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Yearly Archives: 2018
September 15 is National Online Learning Day. Now that everyone should be well and truly back to school, I thought it would be a good time for a few miscellaneous notes on various resources.
Evolution: A Course for Educators. American Museum of Natural History via Coursera. Learn about evolution from an expert at one of the best places in the world to study it. Taught by Dr. Joel Cracraft, the course will cover everything you need to teach evolution well. The course is free and offers a paid certificate for teacher professional development hours. It is four weeks long and requires 5-8 a week. It begins October 1st, so you will be done by Halloween.
Introduction to Human Evolution. Wellesley College via edX. A subject that is endlessly fascinating, but seldom taught in schools. Learn about the origins of us from an expert. Taught by Dr. Adam Van Arsdale, the course is self paced, meaning you can start when you want. It takes 4-6 hours for four weeks and is free.
Paleontology: Theropod Dinosaurs and the Origin of Birds. University of Alberta via Coursera. A five week course headed by the esteemed dinosaur expert Dr. Phillip Currie on the anatomy, diversity, and evolution of theropods leading to birds. They offer a paid certificate for those needing the credit. Expect to spend 4-7 hours a week on the course. The course is free, but it started September 12, so join up now before you get too far behind.
Paleontology: Early Vertebrate Evolution. University of Alberta via Coursera. This course covers the evolution of vertebrates through the Paleozoic Era and is taught by Dr. Alison Murray. This is a four week course with an expected 3-5 hours per week. This course is free, but offers a paid certificate for those who need the credit. This course also started September 12th, so sign up now.
Dinosaur Ecosystems. University of Hong Kong via edX. A six week course on dinosaurs in their habitats. The course is taught by a collaboration of Dr. Michael Pittman and Dr. Xu Xing, along with other guests, all with an abundance of expertise on the topic. As a bonus, the course includes the work of one of my favorite paleoartists, Julius Csotonyi. The course requires 1-2 hours a week, so not a big time commitment. It is free, although it does offer a paid certificate for those who need the credit, and starts October 4th.
Dino 101: Dinosaur Paleobiology. University of Alberta via Coursera. Another course by Phil Currie, along with Dr. Betsy Kruk. This is a great introduction to dinosaurs. It is 12 weeks long and requires an estimated 3-10 hours per week, so expect more out of this course. The course is free and starts September 29th, so get signed up now.
Origins – Formation of the Universe, Solar System, Earth and Life. University of Copenhagen via Coursera. Learn how it all began by Dr. Henning Haack. This course is 12 weeks long and expects 5-7 hours a week. The course is free and starts September 17th, so don’t waste time signing up.
There are several more available. If you go to any of the course links shown here, they will guide you to other related courses that are available.
Tetrapod Zoology. Darren Naish has kept his blog, often abbreviated to TetZoo, for over a decade. Through all the years, he has provided multitudinous essays on a variety of animal groups, both extant and extinct. Sprinkled in are also essays on the truth of cryptids (Bigfoot, Nessie, and the like), paleoart, and other topics. Sadly, the blog at Scientific American has closed up shop. But don’t panic, because it has moved to another location. He has set up shop under his own banner at Tetzoo.com. Time to change your bookmarks.
Beautiful Minds. Scott Barry Kaufman has been writing a Scientific American blog about psychology off and on. He recently announced an upgrade to the blog allowing him to have a weekly online column, so expect more articles about human nature from him.
Science Sushi by Christie Wilcox has always been one of my favorite blogs. While I am not a marine biologist by any stretch, she has always been interesting to read. So it is sad to report her Discover blog is closing up shop. She is moving to ScienceSushi.com, but will not be adding regularly to it. She will continuing to write, so keep an eye out for her on the sites she lists in the post linked to here.
Dataset Search. You’ve heard of Google Search, Google Scholar, Google Maps, and a plethora of other ways Google lets people search the web. Now meet Dataset Search, for when you are trying to find data that has been published or stored online. This searches for data files or databases according to how they are identified, not by what is in the file.
