STL Science Center

STL Science Center

30 April 2013

Discovering Staurikosaurus

Staurikosaurus was named in 1970 and discovered a while before that; 1936 to be exact. Edwin Colbert, the American that named the dinosaur, had the fortune of having the specimen loaned to him for study. His description and comparison with other materials lead to the discovery that this "archosaurian reptile" was one of the earlier dinosaurs of the Triassic. He named his new discovery after the Southern Cross, a constellation, and after the man responsible for the collection of this and many other discoveries in the Brazilian Triassic soils. His initial description of the material is very in depth and contains some nice plates; there is a combination of illustrations and photographs in the paper. Another paper which may warrant attention is a slightly newer paper by D.B. Brinkman and Hans-Dieter Sues. Their paper identifies and describes a Staurikosaurus sp. from Argentina's Ischigualasto formation. They also describe the relationships between Herrarasaurus and Staurikosaurus as sister taxa as well as confirm the placement of Staurikosaurus within the dinosaurs. There are a few other papers out there, but I think these two are good for one day as they are both a bit heavily detailed.

29 April 2013

Fun with Art Snippets

Staurikosaurus, the Triassic dinosaur, is, as we noted, somewhat popular. That has led to a couple "tribute" videos as well as some video game references. As usual, not every single image in the tribute videos that pop up from time to time on the internet are carefully reviewed and are therefore not certainly the dinosaur in question. However, given that a good amount of skeletal material is missing from the discovered remains the illustrated versions of this dinosaur are, as we have seen, highly open to interpretation by the artist in terms of the exact reconstruction of those missing elements of the skeleton. That, then, leads us to these tribute videos that are widely open in their own interpretation of the dinosaur they are showing. There is an amount of fault of the people that create the videos in not finding images of the animal correctly or, worse, accepting every labeled animal they see as an authentic representation of that dinosaur. Some of that incorrectness is always found in these videos, but generally we can look beyond it. Though I know that I have had to edit posts from time to time, it concerns me a little more when these videos are massively incorrect in what they represent because sites like YouTube have such heavy traffic; though we can probably assume that a third of the traffic on the site is directed at a minority of the videos on there. Regardless, it is nice that the video has been posted and has views because it means that someone is interested in Staurikosaurus.

28 April 2013

Staurikosaurus for Kids

Staurikosaurus has links for kids, which is pretty neat for a little understood early dinosaur. Thankfully, the Dinosaurs for Kids site has a nice quality page that is easy for kids to garner information from. Coloring pages are a little bit lacking, but that may have more to do with the fact that Staurikosaurus is still a little known dinosaur. The Dino Directory from the Natural History Museum of London also has a page set up for some facts that are easy for kids to read. Their size chart looks a little bit off, though; the Staurikosaurus is a bit larger than it probably should be.

27 April 2013

The Completed Incomplete Skeleton

Oscar Alcober, Ricardo Martinez; retrieved from Wikipedia
The amount of skeletal material associated with Staurikosaurus actually fluctuates depending on the source, which is quite odd. Usually some sort of consensus of what skeletal element belongs to what animal gets hashed out eventually amongst scientists. Staurikosaurus, however, is, to my knowledge, composed of only the skeletal elements presented in the anatomical drawing shown above. Paul's latest illustration (via the Princeton Field Guide) shows a substantial amount of skeletal material in addition to this material. I saw no mention by Paul or other sources that cite where this material came from, though I have not done a comprehensive literature search for the week as yet so it may be that in a paper I have yet to review this week that the additional material comes to light. Until then, this is the material that was briefly presented yesterday. As can be seen, it is not extensive, though it is a fair proportion of the skeleton and the basal nature of the remains discovered do allow for some assumptions to be made as to the missing elements and their appearance.

