Scholarly Fun

Yunnanosaurus has been written about extensively. The most important papers are the papers that describe various aspects of the fragmentary prosauropod. There are fewer articles exploring aspects of functional morphology and other aspects of paleobiology, but we can ignore this lack for the most part as the descriptions more than keep us occupied in terms of pages for reading and pure content. Young's original description is online but can be difficult to access. In contrast Sekiya's description of a new species, Y. robustus, is easier to access and read online. Those interested in just the skull may, instead, find Barrett's description of the skull of Y. huangi more useful. Be aware that this paper is entirely a description of the skull and not a biomechanical analysis of the skull.

Popular Without Movies

Yunnanosaurus is an early dinosaur with no movie credits in its accomplishments. There is a WizScience video that exists regarding Yunnanosaurus. Unfortunately the other videos mentioning the dinosaur either do not actually show the animal or have a very abbreviated (think 2 - 5 seconds) of actual mention in the videos. This is a short video, but one can add on this how to draw video as well to get more Yunnanosaurus today:

Long Lists of Knowledge

Yunnanosaurus is a well known sauropodomorph and as such has many fact pages devoted to it hosted online. These include well known sources such as KidsDinos and Prehistoric Wildlife. It also includes sources we have not referenced often including Age of Dinosaurs and a Raresource page. For the first time in a very long time we can also share a coloring sheet of Yunnanosaurus (that may actually be almost accurate). Enjoy reading facts and coloring your own Yunnanosaurus this evening!

Silly Sauropodomorphs of Space

This is the last week of November and therefore it is the week of the calendar creature. This month that animal is the sauropodomorph Yunnanosaurus. Discovered originally in the southwestern Chinese province of Yunnan and described in 1942 by C. C. Young (the anglicized name of Chinese paleontologist Yang Zhongjian). The original fossil material consisted of twenty incomplete skeletons of the facultatively bipedal sauropodomorph dinosaur. Two species are recognized: Y. huangi Young 1942, and Y. youngi Lu, et al. 2007. The teeth of Yunnanosaurus may be the dinosaur's most interesting feature, as we shall see later in the week; however, its position early in dinosaur evolution is also interesting and we may learn a lot about early dinosaur environments from studying this animal over the week.

Quality Images

The best quality images of Shastasaurus are all somewhat similar and lack the flash that is often added into dinosaur illustrations. However, there are a number of high-quality illustrations of Shastasaurus that are interesting and intriguing. One such illustration shows Shastasaurus digging along the bottom of the ocean for its food, presumably. This is one of the only (if not the only) image of this ichthyosaur from a more ventral angle. The belly of the beast, figuratively and literally, is not all that impressive. The flippers and underside of the trunk are smooth and non-remarkable; however, the tail is differently interesting (that does sound odd, admittedly). The tail vertebrae, assuming that this illustration is entirely accurate, occupy the ventral region of the tail and curve downward to the end of the hypocercal tail. The tail also has what appears to be an untethered membrane which, being untethered to the body or the remainder of the tail, would need to be extremely rigid in order to produce any appreciable thrust. Either way, adding the membrane to the tail is not unique to this illustration, but this version of the animal has probably the most conservative amount of interpreted soft tissue that has been shown.

©Nikolay Zverkov

Ancient Marine Books

Shastasaurus has been featured in a number of books concerning and written about marine reptiles of the Mesozoic. As noted earlier in the week Shastasaurus appears in a limited number of tribute videos as well. A number of popular articles have come and gone, particularly in recent years, pertaining to the diet of Shastasaurus. These articles mention specifically the hypothesis that the toothless snout of Shastasaurus was ideally suited to suction feeding and ingesting cephalopods specifically. However, the mandible and jaw joints of Shastasaurus were not adapted to accommodate the range of motion required for successful suction feeding. Shastasaurus most likely required massive numbers of cephalopods with or without the ability to suction feed given its size. One of the key abilities of Shastasaurus in ingesting massive numbers of animals like this would be to get into a position to be able to eat them. Its large size and hypocercal tail probably made Shastasaurus basically incapable of high speed swimming. However, migrations of smaller taxa or simply larger, slower swimming taxa, may have been on the menu for this large mostly lumbering predator of the Triassic. Clearly it must have been successful at one time or another or it would not have survived long enough to make it into the fossil record. Conversely, Shastasaurus may have swam slowly through large groups of fish, or circled them like large whales sometimes do today to funnel them into an area fit for gulping.