Science without publication paywalls: cOAlition S for the realization of full and immediate Open Access, by Marc Shiltz. PLoS Biology. 2018. This article discusses Plan S, a proposal by a coalition of European leaders to make science articles free for everyone. In their words, “no science should be locked behind paywalls!” (emphasis theirs).
Seriously, Science? A great blog on Discovermagazine.com that covered weird and humorous published research has been canceled. No word on why, the authors just said they were informed they would no longer have a slot on the blog roll. So long, Seriously Science, it was good to have known you.
Return to Reason: The Science of Thought, by Scientific American. 2018. This ebook is a collection of essays discussing why facts don’t seem to matter to people or help persuade them and what we can do about it. Well worth a read.
Timefulness: How Thinking Like a Geologist Can Help Save the World, by Marcia Bjornerud. Princeton University Press. 2018. Most people can barely remember what they had for breakfast yesterday. We really aren’t well equipped to think about time on the scale of millions and billions of years. Dr. Bjornerud has written a great book to help people come to grips with the immensity of time. I highly recommend it.
Underbug: An Obsessive Tale of Termites and Technology, by Lisa Margonelli, Scientific American/Farrar, Straus and Giroux, 2018. This book is not really about termites. The study of termites is used as an illustration of scientific inquiry and the questions that researchers come across during their studies. There are questions about the termites, but also about how science is done and about humans viewed through a different lens.
Darwin and the Making of Sexual Selection, by Evelleen Richards. University of Chicago Press. 2017. This book tells the story of how Darwin figured out problems with natural selection by coming up with sexual selection. To my mind, sexual selection is a subset of natural selection, but it is generally viewed as separate, with natural selection being success based on fecundity and survival of offspring, whereas sexual selection deals with the choices of mates. However you look at it, sexual selection is an important concept and this book explores the origin of that idea.
The Dinosaur Artist: Obsession, Betrayal, and the Quest for Earth’s Ultimate Trophy, by Paige Williams. Hachette, 2018. Williams tells the story about a skeleton of a Tarbosaurus bataar, what could be described as a Mongolian Tyrannosaurus rex, and the long and confusing battle of who owned it and where it would eventually reside. The worldwide fossil trade is a morass of differing opinions, laws, and money. This book attempts to tease apart the strands to answer the question of who owns fossils.
Through a Glass Brightly: Using Science to See Our Species as We Really Are, by David P. Barash. Oxford University Press, 2018. As the great physicist Richard Feynman said, “The first principle is that you must not fool yourself–and you are the easiest person to fool.” Humans are masters of deluding ourselves, but science helps us remove the wool we place over our eyes to see things, and ourselves, as we truly are. Only then can we become the people we see ourselves as. That is the goal of evolutionary biologist Dr. Barash in this book.
The Book of Why: The New Science of Cause and Effect, by Judea Pearl and Dana McKenzie. Basic Books, 2018. A big problem that any educator sees is the rather unbelievable lack of understanding many people have about cause and effect. Please get this book and teach people about how cause and effect works. Since this book relates the science of cause and effect to robots and artificial intelligence, it will be the perfect addition to tech classes.
I think that is enough for now. It is certainly enough to keep you busy if you try even a few of the many offerings available for furthering your education or just indulging your curiosity. Enjoy. If you try them, come back and let us know what you thought of them.
With all that has been going on in the world and all the important societal problems, I have been despairing that my desire to push for a natural history museum and more evolution education seemed not as important. But it struck me today that it is perhaps one of the most important things we need to do. There are a lot of misunderstandings about evolution, even among people who accept it, that hinder our ability to get along in the world. Understanding two important truths of evolution will go a long way towards healing our societal divides. What are those truths? 1. We are all the same, and that is a good thing. 2. We are all different, and that is also a good thing. These may seem contradictory, but if you understand how they are meant, they make perfect sense.