©Dmitry Bogdanov
The exact structure of this early dinosaur is a bit "up for grabs" despite the assumptions that can be thrust upon the animal given its basal nature. In a similar image Nobu Tamura illustrates a similar but radically different anatomy for Staurikosaurus. Neither image can be attested to as perfectly correct but they both draw upon the knowledge of the primitive nature of this dinosaur. Dinosaurs of this size were just getting their start in the Triassic and as such were not the apex predators we see in later fossils, but were still quite capable of taking down prey. The manner in which they did so was a little less "dinosaur-like" than when we think of Tyrannosaurs and that sort of large apex predator. Hypothesized to brandish a five fingered hand and foot, these early dinosaurs had small heads and may have had claws that were used more for holding down prey than as killing implements. The Komodo dragon, or maybe even the Green Iguana, may have similar styles of feeding to what Staurikosaurus may have exhibited.
©Nobu Tamura
Both the Komodo dragon and Green Iguana both use their forelegs to hold down food items while pulling with their mouths. Staurikosaurus was bipedal as far as we know though, so does this necessarily make sense? The purported five fingers of Staurikosaurus, a body plan shared with the dragons and iguanas, would have enabled the dinosaur to maximize the flesh it held down as its jaws, which would have had to have been fairly strong, tore pieces of flesh from its victims; there is no knowledge as to whether or not Staurikosaurus was primarily a predator or a scavenger and an herbivorous diet is considered unlikely given the theropod body plan (please keep in mind that Therizinosaurs, though theropods, are considered herbivorous).

26 April 2013

Journeys in the Triassic

We have not been to the Triassic in a good long while, but today we shall venture back there. Herrerasaurids are some of the earliest theropods and, arguably, some of the least understood still. Often this is due to incomplete fossil finds, such as the animal that will be discussed this week. However, a good portion of the post-cranial skeleton of this dinosaur has been recovered in Brazil, of all the places in South America. Typically when we here "dinosaur" and "South America" in the same sentence we typically think of Argentina and Jose Bonaparte. However, Staurikosaurus pricei was named by Edwin Colbert, born in Iowa, and more renowned for having a hand in the discoveries of Ghost Ranch, New Mexico, a lot of systematics work, and his work in Antarctica, just to name a sliver of the things he accomplished during his 96 years of life. Colbert's name for this 225 million year old agile bipedal predator translates to "Southern Cross Lizard" with the specific epithet being in honor of Brazilian paleontologist Llewellyn Ivor Price, who had actually collected the fossil. The fossil, as stated, is made up of quite a good portion of the post-cranial skeleton as well as the mandible. Hindlimbs, the pelvic girdle, and the vertebral column are nearly complete; however, the feet and forelimbs, ribs and cranial elements other than the mandible are lacking. All told, animals have been named on far less and the bones present indicate a predator that, at about 66lbs (30kg), 31in (80cm) tall, and 7.4ft (2.3m) long, was about the weight of the average Labrador Retriever but just a tad taller (and obviously longer). The remains that have been discovered and the primitive age of this dinosaur, however, have led to some educated guesses pertaining to the make up of the missing skeletal elements. Chief amongst these are depictions of the hands and feet of Staurikosaurus as five fingered and toed basal appendages. The running speed of Staurikosaurus, despite the primitive foot and pelvic girdle, is considered to be fairly quick given the structure of the legs. The long tail consisting of approximately 40 caudal vertebrae would have aided the quick little dinosaur in maintaining its balance at its higher speeds.

25 April 2013

Panoplosaurus the Loved

Japan loves dinosaurs!
Panoplosaurus, as we have seen this week, is quite a loved animal. There are cartoons and mentions in books and many other places. Why, then, is it not as readily distinguishable from other dinosaurs like its cousin Ankylosaurus? I shared the crochet patterns and many different information sources and I made note that Panoplosaurus is discussed in many different books. With all of these different resources surely we should have a more automatic reaction to a picture of Panoplosaurus or a more ready identification at least of the animal. Panoplosaurus is popular enough in the dinosaur continuum that it has appeared in Dinosaur King and was even given away by Nabisco in the past; though it was mentioned to be a species that does not exist. Panoplosaurus has also been popular in museums as it has been displayed all over the country (I do not know about internationally). Not many people really seem to dislike Panoplosaurus though, so it does not come as much of a surprise that it would be on display in so many museums.