This is highly speculative and not entirely taken from any of the sources discussed on Tuesday; take this conversation on diet with a grain of salt, that is to say. Hypothetical situations are fun to discuss, but definitely be aware that there are scientists that make a living studying Shastasaurus that know more about its diet and the evidence for and against specific hypotheses that have been discussed here today.

©Nikolay Zverko

Behold the Mountain

I have referenced mountains a number of times when discussing Shastasaurus this week and that is not without purpose. Shastasaurus was, after all, named for Mount Shasta in California. Shasta is an active volcano in the Cascade Range and is absolutely enormous. The ichthyosaur is as well. Many large marine animals comparable to Shastasaurus are of similar morphology. The most notable character of this morphology is actually the lack of a character: the dorsal fin often shown in recreations of later ichthyosaurs is entirely lacking in Shastasaurus. Other morphological characters of Shastasaurus are expected, such as a hypocercal vertical tail and pelvic and pectoral fins. The skull of Shastasaurus is not completely known, and as such the cranial form is not entirely known either. Therefore the only characters we can discuss for certain are the tail and dorsal fin and the breadth of the ribcage of Shastasaurus. The ribcage is short and shallow, giving Shastasaurus a slender body profile. The toothless snout (mentioned before), slender profile, basal tail, and lack of dorsal fin show Shastasaurus to be a basic and primitive ichthyosaur. The size of the animal is interesting, however, as it is enormous and exceptionally long (up to 21 meters estimated) despite its shallow ribcage (approximately 2 meters deep by 7 meters long) and primitive features.

A Day of Papers

Shastasaurus is a complex animal and because of the complexities associated with this giant marine reptile there have been a lot of different studies, descriptions, and research delving into the life, anatomy, and phylogeny of Shastasaurus. There are key papers that are more important than others, as is usually the case, that possess more information critical to better understanding of extinct taxa. In this case there are two papers describing potential (and debatable) species of Shastasaurus. These two species are from New Mexico and British Columbia respectively. New Mexico's species, S. altispinus is from the Upper Triassic and was described in 1989. The species from British Columbia, S. neoscapularis, was touted as the exemplar of the genus in 1994. However, since that time the five-plus species have been reassigned, redescribed, and only one sure species now exists (plus two still debated species: S. liangae of China and S. sikanniensis once known as Shonisaurus). A discussion of the implications of S. liangae's short snout and its placement in Shastasaurus was published in 2011. The only quality description of S. sikanniensis was penned under the name Shonisaurus sikanniensis; the animal was reassigned in the previous article about S. liangae and its short snout.

Monday Videos

As promised, here are the videos for Shastasaurus. These are tribute videos, however, they are here for your perusal and viewing pleasure.

Facts and Swimming Mountains

A full size Shastasaurus would be a sight to behold in today's waters. Appearing very piscine (fish-like if you prefer) with its vertically oriented tail but entirely lacking dorsal and anal fins. Approximately the size of a modern blue whale, this marine reptile has managed to capture a fascinated, though small, audience in its considerable wake. The fact that a lot of people know about this animal make it somewhat popular online. This popularity leads to more than a few websites hosting facts about the giant marine reptile such as About, a new-to-us site called Dinosaur Facts, and Prehistoric Wildlife. I plan to save the tribute videos for tomorrow, and there are quite a few of them to share, which means tomorrow will have a lot of images and videos.

Mountainous Ichthyosaur

Shastasaurus pacificus is the only certain species of the genus of mid Triassic ichthyosaurs. The middle Triassic is early in ichthyosaur evolution and Shastasaurus is clearly not as advanced as the more well known Cretaceous ichthyosaurs. However, the Triassic was a pivotal time for these early ichthyosaurs that led to the later Cretaceous ichthyosaurs and Shastasaurus was major player in the evolution of this family. Lacking a dorsal fin and more slender than many later members of its family, Shastasaurus possessed a significantly different shape than the later and more familiar marine lizards.

