STL Science Center

STL Science Center

28 February 2017

Books on Parakeets

The definitive guide to the Carolina parakeet, Conuropsis carolinensis, is most likely one of the many books that have been written about the extinct bird. There are scholarly articles as well but the books have done a great job of discussing and describing everything about the bird, its life history, and its habitat. The newest book is a 2004 Snyder book called The Carolina Parakeet: Glimpses of a vanished bird. The book is comprehensive and well worth the cover price. Articles worth reading include the Kirchman, et al. 2012 phylogenetic relationship paper describing the familial relationships of Conuropsis. Because I live in Missouri I find the McKinley papers of the 1960's (The Carolina Parakeet in the upper Missouri and Mississippi river valleys and The Carolina parakeet in pioneer Missouri)to be quite intriguing. There are a number of similar papers for different regions times in history describing the world of the Carolina parakeet.

27 February 2017

Single Documentary

As stated yesterday, there is a sad lack of Carolina parakeet material online. There is only a single documentary available online (and I cannot think of any I have seen on television) that discusses Conuropsis, its life history, and its disappearance from the wilds. The 5 minute short looks to be a little bit older, but its quality is acceptable. The scientific quality of the information is also acceptable. Rather than continuing to go on about it, we ought to just watch it, because it was the only thing online to watch this week.

26 February 2017

Recently Lost, Quietly Remembered

There are not a lot of sources for the Carolina parakeet. This is perplexing and a little sad given that the Carolina parakeet was determined to be extinct less than a century ago. It is also alarming that an animal as beautiful as the Carolina parakeet could be both the only parrot and a beautiful bird of North America and be largely unknown less than a century later. Extinct animal websites have not forgotten Conuropsis as we can rely on websites like About to bring us facts that are easily readable by most readers online. A slightly higher reading level can be found on the site ExtinctAnimals. The site New Dinosaurs sits comfortably between the two in terms of reading ability and adds in a significant number of illustrations of the bird from a diverse group of artists.

25 February 2017

A Subfossil Week

©John James Audubon
On infrequent occasions in the past this blog has focused on animals that are technically labeled as "subfossil" meaning that the animals are recently extinct and are known from remains that have not been buried long enough to undergo fossilization. This week is dedicated to one such animal, a small bird from north America known scientifically as Conuropsis carolinensis Linnaeus 1753. Colloquially known as the Carolina parakeet, this small colorful bird was deemed extinct in the wild as late as 1939 with the last breeding animals dying in the Cincinnati Zoo in 1918; eight years after the last known wild sightings of one of the birds. Once known to range from New England to Colorado and south to the Gulf of Mexico, the Carolina parakeet was the most northern ranging parrot and the only parrot native to North America outside of Central America. As with many parrots, the Carolina parakeet was a victim of the pet industry and its feathers were used for fashionable hats. Additionally, hunting and grazing controls were employed against the flocking bird with no real regulation, allowing for mass hunting like that which caused the extinction of animals like the Passenger pigeon. A great loss for the wilds of North America, the Carolina parakeet is very recently extinct, but little is actually known about the birds, as we will see throughout the week.

24 February 2017

Scenes of A River

Some of the best scenes are murals and I thoroughly enjoy the immense extended scenes that murals present to the viewers. Today's artistic interpretation of Stupendemys appears as a character in an elaborately detailed mural-like piece. Clearly this image comes from a book, but would work as a mural (also calling this a two page spread is less flattering than calling it a mural). The Miocene flora and fauna around Stupendemys are all of an older style. The art itself and the coloring also betray the age of this piece; there is no attribution accompanying this image online. Regardless of its age, the scene is well presented if not fanciful, considering the massive amount of animals at the river's edge. The waterway shows a considerable number of the animals we know lived with Stupendemys as well, something not seen outside of mural style illustrations of an animal and its environment.

23 February 2017

Popularly Stupendous

Stupendemys is the largest turtle that ever lived, as far as we know as yet. This has not gone entirely unnoticed by fossil animal enthusiasts, paleontologists (professional or amateur), or by the general public. However, the sources for popular culture references are still somewhat on the shallow end of the pool for this amazingly large turtle. The only film reference to the giant turtle is from the straight to video Land Before Time V; I try to not acknowledge that there are movies beyond the original, but they serve as introductory videos to dinosaurs for some very young folks and that I am okay with. Probably one of the best places online to get information from a more amateur paleontologist sort of voice is this 2012 Lord Geekington (Cameron McCormick) blog post. Posting about a blog post in a blog post is a little strange, but given the lack of books and most other pop culture references, it seems a fitting way to end the post.