24 April 2013

Lambe's Next Discovery

As has been discussed multiple times here, Lawrence Lambe was a prolific discoverer and describer of dinosaurs. Fortunately for him any rivalries he was a part of were not nearly as high profile as Marsh and Cope, which allowed him to focus a bit more on accuracy than volume; I think of the Marsh and Cope volumes of descriptions as having "machinegun accuracy" as opposed to the idea of one shot, one kill. Lambe was not, however, more often correct than Marsh or Cope, as the science has tweaked even his discoveries and ideas over the past century. Regardless, the point of bringing up Lambe is that we have his initial descriptions of this animal and can therefore look at the material secondhand rather than via many other sources. Over 200 scutes of armor, a good portion of a fore and a hind limb, a good portion of the cervical vertebrae articulated with the skull, pelvic and shoulder girdles and thoracic vertebrae were discovered together and delivered to Lambe. Lambe, however, did make an interesting mistake by placing Panoplosaurus, now known to be a Nodosaur, in the Stegosaur family (Stegosauroidea); he also assigned Euoplocephalus, another ankylosaur, to the stegosauria. Contained in the in depth descriptions of the skull we find that Lambe measured individual teeth in the skull and compared them to Stegosaurus, leading, in part, to his justification of this nodosaur as a stegosaur.

Lambe was not completely off, though, as the current convention holds that Stegosauria and Ankylosauria make up the clade Thyreophora as the Eurypoda (Scelidosauridae is also included outside Eurypoda but within Thyreophora). Lambe's attention to the detail of the armored scutes probably provided some of the best evidence, in later years, for the partitioning of the Eurypoda into Stegosauria and Ankylosauria, interestingly. I wish I had an exact paper to point to in reference to this change. Alfred Romer's 1956 Osteology of the Reptiles is widely considered, however, to be the definitive text for establishing Ankylosauria as a suborder within Thyreophora (Coombs and Maryanska. He divided the over 200 scutes into 7 major divisions; 1) Large plates; 2) Medium sized variable dimensions; 3) Moderately small keeled; 4) Small rectangular; 5) Small polygonal; 6) Small keelless; and 7) Irregularly shaped ossicles. He also included plates of the scutes, but my favorite plate is of the skull looking from front to back. Check it out:


References for today:
Coombs, W.P. and Maryanska, T. (1990). Ankylosauria. In Weishampel, D. B., Dodson, P., & Osmólska, H. (Eds.). . The Dinosauria. (456-483) Univ of California Press.
 
Lambe, L. M. (1919). Description of a new genus and species (Panoplosaurus mirus) of armored dinosaur from the Belly River Beds of Alberta. Transactions of the Royal Society of Canada series, 3(13), 39-50.

23 April 2013

Systematics and Panoplosaurus

Kenneth Carpenter wrote, a few years ago (1992 was the original publishing year), an article in a text collectively called Dinosaur Systematics: Approaches and Perspectives. The text as Carpenter writes it, though you cannot read it all online, uses Edmontonia and Panoplosaurus as examples for Ankylosaur systematic arguments. Carpenter has published many other writings concerning Ankylosaur systematics as well and discussed Panoplosaurus in many of the articles. Most of his published articles, unfortunately, appear in edited anthologies and are therefore unavailable online. Coombs and Maryanska also discuss Panoplosaurus' anatomy in the original edition of The Dinosauria; the newest edition Ankylosauria section is penned by Vickaryous, Maryanska, and Weishampel and, of course, still mentions Panoplosaurus. Paul's Princeton Field Guide to Dinosaurs also mentions Panoplosaurus and that it enjoyed forested floodplains, swamps, and marshes. While the cartoon yesterday noted that Tyrannosaurs were the main threat to Panoplosaurus, Paul makes note that the main threats to Panoplosaurus were most likely Daspletosaurus and Albertosaurus. Not many scholarly papers are uniquely geared toward Panoplosaurus, which is okay, but still gives us little to read if we do not own one of these books.

22 April 2013

Earth Day Post!

Happy Earth Day friends! Today I have two videos I want to share with you. One is a short informational cartoon starring our friend Panoplosaurus, and the other is a short computer model of the cranium and brain of our friend previously mentioned. The cartoon sort of speaks for itself and delivers some information in a manner which will be good for kids to digest it. The second video really does not say anything, but it is a nice visual and it is a good example of what rolls out of Dr. Witmer's labs from time to time at Ohio University. I am pretty sure at this point that everyone knows what to expect when they know the scans and models come out of his work and his student's work, but it is still fun to look at, so enjoy!