©Dmitry Bogdanov

Drawing in the Bat

Having a lack of popular references there was no reason to talk about them yesterday. Instead, we come back today to look one of the only well illustrated restorations of this prehistoric bat. The majority of illustrations refer to modern bats to illustrate their interpretations of these older bats. Only one set of illustrations appears to draw its inspiration directly from the skull. The shape of the illustrated heads are what gives away this inspiration of course, with the properly drawn animals possessing a more elongate head than modern bats; the poorly drawn Icaronycteris pieces have a shortened bat face with large flat noses. The ears of either version are open to even more interpretation, but it appears that almost all of these have been illustrated as typical bat ears. This makes sense, though, given that Icaronycteris is hypothesized to have been capable of echolocation. The tail, however, is longer than the legs in the fossil and all of the interpretations.

Your Average Sized Bat

Measuring in at approximately 14 cm (5.5 in) long from nose to tail Icaronycteris was just a little larger than the Little Brown Bat (Myotis lucifugus), the most common bat in North America. The wingspan of Icaronycteris 37 cm (15 in) is one and a half times the span of M. lucifugus. However impressive that sounds, we have to realize that Icaronycteris is still a rather small animal and most likely weighed around what M. lucifugus does (up to 14 grams) and that makes it a relatively small mammal, and a small bat specifically.

Paper Thin Fossil

The American Museum of Natural History holds records for the two most definitive articles written on Icaronycteris. The first article, Simmons and Geisler 1998, describes the familial relationships of the bat, its history, and basically every behavioral and ontogenetic piece of information that has been suggested, tested, and hypothesized about Icaronycteris and Eocene bat populations in general. This tome of information draws from all previous works on the bat and new hypotheses, phylogenetic character descriptions, and their results as interpreted by Simmons and Geisler. An earlier paper that is referenced by the first paper and is also prominent in describing this bat is Novacek's 1987 paper on the auditory capabilities of Eocene bats including Icaronycteris. This paper is shorter, but describes the hearing functionality of what may have been some of the first echolocating flying mammals; adaptations that highly influenced how and why bats behave the way they behave as we know them.

The Single Video

Whenever we have a little known animal we have few if any videos. Icaronycteris is one of those animals that has very few videos associated with it. The videos that do exist are patchy, but there is a link that calls itself a video of an animation and reconstruction of Icaronycteris. However, it calls the fossil bat a "3D Dinosaur" which we know is not at all accurate and is in fact only a stock photo. The lies of the internet sadly. Instead of looking at the non-videos, we should take today to appreciate the fossil itself. The fossil reveals a typical, as we currently think of them today, bat-like mammal. We cannot see the teeth in this view, but we will see later how they are very much like the bats we know today. As stated previously, this bat, despite being very early in the bat lineage, is already very "modern" in terms of its bat-like morphology. The fingers and the teeth are the most outgroup features of Icaronycteris as the teeth are more like those of a shrew and the fingers retain more primitive claws on the first digit. Most notable about the fossil, the tail is longer than those found in modern bats. This is rather evident in the fossil. What is not evident, unfortunately, is the wing pattern of these old bats. We can see later what this membrane may have looked like, but for now we have only the bones themselves.

©Erik Terdal

Short Facts

The fact files for Icaronycteris are lacking almost entirely. The only page hosting a fact file for this fossil bat is About. Eocene mammals are not unpopular really, but fossil bats are very rarely discussed outside of scientific conferences and research discussions. Hopefully after this week that trend will begin to change and more links for fossil bats and more information about them will begin to show up online; That is not the end goal of course but spreading more facts about this small fossil bat would not at all be a bad thing.

