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Time for another Mystery Monday fossil! See if you can figure out this wrinkly rock.
I hope you had a blast over Spring Break. Here is a fossil you might find in Northwest Arkansas. See if you can figure out what it is.
Mystery Monday this week fell on St. Patrick’s Day, so to celebrate, the following image was posted for the mystery fossil of the week.
St. Patrick was well known for driving all the snakes from Ireland, at least so the myth goes. In reality, there never were any snakes in Ireland for St. Patrick to drive out in the first place. But unlike Ireland, Arkansas has always had snakes. Right now, we have a diverse population of snakes, including boasting more different types of venomous snakes than most other states, being one of only ten states that have all four types of venomous snakes in the country (there are roughly twenty separate species, but they all fall into four main groups). Here you may find the copperhead, coral snake , cottonmouth (aka water moccasin), and the rattlesnake (including the Timber, Western Diamondback, and pygmy rattlers). At least we can take comfort that we are just outside the ranges of the Massasauga and Eastern Diamondback rattlesnakes and we don’t have the diversity of rattlers seen in places like Arizona and Texas (which may win the prize for most venomous snakes in the country if both species number and diversity are taken into account).
In the past though, we also had other snakes, including Pterophenus schucherti, also known as the Choctaw Giant Aquatic Snake, a giant sea snake that lived here in the late Eocene roughly 35 million years ago. The Eocene was a much warmer time. In fact, this period falls at the end of what is called the Palaeocene-Eocene Thermal Maximum. There were no polar ice caps during this time, with at least double the amount of carbon dioxide and triple the amount of methane than what we see now. Because of this, Louisiana was pretty much under water and Arkansas had wonderful ocean front property, along with a lot of swamps and marshes. It is likely the cooling during this period into the Oligocene Period, that caused the extinction event that wiped out these snakes, along with several terrestrial mammals, including a variety of Perissodactyl horse ancestors, artiodactyls (cloven hoffed mammals), rodents, and primates.
This was the perfect environment for a number of different snakes, although we don’t have fossil evidence of many. One that we do have is of Pterosphenus. This snake had tall, narrow vertebrae, indicating adaptation to an aquatic lifestyle. In fact, it probably was not able to support itself on land very well due to its thin body.
Sea snakes today rate as some of the most highly venomous snakes in the world. However, there are nonvenomous ones as well, such as the marine file snake, Acrochordus granulatus, which live in coastal regions between Asia and Australia. Those of today are relatively small snakes, ranging from half a meter to just over 2 meters (2 feet to 7 feet or so). Pterosphenus, on the other hand, reached lengths of 2.3 m to 5.1 m, or possibly larger.
Unfortunately, we don’t know a whole lot about these snakes, other than they were clearly aquatic. The bones that have been found with them, such as whale bones, have indicated marine waters. Fossils of these snakes have been found in eastern Arkansas, in Faint Francis County in the Eocene deposits around Crow Creek called the Jackson Group.
It’s another Monday! You know what that means, right? The end of the weekend, an extra dose of coffee to get the day started, and a new fossil for Mystery Monday. Today’s fossil is a very common fossil in Arkansas. Some people think these fossils form a kind of spooky face. Bonus points if you can say where the picture came from. Once I tell you what it is, you should check out all the other cool info they have.
Many people have an issue with scientists, particularly those studying evolution and paleontology, for making statements they feel are pure speculation. I absolutely agree that people should be upfront about what is known and what is speculation. Most scientists ARE generally clear about that. If you ask most scientists, they will tell you what we know and don’t know. That is actually one of the biggest problems that scientists have with almost all of the shows and most of the books written for the public. Those outlets are not clear about what we really know and what we don’t, what is speculation. Most scientists I know work really hard at trying to clarify that sort of thing and get very frustrated when their words are twisted around. Many scientists have refused to work with film crews for precisely that reason. So please don’t blame the scientists. Write to the shows and demand they are clear about their speculations.
Sadly, I wish I could say all scientists act this way, but it is true, not all do. Scientists are only human after all. There are problems with some scientists. Believe me when I tell you that we recognize this and try to stop it. The lab I worked in to get my doctorate had a reputation for being spoilers, as it were, because a large portion of our research involved figuring out the limits of what the data really let us say and then telling others no, you can’t say that because the data do not extend that far. Our work was very much about separating speculation from reasonable interpretation and fact. But we were hardly alone in that regard, it is something most scientists work hard to do. Paleontology is admittedly one of those fields in which it is easy to take the fossils we have and in our excitement try to say too much about them. So we do our best to restrain ourselves and other workers from extrapolating too far. Go to a paleontology conference and you will see that on display in abundance.