- We are all the same, and that is a good thing.
When you start really studying life on this planet, it quickly becomes inescapable that we are all connected. We are all part of the same family. Strip off the skin from humans and we see essentially the same underneath. We all share the same skeletons, our muscles and organs are the same, there are no important differences in our brains. Sure, there are differences, but no matter what way we try to divide humans, especially by skin color or nationality, we find that the differences within the groups are greater than the differences between groups. What this means is that the dividing lines are arbitrary and have no biological basis.
When we go beyond humans and look at all vertebrates, we see the same thing. If we compare skeletons, we see the same bones over and over again. Every animal that has four limbs shares the same bone structure. They may look different, but the bones are all the same. All of our front limbs have a humerus, an ulna, and a radius. We all have the same number of fingers and toes. They may look different, they may lose some as they grow from fetus to adult, but they are all there. As we get farther and farther away from direct ancestry and relationships, the superficial differences start piling up, but the core is always the same.
Going even farther, we all share the same base code. We all use essentially the same DNA and RNA. The sequences may be different, but just as all computer programs are different, they all share the same underlying coding language. We all share metabolic pathways, from bacteria to humans.
Why do we see all these similarities? Because we all share an ancestor. Somewhere down the line, we are all related. We are one family. It may be a very extended family, but we are all together. All life on Earth is connected. Through that life, we are all connected to the very rock upon which we stand. Life has shaped the surface of the Earth. It has shaped the air we breath. We all sprang from the same roots. When you look at someone from a different culture, someone with a different skin color, you are not seeing an other, you are seeing a long separated family member. Embrace that connectedness. Now, I know that no one can get more under your skin and angry than a close family member, but at the end of the day, we don’t generally let that tear us apart. No matter how much we may disagree with our family, we still recognize they are family. Just take that feeling and extend it to recognize that every living thing on Earth is also part of your family.
2. We are all different, and that is a good thing.
So if we are all essentially the same, how can we all be different? No matter how closely we are related to someone, there are always differences. Even identical twins are not completely identical. Our DNA and life experiences mean that each and every one of us is different in some way from everyone else. While we all share the same basic body plan and organization, there are always some differences.
Those differences are important. Ask any agricultural scientist and they will tell you that one of, if not the biggest danger in our food supply is the monoculture crops we grow. When everything is the same, that means they also share all the same limitations and vulnerabilities. Monocultures only work when there is no change. But they do not handle change well. And if there is one thing we know about life, it is that change is inevitable. These days, we are pushing change faster than ever before, so this vulnerability to change is deadly.
Purity is the death of a species. We need diversity to weather changes. As new diseases crop up, as weather becomes more unpredictable and changeable, we will need the diversity to be able to handle whatever is thrown at us. The more diverse the population, the more changes we can tolerate. In a diverse population, there will always be some fraction of the population that is prepared for anything that happens. Those people will make sure that we continue. Moreover, they will help those of us unprepared for the changes make it through. When a new disease appears, those that are naturally immune will be key to developing medicines that will allow the rest of us to survive. Those that can handle climatic changes will be the ones to build the structures and infrastructure that will allow the rest of us to weather the storms. We need diversity. If we try to homogenize our culture and our people, we will die.
We need evolution education and a natural history museum.
So how do we get people to understand this? First of all, on a broad scale, we need to teach people a proper understanding of evolution and evolutionary theory. But we have to do it in a way that exemplifies its importance in our everyday lives. We need to get people to understand why they need to understand it. Evolutionary theory affects us every day. People need to understand how.