True Bat Wings

After a little contemplation it was decided that we should continue our discussion on bat wings, but instead of continuing with small maniraptoran dinosaurs we are going to look at the origin of the phrase bat-like. We described the wings of Yi qi as bat-like and many pterosaurs are described in the same way. However, the origin of the descriptor comes from the small flying mammals that people were most comfortable with (or uncomfortable with). One of the earliest complete bat fossils belongs to an animal known as Icaronycteris. The small microchiropteran, a group of small bats dependent on echolocation, dates from the Eocene and contains three recognized species: Icaronycteris index Jepsen 1966, Icaronycteris menui Russell et al.1973, and Icaronycteris sigei Smith et al. 2007. The type species was originally recovered from the Green River Formation and constitutes the most completely described specimen of the genus. Clearly already a "fully functional" bat, one of the earliest bats was already well adapted for the kind of life that bats still adhere to today.

©Andrew Savedra, Royal Ontario Museum specimen

A Cheeky Image

The images shown this week are all serious reconstructions of the small maniraptoran dinosaur Yi qi. Those reconstructions are all as scientifically accurate as possible with the scientists and artists working together. The majority of the illustrations show the dinosaur in stark high definition with feathering finely illustrated and the sharpness of the image finely tuned for the most realistic habitats possible. John Conway went down a slightly different path in his illustration. This image uses soft colors and a lack of sharpness that captures the dinosaur perfectly while leaving enough of the detail muted that we can interpret some of the fine details for ourselves. Additionally, Conway made his version a little more frumpy looking and a little less angry, as Yi qi tends to look in most other reconstructions.

©John Conway

You Can't Buy Popularity

Yi qi is a popular little dinosaur for a variety of reasons, though that popularity is not entirely evident outside the paleontological community. The announcement of the description was met with typical news outlet fervor, but it died quickly, perhaps even faster than many other new dinosaur announcements. Part of the excitement of the dinosaur is actually the debate that it has caused because of its unique wing structure and the uncertainty of the morphology of that wing. Being toted as a "bat-winged" helped the dinosaur to become a news item and granted it some of the popularity that it has experienced. Its popularity also made many more of its clade members more visible to the public. The name Scansoriopterygidae is still difficult to say but it is more well known now because of Yi qi.

©Matt Martyniuk

What About the Wings

There is something about the forelimbs of Yi qi that seems unnatural or even a bit downright creepy. Yi qi had feathers preserved with its skeleton. Those feathers are stiff and cover almost the entirety of the body. However, there are no flight feathers associated with this dinosaur. Instead, the elongate digits (Digit III being the longest digit) are spanned by a preserved membrane that lacks avian-like feathering altogether. Evidence for this membrane stretching to the torso is not preserved in the fossil, though it has been interpreted as extending that far medially in order to complete a wing structure. The inclusion of a styliform bone, debated as misidentified radius and ulna by some (David Peters for example), was proposed to have expanded the wing caudally from the wrist and past the range of the digits. This gliding wing would have been substantial with this addition but obviously becomes somewhat smaller and less expansive without the added distance from the wrist.

From Xu et al. 2015

Election Dinosaur

Take a moment away from the election in the United States to read this paper describing Yi qi the Jurassic maniraptoran dinosaur. It will make for a pleasing distraction, regardless of who you support, to simply ignore the anxiety and just read some science.

Video-less

Yi qi is very new. Because the little maniraptoran dinosaur is very new it has not had many chances to appear in documentaries or anywhere else. The dinosaur made a few popular news stories and even the short video that we shared yesterday from the publisher of the original description, Nature. There are other short videos, such as this video posted by The Paleo Archive, an account that discusses fossil animals of all kinds on YouTube. Those interested in the take of a young child (seeing young dinosaur fans at work is always fun) can watch this video by Rogie the Dino Boy. His interpretation of the facts associated with this dinosaur are fresh and delivered in the way that only a child could deliver them.

Facts and Coloring Sheets

The video collection WizScience produced a video showing and discussing Yi qi, which is as good a place to start as any in looking for facts. There are other videos to consider as well, such as Nature's short documentary on Yi and its hypothetical flight abilities as described by scientists up to and including research conducted in 2015.