Unfortunately, that rarely shows up in material done for the public. The film crews and honestly, most of the public, do not want to hear we don’t know. They want to hear the fanciful stories. Most people get annoyed with scientists when they equivocate and don’t give straight answers. We frequently hear from people, well which is it? Is it this way or that way? If you can’t say with absolute certainty one way or the other, you must not know ANYTHING, when in point of fact, there is a vast difference between not being sure and not knowing anything, I am sure most will agree. But most people don’t want to hear we don’t know with certainty, we can only say this much about it. I have even seen that in my college courses. Many students are uncomfortable with the material I cover in which there are no good answers everyone agrees on. They want definitive answers. A large part of that, I think, is that science is taught in schools very poorly, as a list of facts to memorize, not as a way of thinking and an expanding body of knowledge that is constantly re-examined, with large areas we don’t know yet. In fact, and what makes science fun and interesting for people doing it, is that science is more about what we don’t know than what we do. But happily, I can say that is changing in many areas, with the introduction of more hands-on, exploratory teaching methods.
One of the challenges though, is that many things the lay person thinks are pure speculation are not speculation at all, but are backed up by lots of evidence that there is simply not enough time to go into. Many computer programmers simply tell their clients what they do is magic because to answer their questions adequately would take months of training to even get them to the point they could understand the answer. Would you tell a computer programmer what they are doing is pure speculation simply because you don’t understand it? We aren’t trying to be elitest, there is just a lot of information we don’t have time to transmit. There is simply too much going on, too much data, too much research for anyone to keep track of it at all. Even professionals who try to keep up as part of their full-time job can’t do it. So it would be foolish to think anyone who doesn’t spend most of their time studying the research could possibly have a good grasp of the intricacies and quantity of data. It therefore becomes quite the annoyance when people say you can’t know something when they have no idea how much we do know. Many of those things people say we can’t know have been studied for decades by many people who have spent their lives figuring out how to go from speculation to concrete data and hard fact. Most people don’t realize the extreme levels of simplification it takes to get some concepts across because no one can provide all the data backing up those assertions without having their audience earn a graduate degree in the process.
Is all this me telling you to just trust whatever we say? Absolutely not. But don’t expect to come in on the ground floor and know what is going on at the top any more than you could expect to speak perfect French by catching someone speak a few words on TV. Understand that you are only getting the tip of the iceberg. What you see on TV is a seriously flawed transmission of a few grains of knowledge from a mountain range of data. Learn as much as you can from reliable sources. The more you know, the richer your interactions with professionals and the more in depth we can talk to you. We will be happy to share with you everything we know, that’s our job. But what we tell you is highly dependent on the level at which you come to us and the amount of time people are willing to spend. Also understand the quantity of data is more than any one person can understand, even those whose job it is to do so. That is why we have many people studying problems. No one can have all the answers. That is why we keep asking questions. Being open about what we know and what we don’t allows us the freedom to learn more and shows us the path about where to go next. Scientists don’t leave things at speculation, they try to figure out how can we go from speculation to understanding. But if you want to understand all the steps involved, may I suggest grad school?
I have been working on lectures on early amniote evolution, along with the following reptilomorph and synapsid lectures for my vertebrate paleontology course. We will be getting into dinosaurs and the other Mesozoic animals very soon, hooray! However, in preparing these talks, it has brought to my attention just how prevalent two sites in particular are: Reptileevolution.com and Pteresaurheresies.wordpress.com.
When I did a search for “pterosaur”, Google actually responded by saying “Did you mean pterosaur heresies” and provided images that all but one are either from the site or sites complaining about the site.
This is quite unfortunate. Both sites present an abundance of beautiful artwork done by a stellar paleoartist. There is an abundance of information on the animals and their relationships. All in all, the websites look fantastic and are quite the draw for paleo-enthusiasts.
But it is all wrong.
None of the hypotheses presented on these pages is accepted by virtually any other paleontologist. The techniques used to gather the information is not considered valid and no one who has tried to reproduce the data using the methods have had any success.