We need natural history museums for a multitude of reasons, but two very important ones apply here. First, they will stand as storage houses of information. They are a public recording of the changes that have taken place and are taking place. Secondly, they are a way to teach people who are not in school. Even if they don’t pay that much attention to the details in the museum, they will see a record of the changes. Museums can be designed to showcase the importance of evolution, the advantages of diversity, and the dangers of reducing that diversity. Museums are one of the most trusted sources of information. We need to leverage that to showcase both the interconnectedness of life on Earth and its diversity and why that has allowed its continued existence. It also can showcase what happens when that diversity is not there.
One may argue that history museums would be better at this. The advantage of history museums is that it makes it personal and easy to make it easy for people to relate to it. The disadvantage is that it makes it personal and easy for people to get defensive about it. Natural history museums can teach these lessons on a canvas that people can view and learn from more dispassionately, without it feeling like a personal assault upon their culture that can often happen in history museums.
To be sure, many people will feel that any mention of evolution is an assault upon their worldview, so I am not advocating the idea the natural history museums are inherently better. Instead, I am advocating the view that all types of museums work better when there is a diversity of museums that can tell the stories from different angles. Without a natural history museum, we lack an important viewpoint in the public arena. By building a museum network, we can spread the ideas much more effectively. A natural history museum will not hurt other local museums. It will help all of them. We don’t need just a natural history museum. We need a natural history museum, a local history museum, an international history and cultural museum, an art museum, and other museums. In Arkansas, we have some of the history, art, and culture, but we do not have a natural history museum. As such, we lack that long and broad view that can only come from an understanding of natural history.
I was reading a post by Brian Switek on his blog Laelops—which by the way, if you aren’t reading it, you should—about interpreting injuries on dinosaur bones. It’s an interesting read, but what caught my eye was a problem that I have seen in more places than I can count. He included this picture in his post. Take at look at the front limbs.
The “hands” are pointed inwards. To get in this position, the elbows have to be turned outwards, using a rotation in the shoulders. But it also requires the hands to be pronated. To get what I mean by that, hold your hands forward with the palms up. When you do this, the two bones in your forearms—the ulna and the radius—are positioned side by side.
This position is called supination. Pronation requires the radius to rotate so that it crosses over the ulna. This can be done because of the construction of the elbow. The ulna is essentially the entire elbow joint, making it a hinge type joint. The radius is, for the most part, just along for the ride at the elbow. The head—the part at the elbow—is round, with a shallow indentation, which is surrounded by what is called the annular ligament. That ligament wraps around the radius, attaching it to the ulna, but never actually attaching to the radius itself, allowing the head to spin in the sling. It is that shape of the radius and the annular ligament that allows it to rotate freely, which makes our level of pronation possible.
Importantly, all tetrapods have the same bones. It was set in place from the first fish that developed bones to support their fins and remains that way all through the hundreds of millions of years to us today. However, not all animals have the same shape of the radial head. Some animals appear to not have both bones, but in reality, they do. They have just fused the bones together. But that fusion has consequences, just like altering the shape of the radial head.
Before we move on to dinosaurs and those consequences, it would be reasonable to ask about other animals to see if they show the same pattern. Let’s take a look at proboscideans, the family of elephants. They are large animals that have their palms facing downward.
This is an elephant skeleton on display at the Manchester Museum. They have a radius and ulna, just like humans. Theirs, however, do not swivel. Nevertheless, it is rotated so that the bones are not in parallel, but the two ends are twisted so that the radius is twisted over the ulna. Their forelimbs are in permanent pronation.
So what about dinosaurs? Let’s look at Dreadnaughtus, the giant sauropod.
This is Figure 2 from Lacovara et al. 2014. The radius and ulna are massive, as befits a giant quadruped. They are also incapable of rotating to pronate the foot. It has been said by some that some degree of pronation is required for efficient quadrupedal locomotion, but that is not really accurate. It does mean though, that the first digit, what would be our thumb, is going to face forward or at most slightly inward while the remaining digits will be angled outward (anterolaterally). They will not be situated directly forward without shifting the arms at the shoulder. As an example, here is a figure showing a sauropod trackway. Note the direction of the toes.