The video from Nature is a companion to the 2015 paper that finally described the 2007 discovery.  The fact files are ultimately all the same as that shown by About, with a little bit of variation speckled throughout the different fact files. The facts are analyzed by a lot of different authors and the interpretations are varied depending on the way that the authors see the data and interpret the reconstructions. Darren Naish, for example, describes the "Dino-dragon" in a different way than it is typically depicted. In the realm of coloring sheets, two black and white drawings could be used for coloring. However, the drawings belong to their artists and are not available for my inclusion here. Therefore, here is a link to different versions of the interpretation of the dinosaur; one by Jaime Headden and the other by Sergio Perez.

Bat-like Theropods

The very small theropod dinosaur Yi qi had unique fingers that separated it from all other theropods along with its sister scansoriopteygids, which were climbing and gliding arboreal maniraptorans of the Jurassic of Asia. A partial skeleton of the animal was described in 2007 and, as of now, remains the only skeletal remains that have been recovered or described of the small dinosaur. Yi qi, like its sister taxa, is assumed to have lived in the trees rather than merely climbing them and gliding down from them. The most unique aspect of the reconstruction of Yi qi is the bat-like patagium that was stretched between the fingers of the dinosaur. We can read the paper later that describes this, but for now, enjoy this Emily Willoughby reconstruction based off of the description:

©Emily Willoughby

Typical Illustrations

The illustrations of hadrosaurs have changed as much and as often as any other subset of dinosaurs over the years since their initial discoveries. Hadrosaurs, however, have arguably changed less than other dinosaurs. The reason for that is not a lack of hadrosaur research or knowledge but rather the general shape of hadrosaurs. Postural changes of the dinosaurs and enhanced precision of soft tissue depictions of the head and neck are the most profound advances in hadrosaur illustration. Beyond these categories, the bodies of hadrosaurs in particular, the depiction of hadrosaurs has remained fairly uniform because there was not a whole lot to change in those areas to begin with. Parasaurolophus and its contemporaries were depicted with bovine bodies because they were basically the cows of the Cretaceous. This explains the bovine appearance of hadrosaurs between the neck and tail quite readily. One other thing that changed in illustrations of Parasaurolophus and other dinosaurs overall that has made a significant impact on the illustrations we see today is the organization of the toes and posture of the feet. Older illustrations feature elphantine feet that end in columns for sauropods and hadrosaurs are not treated much differently in this respect. Some depictions of Parasaurolophus are a little extreme in their depiction of the bovine state of the dinosaurs, such as this image by John Conway (though he is far from the only artist depicting these dinosaurs in this manner).

Parasaurolophus with hypothetical frill attached ©Tom Parker

The Best Paleo Video Ever

The 1980's and early 1990's were filled with some amazing paleontology movies and documentaries. These included images of newly discovered dinosaurs and an immense multitude of hadrosaur models, animations, and recreations. Chief among these is Parasaurolophus and the intriguing anatomy that it possessed. The original attempts at recreating the sounds of Parasaurolophus and many other hadrosaurs were undertaken by a large and varied number of scientists, but the one I remember best was a clip of David Weishampel blowing on plastic piping to create deep resonant sounds. Since that time there have been many other recreations of the sounds using computers and complex algorithms to hit precise notes, such as in this compiled sound clip attributed to Sandia National Laboratories and the New Mexico Museum of Natural History (https://www.youtube.com/watch?v=lBU6zfI1b0U):

These same practices are used to create the Parasaurolophus sounds in popular documentaries such as Dinosaur Discoveries. Did this dinosaur really sound like this? We may never know, but there is a strong amount of evidence that says that Parasaurolophus may have potentially sounded like a living low frequency producing machine. It was probably not capable of defending itself with sound, but that would make for an interesting defense if it was possible.

Parasaurolophus Makes A Good Read

©Brynn Metheney

There are specimens of Parasaurolophus from all over the western half of the continent. There are remains from Utah, New Mexico, and Alberta, Canada as well. Many of the remains of the dinosaur come from Canada, in fact. There are remains described on a regular basis from Dinosaur Provincial Park. A wide variety of topics are discussed as well. These range from ontogeny and heterochrony (life history and developmental change in time and events) in Parasaurolophus to acoustics of the nasal passage, as mentioned yesterday. Parasaurolophus may not have made it into space (contra this Brynn Metheney drawing) but it has indeed created a stellar impression on the history of life and the careers of many biologists and paleontologists.