21 April 2013

The Children's Nodosaur

Panoplosaurus is a child-friendly dinosaur. Not only does it look as though it would make a great pet; in the human world this is the sort of dinosaur that would undoubtedly be selectively bred as a lap-dog. Perhaps that is the reason they are so well represented in the child-friendly web pages around the internet. Our favorite child-friendly fact page at Kids Dinos has page set aside with quick facts. Additionally, the coloring page needs of children, and adults, can be taken care of over at Enchanted Learning. As usual, the site allows for online coloring as well as printing the picture and coloring offline; I hate the waste of paper, but I love the feeling of colored pencils, so I am typically torn equally when presented with the option. There is not much in the form of toys/models available for sale, but for our friends that know how to crochet, and I wish I did right now, you can make your own toy Panoplosaurus with these crochet patterns available for purchase. Grandmas usually love knitting and crocheting, not that younger people do not, and they would probably love to make one for you, and with you even, if they know how to do those things!

20 April 2013

A Long Day Ended

©Brian Franczak
This is a late entry because I just got back in in the last few hours from doing some work on a National Wildlife Refuge. They were counting species of everything on the refuge. I helped with birds mostly. Anyhow, due to the lateness of it, and the fact that I am just plain tired today, I am not going to put up a lot of art today. Strangely enough, this was the perfect dinosaur for such an event to cause a lack of illustrations to be posted for. Panoplosaurus was a pretty basic nodosaur. Not only did it have a basic body plan, but it did not have many ostentatious ornamentations on its body. These things all coming together give us a fairly typical nodosaurian dinosaur, which is pretty much what we expect when we think of ankylosaurs and nodosaurs. That does not make this a bad thing at all, but it does make it a somewhat bland dinosaur in some aspects. I still think you look pretty nifty Panoplosaurus, even if you are kind of bland.

19 April 2013

A Panoply of Armor

Uncredited (I am on the lookout for it)
Back in January I discussed an infant dinosaur discovered in Maryland that came to be called Propanoplosaurus, meaning "before Panoplosaurus". Perhaps I should have followed that closely by the dinosaur that the name somewhat came from, but I obviously did not, because I am discussing it this week. As with many other large herbivores of the Canadian and Western US' Cretaceous era soils, this is a wide, heavy, armored animal. Panoplosaurus was big in most every way. Its head was heavy and covered, dorsally, in thick bone. The thick cranium of the animal is not much when compared to the scutes discovered along its back and even along the caudal vertebrae of the tail. A Nodosaur, Panoplosaurus mirus ("totally armored lizard"), weighs in at approximately 6000lbs (2721.6kg or about 3 tons) and reaches lengths of 23ft (7m) for a middle sized individual.

18 April 2013

A Good Giant Raptor Week

Looks a little naked though
I shared the image I posted with my wife last night. She freaked out. Apparently birds bigger than people are not very appealing to her; admittedly Great-tailed Grackles kind of freak her out with their size, let alone being a bird. For all of her freaking out around birds she does do a great job driving me around to photograph them, but I digress! Giant bird, giant Eumaniraptoran, or smallish dinosaur; whatever way you choose to describe Achillobator, it has been an impressive dinosaur to research and discuss. In terms of popularity out in the world, we have mentioned a small number of popular references already this week. What we have not seen as yet, however, is the video game contributions. Creators in Spore have gone to work making their own Achillobator models; I think this one is the most robust and interesting one to the left here. Additionally, and I find this kind of funny, there is apparently an island in World of Warcraft that has at least one giant dinosaur living on it that will occasionally produce an item called the Achillobator Ring when defeated. That is a different thing to share in terms of pop culture references generally shared on this site! Unfortunately, the popularity of the animal kind of stops there. In 2003 there was a short jolt on the dinosaur mailing list. That has pretty much disappeared from the record though (I found it on page 4 of the Google hits for Achillobator). Tomorrow I think we may start a week that is a little bit more popular, but I can never tell until we get really rolling. Hopefully this week will help Achillobator get some more attention; it is an interesting enough animal to deserve it!

17 April 2013

Close Cousins?