This is a figure from Falkingham, et al. 2010. As can be seen, the toes are not forward, but pointing outward. The level of pronation is minor and can be achieved with only rotation at the shoulder and a minimal shift or the forelimb. VanBuren and Bonnan (2013) found this was true in all quadrupedal dinosaurs.
This is a best case for pronation in dinosaurs and they can’t do the full pronation needed for bunny hands, much less the bizarre inward facing hands of the Plateosaurus above. So let’s look at theropods, where we see bunny hands all the time. For instance, in Jurassic Park pretty much all the dinosaurs have bunny hands.
The palms are downward with the arms close in, requiring a full pronation to achieve that position. So could they do it? To the bones. This is the radius of Neuquenraptor, as published by Novas and Pol in 2005. It is an unenlagiin, in the family Dromaeosauridae, along with Velociraptor, Deinonychus, and all those other raptor dinosaurs.
These radius is fairly straight, and if you look at the head, it is not the shallowly indented round cup we see in mammals. It is more angular, which is typical of theropods. That relative angularity would prevent the radius from rotating as ours do, in effect locking it into a small range of motion, preventing them from placing their hands palm down.
In point of fact, VanBuren and Bonnan didn’t just look at sauropods. They looked at all types of dinosaurs. They found that no dinosaur had the ability to cross the radius over the ulna, which means that at best, they had very limited ability to pronate their forearms. That means no known dinosaur could have characteristically held their arms close in with their palms facing downward, aka bunny hands.
It is a little more complicated than this. Studies have shown that if the arm is fully extended, the hands can be more pronated, by using the entire length of the arm to rotate, but even that is not going to be fully pronated like we can, or bunnies can. And if you think about the living dinosaurs, the birds, when was the last time you saw a bird put its wings flat on the ground in front of them? They can clap, but they can’t type or play basketball.
Of course, the wrist bones of the maniraptors—those dinosaurs leading up to birds—did have what is called a semilunate carpal bone, allowing them to move their hands to insane degrees side to side, which is what allowed them to develop the ability to fold their wings like they do, and they can flex and extend their hands to a remarkable degree. But they cannot rotate their wrist. Try it yourself. See what movements you can make with your hand without moving your forearm, just your hand. However far you can move your hand that way, these dinosaurs have you beat in spades. But once you move that forearm, you have a serious advantage over them.
Back in the old days, before the idea of museums being educational centers became commonplace, most museums were more like some rich person’s trinkets collected during vacations packed into glass cases so people could see them. They rarely had signs telling people what anything was, nor was there oftentimes any attempt at organization. Because of the rather haphazard and all-encompassing nature of the displays, they got the name Cabinets of Curiosities.
As time went on, they became more thoughtful and organized, with more attention being spent on telling people what the objects were, teaching people about them, and properly preserving the objects for posterity.
The Old State House Museum in Little Rock honors that tradition with an exhibit called “Cabinets of Curiosities: Treasure of the University of Arkansas Museum Collection.” I am sad to say that the exhibit has been up since March 11 of 2017, but I have only recently learned about it and have gone to see it. Truth be told, the only reason I found out about it was because I went to the University of Arkansas at Fayetteville to see the Hazen Mammoth fossils and found that the lower jaw of that mammoth was on display in Little Rock.
The reason I am sad to say this is because the exhibit is well worth your time to go see. If I had known about it earlier, I would definitely have discussed it here by now. I was told it will still be at the museum for another year, so you still have time. It is free, so go. Spend a Saturday downtown and explore the exhibit. Then go see what else is down there, which is plenty to keep you busy over the weekend.
What will you see when you are there? To begin with, you might want to ask directions from their helpful and friendly staff, because the exhibit is upstairs in a side gallery that you might miss if you didn’t know it was there.