I won’t get into details about why the websites are wrong. I am frankly not qualified enough to provide a step-by-step breakdown of the problems (not being an expert in either pterosaurs or basal tetrapods), nor do I really have the time. I will say that many years ago, I heard the author of these websites give a talk about his evidence for a vampiric pterosaur and even as a young undergraduate, it was clear to me that neither the technique nor the conclusions were valid. I found it very unfortunate because the idea of a vampiric pterosaur was incredibly cool and the technique, which involves detailed image study, is useful in many contexts. However, it is very easy to let personal biases enter into conclusion based on these methods, to allow oneself to extrapolate well beyond anything the data can actually support. Oftentimes, those biases are completely unknown to the observer simply due to the way our brains interpret sensory input and modifies them based on past experience. We really do not see everything we think we see, which is why the scientific method requires other scientists examining your conclusions and your methods and trying to poke holes in your ideas. So it is vital to recheck one’s conclusions with many detailed images from various angles and lighting methods and, most importantly, detailed examination of the fossil itself.
So instead, I will point you to articles written by people who are experts in the very animals that are discussed on those pages and what they have to say about them. The first is an article by Dr. Christopher Bennett, who is an expert on pterosaurs. In this article, he discusses the validity of the techniques and discusses specific claims of two pterosaurs in particular, Anurognathus and Pterodactylus. Anurognathus is a very odd-looking pterosaur and is quite aptly named “frog mouth.” Pterodactylus is probably the most famous pterosaur next to Pteranodon and is why so many people mistakenly refer to all pterosaurs as pterodactyls. Dr. Bennett does an excellent job critiquing the science in a professional and readable way.
The second article is a blog post by Darren Naish, a noted researcher and science author that has researched pterosaurs and many other animals who has a deep understanding of both the accepted science and the author of these websites and the work presented therein. Here is what he says: “ReptileEvolution.com does not represent a trustworthy source that people should consult or rely on.Students, amateur researchers and the lay public should be strongly advised to avoid or ignore it.” The emphasis is completely his. The post is quite long and discusses several aspects of the work, discussing the accepted science and the material on the websites that is not accurate, including the techniques used to arrive at the conclusions, both accepted techniques and those by the website author that are not.
The next site is an article by Pterosaur.net, a website devoted to research on pterosaurs by pterosaur researchers. It is a brief article that uses Naish’s article as a starting point and continues on with a discussion of why they think it important for people to know why these sites should be avoided. To quote: “The issue taken with ReptileEvolution.com is not that it exists, but that it’s internet presence has grown to the point that it is now a top-listed site for many palaeo-based searches. Tap virtually any Mesozoic reptile species into Google and either ReptileEvolution.com or the Pterosaur Heresies is likely to be in the first few hits. The situation is even worse for image searches, which are increasingly dominated by the many graphics that Peters’ uses on his sites.” This would not be a problem that the sites are so well known if they were correct, but their prevalence presents a highly flawed version of what scientists really think. People are taking these sites as truth, when in fact they are regarded by professionals as seriously wrong.
Finally, Brian Switek, a science writer who authors the blog Laelaps, which moved from Wired Science Blogs to National Geographic and the now-defunct blog Dinosaur Tracking for the Smithsonian, wrote a piece on the site, in which he urged more paleontologists and paleontology blogs to call out misleading websites like these. In that spirit, I hope I can help some avoid getting a mistaken impression of dinosaur science and help steer them to better, more reliable sources.
* If you are wondering why I say “the author” or “the artist” rather than using the person’s name, it is because I don’t want this to be about the person, but the information. I don’t personally know the author, nor have I ever had direct contact, so I have nothing to say about the person. The work, however, can be and should be open for criticism, just like any other researcher, including my own.