22 February 2017

Turtle Anatomy

As mentioned yesterday, there are two major divisions of turtles aside from binning the animals as freshwater, marine, or tortoise. There are other aspects of the anatomy of Stupendemys that are just as important as the way which it retracted its neck and head. Most of the anatomy that has been described is related to the shell of the turtle as the enormous shell was most readily preserved and fossilized. Additionally, materials such as the humerus, pelvic girdles, and an incomplete set of vertebral elements have been found and described. The "problem" with this turtle is that its anatomy is not that much different from modern turtles as to point out anything exciting or overwhelmingly primitive about Stupendemys. The turtle is remarkably enormous though, with the humeri measuring 310 cm and 340 cm in S. souzai and S. geographicus respectively.
Photo by Ryan Somma at American Museum of Natural History. CC BY-SA 2.0

21 February 2017

Types of Turtles

There are two types of turtles in this world, marine and freshwater notwithstanding: pleurodira and cryptodira. Pleurodiran turtles retract their heads into their shells by bending their necks in the axial lpane whereas cryptodiran turtles lower their necks and retract their heads into their shells. The majority of living turtles are cryptodiran turtles, but there are notable groups of pleurodirans as well. Stupendemys is one such notable member of the pleurodira. the anatomy of this system of hiding its head has been described in many papers, notably in Scheyer and Sanchez-Villagra 2007 and the slightly older de Broin, et al. 1993. The initial description of the turtle is not online; however, the description of the second species named, Stupendemys souzai, is available online. This is a good reference for not only the anatomy of the genus, but also general turtle anatomy, as modern knowledge of turtles is used to more accurately describe the fossil by the authors Bocquentin and Melo.

20 February 2017

Big Turtle, Little Star

There is an awful void of popular knowledge about Stupendemys. The name alone, meaning Astonishing Turtle, would seem to require more coverage than the turtle has received on the internet, in documentaries, or in movies and television. The giant turtle is shown some love in the amateur video sphere as more than one fossil enthusiast has dedicated some time to describing the turtle and sharing illustrations and other recreations in their videos. The most informational of these videos was posted by a user from the United Kingdom known as The Sarcastic Raptor who posts videos about games as often as videos about extinct animals. Enjoy his description and the images he has found for his video below.

19 February 2017

Fresh Prince of Turtles

Freshwater turtles are capable of growing to large sizes in some genera if allowed to continue to growing for along time and not killed at young ages. The past is littered with the remains of giant turtles, both freshwater and marine. One of the largest genera of these freshwater turtles was the turtle Stupendemys. Consisting of two acknowledges species (S. geographicus Wood 1976 and S. souzai Bocquentin & Melo, 2006), Stupendemys carapaces averaged 1.80 m (5.9 ft) long with the largest individual approaching an estimated 3.3 m (11 ft) long carapace; an estimate that makes this turtle larger than the largest marine turtle Archelon. These two species are of similar size with S. souzai being described as smaller and have both been recovered from South America; S. geographicus from Venezuela and S. souzai from Brazil. Thought to be an enormous grazer and terrible swimmer, it has been hypothesized that Stupendemys used its weight to control its buoyancy and keep it grounded in the vegetation of the calm slow moving riverbeds it would have inhabited. There are hypotheses that the habitat of the turtle may have lacked significant predators, allowing the animal to reach the sizes that it did, but regardless of the validity of these hypotheses, this was an enormous turtle as we can see below with this replica carapace:
Unattributed photo found online

18 February 2017

Giants of the Lost World

Donald Prothero has taught multiple generations of paleontologists, biologists, and science enthusiasts in his 35 year career. He has written more papers and books than I can count and I, along with many others in the field, have read a great deal of his work over the years and know his contributions to the field quite well. I was recently offered the opportunity to read and review his latest book, Giants of the Lost World: Dinosaurs and Other Extinct Monsters of South America (Smithsonian Books, 2016) and I am quite honored to share my impressions of the book with all of you here today.

I am a big fan of art and figures in scientific books and so the first thing that I do with any book is check out the cover and thumb through the illustrations. This book, from the artistic standpoint, does not disappoint the modern reader. Images are clearly captioned and placed in appropriate places in coordination with the narration of the book. Photographs, reconstructions, and supporting graphics (phylogenetic trees, maps, etc.) are all black and white, save 16 color plates which also include computer generated models of some taxa. These illustrations are high quality, modern scientific interpretations of extinct animals which, for readers that enjoy visuals when they read scientific books, enhance the reader's understanding of the worlds that are being discussed in this book. What's more, the book's sources for illustrations are taken, often, from the internet; an innovative approach to sourcing illustrations.