The objects are from the University of Arkansas Museum at Fayetteville, which, sadly, closed its doors in 2003. As a result, if you want to see their collections, you have to make an appointment to see the warehoused collections. Or you can see a small part of them in this exhibit. The museum had collections from all over the world covering many subjects, which the exhibit honors by having selections of a wide range. It is like a mini-museum of anthropology and natural history.
I am a fossil guy, so I am going to focus on the fossils you can see. The fossils are mostly in the first two rooms that you enter in the exhibit. In the first room, under the horns of a large cervid (the family containing deer, elk, and moose), are two cabinets of invertebrate fossils and minerals. There are some nice fossils to see. You can see a crinoid with the calyx, or body, and pinnules, or “fronds”. These are much rarer than the pieces of stalks we normally find throughout the Ozarks. There is also a starfish, ammonoids, and nice plant fossils, among others.
To the right of this display is a cabinet containing the skulls of a musk ox and Smilodon (saber-toothed tiger), a couple of large, straight-shelled nautiloids, and one of the bones of Arkansaurus, which up until very recently, was the only known dinosaur found in Arkansas.
On the other side of the room, you can see the bones of an elephant leg and a cabinet full of geology specimens, including one enormous quartz crystal that would not be allowed as a carry-on for some planes because it is too big to fit.
The next room contains case with the leg bones of a camel, lion, dog, and cat. It also contains the pieces of mammoth that I came to see. But before you get to that case, you have to pass a giant clam that could fit a child, or even a small adult if they curled up.
The other side of the room contains the skulls of a bison and rhino, a whale rib, and an entire icthyosaur from Germany. The end of the room has the skulls of a bear and walrus, complete with tusks, and the skeletons of a bat and snake.
The final part of the fossil and biology section that I was most interested in was an old display of horse evolution. If made today, it would probably look substantially different because of all the new data we have gotten since that display was made; but except for a few very minor details, the essential facts would be the same.
Of course, there is much more to the exhibit than what I have presented here, such as this cool whalebone armor and cavalry sword, so spend some time checking out the rest of the exhibit and the museum.
There is one thing that the exhibit could have capitalized on, but didn’t (mainly because they didn’t know about it, but also because they were trying to stay with the whole cabinets of curiosity motif), was that many of the fossils and biology specimens have fossil counterparts that have been found in Arkansas. For instance, we have fossil Smilodons, musk oxen, whales, several mastodons, giant deer and giant snakes, and much more.
So here is my question to you. How many people would pay for a special tour of the exhibit that discussed all the cool Arkansas fossils that matched up with the ones on display here. How much would you pay? $10/person? More? Less?
On March 12-13, the south-central section of the Geological Society of America held their annual meeting in Little Rock, Arkansas. During that meeting, a session was held on paleontology in honor of Arkansaurus fridayi being named our State Dinosaur, even though it has never been officially scientifically named and it being the only dinosaur that has ever been found in Arkansas other than tracks. That all changed during the meeting. This post will focus on the Arkansas dinosaurs (yes, plural, that was not a typo). A later post will cover more fossil announcements.
The first talk on Arkansas dinosaurs came from our very own Dr. Rebecca Hunt-Foster, who did the initial work on Arkansaurus. She has a new paper that came out right after the meeting. She announced that Arkansaurus fridayi is now the officially recognized scientific name for our dinosaur. She also discussed her findings confirming it as an ornithomimid, one of the bird-mimics, like the Gallimimus made famous in Jurassic Park. That had been the first tentative identification, but her work previously showed that it did not match with other known North American ornithomimids. However, that was from a total known collection of nine specimens. We now have almost two dozen ornithomimids known from North America. When she compared Arkansaurus with the new material, she was able to confirm that the initial identification was indeed correct. Moreover, it showed that ornithomimids had the ability to disperse across the continent at the time. The Late Cretaceous interior seaway that bisected the continent had not yet closed off access by then.