One of the questions I get often is what should you do if you find a fossil. I have been meaning to write a post discussing that, but I found that someone else had already written a very nice discussion on that very topic. I thought why duplicate the efforts of someone else who has done a fine job already? So instead of writing my own post, I am just going to refer you to their blog post. So without further ado, may I present…
Welcome back! I hope everyone had a great holiday to mark the end of a great year. 2013 marked the inaugural year for Paleoaerie. Version 1 of the website was set up, providing links to a wealth of online resources on fossils, evolution, the challenges of teaching evolution and the techniques to do it well. The blog had 26 posts, in which we reviewed several books and websites, discussed Cambrian rocks in Arkansas and the dinosaur “Arkansaurus,” and went to the annual meeting of the Society of Vertebrate Paleontology. We looked at geologic time and started a series on dinosaur misconceptions. We also had several Forum Fridays, recapping the many news stories reported on the Facebook page. One of the recent things we’ve started is Mystery Monday, posting a fossil of the week for people to try to identify. Speaking of which, to start off the new year, the first mystery fossil will be posted early. look for it at the end of this post.
In the upcoming year, we hope to expand the site, providing many more resources, along with continuing posts on Arkansas geology and fossils, including many more mystery fossils. Stick with us and you will learn about the history of Arkansas in a way that few people know. The site will be revamped to be more user-friendly and enticing to visitors. If plans materialize, we will be adding interactive activities, animations, and videos, many of which will be created by users of the site. Materials from workshops and talks will be posted for people to view and use. More scientists will be posted that have offered their services to teachers and students. We encourage you to contact them. They are there as a resource.
Of course, all of this does not come free. it takes money to provide quality services. Thus, more avenues of funding will be pursued, including other grant opportunities and likely a Kickstarter proposal. You may soon see a small button on the side of the website for Paypal donations. Any money donated will go first towards site maintenance. Other funds will go towards a student award for website design, a 3D laser scanner to put fully interactive 3D fossil images on the site, and materials for review and teacher workshops. If grant funding becomes available, additional money will be spent on research into the effectiveness and reach of the project. But even if no more funding becomes available, you can still look forward to continuing essays on Arkansas fossils, reviews of good books and websites, and curation of online resources suitable for teachers, students, and anyone else interested in learning about the endlessly fascinating history of life on planet earth.
I mentioned at the beginning about the latest mystery fossil. Here’s the first hint: it is a very common fossil found in Arkansas and lived during the Mississippian period roughly 330 million years ago. More hints and photos to come. Leave your guesses in the comments section. Don’t worry about getting it wrong, every success has lots of failures behind it. Errors are only stepping stones to knowledge.
Clue number 2: Many people think I’m a coral, but I’m not.
Clue number 3: I am named after a famous Greek mathematician and inventor.
What am I?
We began the week with our first Mystery Monday for paleoaerie.org with the picture of an interesting Arkansas fossil. Today, Forum Friday will become Fossil Friday as well as we identify the fossil. Did you guess what it was? See if you were right below the picture.
Congratulations go to Allie Valtakis, who correctly identified it as a nautiloid cephalopod. This particular one is Rayonnoceras solidiforme. It has traditionally been placed within the Order Actinocerida, although some workers have placed them into the Order Pseudorthocerida, which is known for their resemblance to the more commonly recognized orthocerid cephalopods.
What are cephalopods, much less nautiloid cephalopods, you ask? Cephalopods are the group of molluscs that include squids, octopuses, and cuttlefish. There are three major groups: Coleoidia, which includes almost all the modern cephalopods; Ammonoidea, which includes almost all the extinct ones and are known for their complexly sutured shells; and the Nautiloidea, which are mostly extinct, the only living form is the Nautilus. The ammonoids and the nautiloids both formed shells. What differs between them is how they made them. Some of those in Coleoidia also form shells, but they have been greatly reduced and internalized, such as in squids, or lost altogether, such as octopuses. For those with external shells, they have the problem that shells don’t get bigger once the mineral is laid down, so they quickly grow out of their shells. They solve this by adding mineral to the front of the opening in an ever-increasing funnel, periodically walling off the back of the living chamber (leaving a small opening for the siphuncle that goes all the way through the shell, creating a series of gradually increasing sections.
The ammonoids are well known in the fossil record, particularly the subgroup called ammonites, having a diverse array of straight, curved, and coiled shells. What makes them unique from the nautiloids is the sutures between sections are wavy, sometimes showing astoundingly complicated patterns. The nautiloids, on the other hand, sport very simple, smooth curves. It is this group in which Rayonnoceras belongs.