I say worlds in reference to the illustrations rather than "the world" because the narrative of this book is not simply the history of South America, but the history of the lands that South America bordered, touched, and influenced (or has been influenced by) in terms of both flora and fauna. Additionally, global extinctions are discussed at the global scale, as they should be. The treatments of the debate over the modes and scopes of great extinctions like that at the Cretaceous- Paleogene boundary is intense with details of geology, biology, and physics explained that caused specific events to occur as we know them from the fossil record. The well laid foundation of historical events in the book is key to discussions of the flora and fauna of different eras and this history is very well detailed. The language of the history is scientific, but easy to approach for casual science enthusiasts like many of the readers of this blog. However, seasoned scientists can appreciate the professional language and how it is made accessible to not only scientists but also the general public in a manner that is professional and respectful.

The treatment of the animals in this books is likewise respectful and equal across taxa. A paleontologist focusing on fossil rhinoceroses and other mammals for a great portion of his career, one might expect Donald Prothero to be extremely biased toward the mammals that he discusses in the book. It is true that a good portion of the book does discuss mammals, their rise to dominance over the landscape, and the many different stages of their evolution; however, reptiles, dinosaurs, and birds receive considerable attention as well and there are even mentions of amphibians and marine life.

This book is written for a popular audience and discusses and describes extremely high level concepts in a manner that is accessible, fun, and well illustrated. The work is educational but entertaining such that it is an easy read. The chapters can be read as stand alone units but together represent a rich history of a continent, its animals and plants, and the world in which it is a part. This is a book that should be read by professional and casual paleontologists that love mammals, reptiles, birds, and the overall pursuit of more knowledge.

17 February 2017

Life Sized Models

A model of Nqwebasaurus existing somewhere in the world is inevitable. The fact that it is in South Africa should be of very little surprise given that the fossils were discovered there. This model pre-dates the knowledge of the ubiquity of feathers and as such is quite a basic scaly dinosaur, but feathers in theropods this basal have not been ruled out as entirely possible as yet. The anatomy described in the papers we read this week is evident in this model. The digits of the manus appear to be quite exaggerated; however, in looking at the fossil we can see that the digits are fairly elongated. Impressively, the opposable digit is very well modeled here, making the forelimb look that much more terrifying. Possessing feathers or not possessing them, the models and illustrations we have seen this week of Nqwebasaurus are all equally interesting and make this basal coelurosaurian look quite dynamic.
Photo by William De Klerk

16 February 2017

Famous Tongue Click

Nqwebasaurus is the only dinosaur with a name that includes a tongue click. It is also the only basal coelurosaurian from South Africa and one of the earliest theropods found in the entirety of the continent. These two reasons for popularity have fueled inquiry and interest in Nqwebasaurus but its name is difficult to say and spell, which has stalled some of the general popularity that the dinosaur has been subjected to or affected by (depending on your stance). The strange general popularity lack for this dinosaur even makes the illustrations of the dinosaur somewhat rare. There are interesting facts that are less well known about the dinosaur that could make it even more interesting or popular with the general (non-scientist) populace. One of these is the lesser stressed identification of possible gastroliths in the abdomen of the dinosaur, pointing to an herbivorous diet. Gastroliths are stones that are smoothed by mechanical manipulation in a muscular organ such as a gizzard or crop. These stones are used to grind tough fibrous foods so that an animal does not need to chew and rechew and chew its food again to break down the strong vegetation to get at the nutrients contained within.

15 February 2017

Opposable Thumbs

If one remembers the cartoon that was shared on Sunday there was mention of opposed digits and climbing abilities prescribed to Nqwebasaurus. There was not much embellishment in those statements; there is always some in developing hypotheses. The forelimb and hand of Nqwebasaurus are unique in that they do appear to have been well-adapted to not only climbing, but also partial opposition of the digits allowing for a certain amount of grasping. This amount of grasping has not been quantified, though the partial nature of the opposition has been stressed in the initial description and subsequent publications. When looking at the fossil it is not difficult to understand why the degree of movement of the manus and its digit's movements is not entirely explored, modeled, or simply known at this time:

