to those who are a little bit more reluctant to listen. Before, I felt it was too difficult to explain what I do because it is not “revolutionary” and geology is not always seen as a primary science, meaning it is a bit unknown to the general public. So explaining glacier mechanics did not seem like the best use of time but now I will try to take caution when explaining my work by using easier-to-understand language and when met with resistance to change my tone so that my work comes across as more understandable.