Rayonnoceras lived about 325 million years ago in the Mississipian Period, although nautiloids as a group have been around since the Cambrian Period over 500 million years ago. What makes this particular species so interesting to Arkansans is that the largest nautiloid cephalopod ever found was discovered near Fayetteville, AR. It was 2.4 m (8 feet) and found in a rock unit named, appropriately enough, the Fayetteville Shale, a unit of dark gray to black shale and limestone, indicative of a warm, shallow marine environment without a lot of sediment input, much like many areas within the Bahamas today.
To recap what we’ve covered over on the Facebook page, we recommended a book discussing misunderstandings in human evolution and another in how evolution affects our health. We saw a hominid fossil hand bone that helped to show how we differed from australopithecines and genetics work that showed us how we didn’t differ from Neanderthals.
We read about genetics work that informed us how flowering plants evolved by doubling their own genes and stealing genomes from other plants. We learned about a “second code” within DNA and why the hype was bigger than the story, but may help us rethink our DNA analogies.
We saw how birds defend themselves against cheaters and learned the first lizards and snakes may have given live birth. We also got some information on how teaching and testing will need to change under the Next Generation Science Standards.
On a final note, this will be the last post this year on paleoaerie.org. Enjoy the holidays and join us in January, when we will be embarking on discussion of the Ordovician rocks and fossils in Arkansas. Over the spring, we plan on discussing several vertebrate fossils found in the state. There are several books and online resource reviews coming up as well. We will be adding to our Scientists in the Classroom and adding several new resources to the links pages. As always, we will be posting a plethora of current news items on Facebook, so stay tuned! In the meantime, tell us what you liked, didn’t like, want to see more of, and any questions you may have.
Likely thanks to upgrading computer systems and the joys of trying to figure out new setups and operating systems, there seems to have been a small glitch deleting the post that was supposed to go up Friday, so it is getting posted today. So let’s see if we can make lemonade from the lemon.
On Facebook, I started a new set of posts, in which I post a picture of a fossil found in or could be found in Arkansas and see if anyone can identify it. The first one I put up was of a mosasaur, a huge aquatic reptile that swam around Arkansas seas during the Cretaceous Period. People seemed to enjoy it, so I will be doing this on a regular basis. However, it has come to my attention that many places block Facebook, including a lot of schools. So I will be posting them on the blog. I will try to post a new picture every Monday and will then provide the answer on Friday, giving people the week to see if they can come up with the answer. Don’t worry about being wrong, we learn more from our failures than our successes anyway. You can’t win if you don’t play. So with that, let’s play! here is today’s pic. Can you tell me what it is?
In the meantime, if you missed out on all the stuff we covered on Facebook, here is a brief summary of most of hte stories.
Of the many new fossils and work on fossils that were reported on this month, we saw a new fossil primate that may have been ancestral to lemurs and lorises and giant, terrestrial pterosaurs of doom. We learned about the earliest flowering plant in north America, new crests for old dinosaurs and the promise and perils of resurrecting dinosaurs and other extinct animals..We learned about some amazing animals, from snakes that shrink their own heart and intestines between meals (and the genetic switches that allow them to do it), to animals with no stomachs. We learned about tool-using crocodiles and flower-mimicking insect predators. We learned that unidirectional breathing occurs in lizards as well as crocodiles and birds and why dinosaurs developed beaks.
We learned about evolutionary ghosts, how animals colonize new territory, and how unmasking latent variation within a population can lead to rapid evolution.We learned about the end-Cretaceous extinction and how the Siberian Traps caused the largest extinction event of all time.
We learned how evolution made it easier for people to believe in God than accept evolution and why fanaticism of any stripe can lead one astray. We read a discussion about the importance of scientists in science communication, and why we shouldn’t ignore Youtube. We found help in teaching controversial subjects in hostile environments and apps to help teach hard-to-grasp subjects like astronomical distance.
We learned about how bacteria avoid the immune system to cause disease, how they form an important part of breast milk, and the four billion year history of vitamins. We learned even bacteria have a hard time living deep inside the earth and how viruses can kill even antibiotic-resistant bacteria. We also read a review of a book on evolutionary medicine.Genetics work played a big role in the above stories, but it also gave us the discovery of a second code within DNA and more support for comb jellies being the first animals. We learned why protein incompatibilities make hybrids sterile and how early hominids interbred to form modern humans.
So, what were the stories you liked? Did it spark any thoughts, either good or bad? Was there anything that you saw that we didn’t mention? Share your thoughts and don’t forget to try your luck with identifying today’s Arkansas fossil!