14 February 2017

The Literate Dinosaur

Nqwebasaurus is well read and well read about. Not many basal coelurosaurs have been found and of those that have, only one comes from South Africa. Officially an ornithomimosaur, Nqwebasaurus has been discussed in theropod, coelurosaurian, and ornithimimid contexts since its discovery and description in 2000. The paper announcing that discovery is a paper worth reading and the author list is little bit like an all star lineup for paleontology. The paper appeared in the Journal of Vertebrate Paleontology and is authored by De Klerk, Forster, Sampson, Chinsamy, and Ross (if you are a more casual reader these names are less impressive than if you are familiar with their work, but it is impressive, I promise). There has been extensive examination of the fossils and subsequent discoveries since the initial description such as a description of a second set of remains in 2009 by Forster, et al. that compares these remains with those of the holotype of Nqwebasaurus. They determine that these belong to a second theropod inhabiting the same area, which is equally intriguing despite not representing another individual of Nqwebasaurus. Placing animals outside of Nqwebasaurus is not the only thing that has been done to the genus since its description though. In 2012 Choiniere, et al. re-examined the holotype material and further excavated the matrix of the fossil. They found more material and were able to better describe Nqwebasaurus which included a more complete and more soundly supported phylogenetic assignment to the position we now know for Nqwebasaurus. This paper is so far the most important description or redescription of the animal and its place in the family tree.

12 February 2017

Morning of the Nqwebasaurus

Cartoons used to be a normal way to start weekend mornings and those of us old enough to remember certainly miss them. Kids that love dinosaurs should start today with a cartoon featuring a talking Nqwebasaurus. While watching this short, they can read the facts presented on Prehistoric Wildlife or a more abbreviated version on Enchanted Learning. Adults can enjoy these also, of course.

11 February 2017

Early Bird Mimics

There are a lot of dinosaur names that are hard to pronounce or spell and one of the absolute most difficult is the basal ornithomimosaur Nqwebasaurus thwazi. Recovered from South Africa's Kirkwood Formation of the Early Jurassic-Late Cretaceous, Nqwebasaurus is named after the formation itself, which is called Nqweba in Xhosa, the local group of Bantu people living nearest the formation where the skeleton was recovered from. As the earliest coelurosaur of Gondwana, it is remarkable in many ways despite looking somewhat plain:
©IJReid

10 February 2017

Pretty Whales

Basilosaurus is a favorite for reconstructions as well as re-creations and interpretations in paleoart (there is currently a lot of talk about the differences on Twitter). There are many different illustrations of Basilosaurus that have many different body types and rather than discuss the merit of one over another today, I feel that is is much more productive to instead share a few and let the readers come to their own conclusions on what is the most whale-like interpretation or the least, or even the most interesting regardless of its whale-like attributes. Please enjoy these interpretations of Basilosaurus and later today I will post about the new animal for this week. Additionally, I am in the process of finishing up a book that will be my pleasure to introduce and briefly discuss with everyone.
© Pavel.Riha.CB CC BY-SA 3.0

Unattributed

©Nobu Tamura CC BY-SA 3.0

09 February 2017

Popular Whales

The most common avenue for popularity for any fossil animal outside of documentaries in current society is through video games. The hopes and dreams of many scientifically minded folks always want the number one area to be the museum but with so much electronic distribution of information these days the museum has fallen behind slightly but knowledge about animals. Curiosity generated through any venue or modality is extremely important in moving the research, future knowledge, and continued popularity of fossil animals higher in the public and scientific conscience. Seeing Basilosaurus featuring prominently in video games is somewhat intriguing to me. Its portrayal in Ark: Survival Evolved is as a highly detailed creature that lives within the underwater portion of this game's world. There are a number of videos for the whale, but this one made by Alexis Arcade, despite some interesting pronunciations is directed with vigor and excitement, and that is all I really ask for as long as the information, which in this case is that which is provided by the game creators, is accurately relayed to our audience. Anyone interested in a very long video with the animal swimming, fighting, and eating in game should check out Jimbob Soss' video here (38:00 is where the Basilosaurus comes into the video).

07 February 2017

Stereotypical Papers

One of the most highly anticipated discoveries in the whale research is the purpose of vestigial hindlimbs and, heavily coinciding with that topic, when the hindlimbs became entirely vestigial. I bring this up because two and a half (one paper being a description of the entire skeleton and mentioning the limbs and lack thereof) of the first five papers that appear in a standard search for Basilosaurus are concerned with the pelvic girdle an the hindlimbs. The evidence of hindlimbs and feet, discussions on the pelvic girdle (hips) themselves, and a treatise on the jaws and "other parts" figure prominently in Basilosaurus research. As an early whale this is not only expected, but also somewhat unimpressive, given that it is expected. The finds themselves are impressive and tell us a lot about the evolution of whales and what makes a whale a whale. Those of the readers interested in the teeth and biting of Basilosaurus are not left out, there is a wonderful paper on bite marks and the forces associated with Basilosaurus bites in a Dorudon (another type of whale) that is available online to read. This paper includes very clear photographs of Dorudon fossils as well as some nice reconstructions of the wounding action.