Dr. Celina Suarez from the University of Arkansas at Fayetteville provided the most astounding talk of the session (ed. this was a repeat of the talk she gave at the national GSA meeting in Seattle in 2017). We knew we had titanosaurs and acrocanthosaurs in Arkansas from their foot prints. Now we have their bones as well. She presented a description of the first known Mesozoic multi-faunal vertebrate assemblage in Arkansas. In other words, she reported a collection of fossils that contained several different species. The fossils were found in Howard County within the Holly Creek Formation, a part of the Trinity Group that underlies the DeQueen Limestone. This is the same site which became famous for its dinosaur tracks.
Among the fossils included pieces of a titanosaur that is probably Sauroposeidon, one of the largest dinosaurs ever known. They like to call it Paluxysaurus in Texas, but further work has indicated that Paluxysaurus is a junior synonym of Sauroposeidon found in Oklahoma and now Arkansas. She also found pieces of an Acrocanthosaurus. For those who are not familiar with this dinosaur, it is a carcharodontosaurid, the same family as Giganotosaurus. This family is within Allosauroidea, the group containing Allosaurus and all its kin. Acrocanthosaurus was almost the size of Tyrannosaurus rex and with a small sail or ridge along its back and was the dominant predator of its time.
That isn’t all though. They also found scutes from an ankylosaur. While it isn’t a lot, Kristy Morgan, one of her students, was able to determine that they likely belonged to a nodosaurid ankylosaur either most closely related to or actually was Borealopelta, a dinosaur from Canada just named in 2017 from the best preserved dinosaur fossil ever found.
Finally, pieces of two other theropods were found. They found pieces identified as Deinonychus antirropus, Velociraptor’s big cousin, as well as Richardoestia. Deinonychus is well known as the archetypal dromeosaur, the dinosaurs with the famed sickle-clawed toe. Richardoestia is much less well known, making this identification curious. All that is really known of this dinosaur is a set of jaws and some isolated teeth. Three species have been named, but at least one has been suggested to be a sebecid crocodylomorph. It is likely that once more of this genus is discovered, some or all of the species will not survive, at least as they are now. But for now, we will count it as an Arkansas dinosaur until shown otherwise.
This just touches on the fossils found in this assemblage. We now have a much bigger glimpse into Cretaceous Arkansas. Stay tuned for more. For now, we can say that southwest Arkansas 120 million years ago looked something like this.
Three years ago, a ten year old boy was visiting a monastery in Colombia. Being a curious boy, he looked around at his surroundings. He could have done like others have done for centuries and not paid that much attention to the stones upon which he walked, but he didn’t. He noticed a curious fossil fish in one of the flagstones. Most people, if they noticed it at all, would have simply given it a passing nod of interest. He, on the other hand, took a picture of it and sent it to the local Paleontology Research Center to see if they knew what it was.
Firstly, I amazed they even had a local paleontology research center, most places don’t. Secondly, it is amazing that the boy took the time to bring it to their attention. Thirdly, it is amazing that someone there noticed what they had and brought it to the attention of the needed experts. All these amazing, unusual occurrences have resulted in an article in the January 31 edition of the Journal of Systematic Paleontology detailing the new fossil species discovered by that boy. Sadly, no one knows how to contact him to let him know about the publication. The researchers have his name and email, but have apparently been unable to contact him to give him his copy of the paper about his fish.
The fish he discovered was named Candelarhynchus padillai, after the Monastery of LaCandelaria near Ráquira, Colombia, where it was found. The stone for the flagstone came from a nearby quarry. According to the authors of the paper, the rocks in the quarry corresponding to the flagstones were “fossiliferous, finely laminated, light to dark grey, indurated mudstones ofthe lower-middle Tuonian San Rafael Formation…” The rock strata also contained numerous plankton, ammonites, clams, and crabs; so quite a rich fauna. The Turonian is 89.8-93.9 Mya, according to the latest GSA time scale, so we are talking roughly 92 Mya.