06 February 2017

Movie Whales

It turns out there are quite a few resources for Basilosaurus in the film and movie department. The most famous is the one we are going to watch, but the others will be around for other days in the future, like Thursday when we talk about popular culture references. This is only a small clip from the show, but it is worth finding the whole episode if one can find it.

05 February 2017

Belated Facts

Because I was a little slow this weekend (I was doing a lot of reading mixed with a lot of not being online and hanging out with my wife) I am posting the facts about Basilosaurus on a Monday morning. There are many websites and a number of videos that share facts about Basilosaurus because it is an animal of interest to many people, scientists and non-scientists alike. Websites include About, Prehistoric Wildlife, and even the BBC, just to name a few prominent sites that list facts and discuss this early whale. Since it is Monday and possibly more hectic than a normal day, the videos playing in the background may be easier to get facts from for some today. There are a number of fact presenting videos, but the two below summarizes and discuss the popular knowledge about Basilosaurus equally well:

04 February 2017

Angry Whales

The earliest whales walked the shorelines of swamps and oceans. The earliest large fully aquatic whales that we know of and would recognize as whales were still rather alien appearing in terms of what we think of as whales; however, their largest representatives could be mistaken for nothing else due to their size and mammalian characteristics. The king of these early whales, by name the "king lizard", was Basilosaurus. Consisting of two recognized species, B. cetoides and B. isis, Basilosaurus was a predatory whale measuring up to 18 m (59 ft) long and possessing a skull and feeding apparatus capable of an estimated 20,000 pounds per square inch of force during an extreme bite. Flippers extending 35 cm (14 in) stabilized the whale as it propelled itself through the water with a hypothesized undersized, by modern standards, fluke capable vertical movements possessing either a dorsal fin or ridge along the midline of the tail. This structure is hypothesized currently and its exact size and morphology are unknown presently, though support for both morphologies have been published in the past.
Basilosaurus on display in the Life in the Ancient Seas exhibit, 1989. Photo by Chip Clark, Smithsonian Institution

03 February 2017

Skinny or Beefy Neck

© Øyvind M. Padron
The neck of Piatnitzkysaurus is of the least concern to most researchers and illustrators. However, in searching for impressive artistic interpretations today I noticed that there was an interesting range of neck morphologies depicted for this dinosaur. Ranging from extremely gracile and snake-like to highly muscular and robust, the illustrations of the neck in Piatnitzkysaurus set the tone for the remainder of the illustration. A dinosaur with a gracile neck is most often portrayed as possessing a gracile frame, hindlimbs, tail, and forelimbs. Typically these smaller necks also have lighter heads resting at their rostral ends; a giant beefy head would be difficult or impossible to support on a gracile neck. Conversely, dinosaur illustrations with extremely large necks tend to have robust and muscular bodies and heads to realistically portray proportional animals. The difference between gracile and robust is not just the overall look of the animal that is reproduced of course. Predatory dinosaurs with smaller heads and more streamlined bodies are most often portrayed as speedy smaller animals capable of stealing eggs and chasing down faster prey items. These tend to influence the dinosaur movie chase scenes that involve acrobatics and high speed escapes. Robust heads and bodies that appear stronger are more common with dinosaurs that break through walls or crush cars in movies in order to get at their prey. Hollywood, in this respect, is not entirely incorrect; nor should they be considering that paleontologists have been consulting for these kinds of movies for a long time. The difference between robust and gracile versions of Piatnitzkysaurus has not been settled and interpretations on both ends of the range are still produced. The anatomically correct version of the animal is somewhere between the two, though examples of both probably existed within the variation of the animal in its history as a genus and neither should be entirely discounted without definitive proof of a body size.
©Rodrigo Henrique Gomes

01 February 2017

Long Drawn Out Dig

The holotype remains of Piatnitzkysaurus took multiple years to fully excavate from the Patagonian rocks. Dated from approximately 166 to 164 million years ago, the Callovian rocks of the Jurassic were excavated in 1977, 1982, and 1983 to remove the entire holotype specimen. The general resemblance of this dinosaur to Allosaurus was first noted by Michael Benton upon surveying the strong arms and legs of the predatory dinosaur. Many of the illustrations are very much inspired by this resemblance in addition to the actual anatomy of Piatnitzkysaurus, as can be seen here.
©Nobu Tamura