The fossil is excellently preserved, with slabs containing both part and counterpart, meaning that when they split the slab, pieces and impressions were left on both sides. The whole body can be seen, with nice detail around the head, as well as impressions of the soft tissue portions of the fins. At 27 cm (just over one foot), it is a decent-sized fish. It’s a thin fish, with a long skull full of tiny, conical teeth. It was clearly a fast-swimming predator, and likely prey for a lot of larger species.
The reports on the fish said that it does not have any living relatives. That is true, in a way, but also not. The specific family the phylogenetic analysis placed it in is Dercetidae, an extinct family that all died out in the Cretaceous. However, if we look a bit broader, it is in the Order Aulopiformes. This order is mostly known for a variety of mostly deep water fish known as lizard fishes, which is why all the news reports of this find have said Candelarynchus was a “lizard fish.” Even though it is in the same Order, it is not in the same family as any of the modern lizard fish.
But the title of this post mentioned Arkansas and I have thus far not done so. Vernygora reports that current analyses of fossil aulopiforms include three main families: the Dercetidae, Halecidae, and the Enchodontidae. One of the most prominent Cretaceous fish from Arkansas is Enchodus, commonly called the “saber-toothed herring.”
This is a terrible name because Enchodus has nothing to do with herrings. It was at one time considered part of Salmoniformes, making it closer to salmon. However, more recent analyses have consistently placed it in Aulopiformes, specifically within the Enchodontidae, making it closer to lizard fish. This makes a good deal of sense to me because, if you add the fangs from a payara, commonly known as the vampire fish, onto a lizard fish, you have pretty good idea of what Enchodus was like.
Fossil lizard fish then were quite abundant in the Late Cretaceous in both worldwide range and diversity. They may not be the most recognized fish today, but they have a long history and make for great fossils that can be found in a lot of places, including southwestern Arkansas.
Did you know that Arkansas once had catfish more than three meters long and weighing, depending on who you believe, as much as 450 kg? That makes the world record catfish of today look positively puny.
The proof can be found at the Arkansas Geological Survey. The skull of one such monster is on display in the second floor display case. It was found in 1983 off Highway 79 near Camden. The bones were pulled from the Claiborne Formation, or more specifically, the Sparta Sand.
The Claiborne Group can be found in much of the South-Central part of the state, as well as on Crowley’s Ridge. It is Eocene in age (34-56 Mya). According to the Arkansas Geological Survey, the Claiborne is primarily non-marine and is comprised of mostly fine-grained rocks ranging from silty clays to medium-grained sandstones, with the occasional lignitic coal bed. The shales usually have the variegated tans and grays often seen in terrestrial sediments, with brown and black organic-enriched layers intermixed. Fossils are common from the units, with plant fossils common, as well as trace fossils. Of particular interest here are the reptile and fish bones that have been found here.
The Sparta Sand in particular is a thick bed that can be several hundred feet think. It is a fine to medium-grained sandstone that is typically light-colored, either a whitish or light gray, with thin beds or brown or grayish sandy clay and lignite. It has been considered an important aquifer for the region. The sediment is thought to have been laid down by rivers during a regression of the marine shoreline farther south. In other words, we are looking at the flood plain of a river meandering its way to the ocean, much like southern Arkansas and Louisiana is today. Only back then, the catfish grew much bigger than they do now.
So what do we know of this fish? We know it was a siluriform catfish, most likely in the Ictaluridae family, along with all the other North American catfish. It was probably something like the giant Mekong river catfish and lived in similar environments. The Eocene was warmer than it is now, so it was likely even more tropical than it is today. Beyond that, we don’t know a lot. The fossil has never been fully studied and described as far as I am aware. In 1983, Dr. John Lundberg, a noted expert in fossil catfish and currently chief curator at the Academy of Natural Sciences of Drexel University, corresponded with the AGS about studying it, but thus far, I don’t know what, if anything, came of it.