Utahraptor on top, Achillobator below. Used with permission as noted on the image.
Taken from A Field Guide to Mesozoic Birds and Other Winged Dinosaurs
Utahraptor and Achillobator were related, somehow. They were the largest raptors in their homelands. They were also strangely "backwards" in terms of the evolutionary lines of their family; some of their character traits seem rather basal for somewhat advanced dinosaurs. These animals were both large terrestrial theropods built with squat bodies (compared to other raptors) that housed large muscle masses more likely to wrestle opponents and overwhelm them with sheer strength than lightning quick attacks. That is not to say that neither of these animals may have been able to execute quick attacks at opponents with jaws or claws; both of which would be devastating weapons. Two hypotheses have been circulated as to the use of giant toe claws of raptors but I think that I would be correct in saying that the more popular hypothesis still is that the claw was used to stab and slice through the arc of motion of the leg. The claws that both of these predators possessed, though through extrapolation of bone shards alone for Achillobator at this point, would have cause massive damage with such behavior. The less popular hypothesis is that the toe claw was used as an anchor for grasping onto prey while teeth and hands shredded the vital arteries and soft paunches of large herbivores. There is a bit of evidence behind that sort of behavior but there is also support for the other behavior hypothesis. However, with animals such as Utahraptor and Achillobator the second hypothesis, that of a grappling animal rather than a quick striking animal, has quite a bit of merit.

Achillobator was an Asian animal, in modern context, and had a different landscape for a home. The Mongolia of 90 Mya was a semiarid desert, kind of like some of it is today. The Utah of Utahraptor, which is considerably older at 125 Mya, was a marshy mud flat with open tracts of land. The squatness of both animals was most likely an adaptation that favored the reduction in length of hindlimb to produce the ability to hide closer to the ground in the low scrub environments in which they lived. Utahraptor lived in a time devoid of large predators; allosaurids, ceratosaurids, and megalosaurids had all disappeared from the landscape during the existence of Utahraptor. Large carnosaur reintroduction into the landscape likely led to a loss of niche and subsequent dwindling of population and eventual extinction of Utahraptor. Achillobator lived alongside many other carnivores, though. Until we have a better range of existence data for Achillobator we cannot really surmise the events leading to its disappearance from the fossil record.

Reference of the day:
Martyniuk, M. P. (2012). A Field Guide to Mesozoic Birds and Other Winged Dinosaurs. Pan Aves.

16 April 2013

Books, Birds, and Elusive Papers

Scientific writing. I am still trying to wrap my brain around it. Over my lifetime I have developed a style, and it can be seen here quite well, but lately I have been tasked with writing scientific papers and they have not been pretty. One would think the more I read the better I would get at writing in that style, but not quite so yet. That makes the days I discuss papers that much more important in my own personal development. Today I, unfortunately, do not have many papers to share. I still have not found a way to get the original naming paper, not by the end of this week at least, but there are other essays and papers that refer to Achillobator in them. There are two papers that discuss evolution in Gondwana of dromaeosaurs and a paper on evolution of the dromaeosaur tail. The paper on Gondwana also describes a new Patagonian theropod (as of 2009). That theropod was named Austroraptor cabazai in the paper. The paper on dromaeosaur tail evolution also discusses and names a new dromaeosaur from Utah. Two specimens were not named but the third specimen was name Yurgovuchia doellingi. Achillobator comes into play in these papers in that the discussion of evolutionary lines in both papers mention Achillobator. Both Greg Paul's Princeton Field Guide to Dinosaurs and Matt Martyniuk's recently released Field Guide to Mesozoic Birds and other Winged Dinosaurs contain entries on Achillobator. Martyniuk's entry is longer and speculates a little on behavior inferred from the skeleton. Additionally, Martyniuk has illustrated a squat little Achillobator to accompany the entry (Martyniuk's "field guide" is much more like a modern fauna field guide in respect to illustrated specimens with entries).

15 April 2013

Not A Video Day

©Jaime A. Headden (cropped for today)
Movie Monday has a sad showing for Achillobator, which, given its low skeletal remains content, is not surprising but is unfortunate; this is a pretty fantastic animal as we have seen so far. There is one of those "tribute" videos with music that I am perpetually saying I do not like. The largest problem with that, however, is that a lot of the images used are of nondescript "megaraptors" and other animals that are not Achillobator. Therefore, rather than have a very short post about nothing, let us look specifically at the legs of our mythical warrior.

The legs of Achillobator, despite the overall size of the animal, are quite small. Tibia and tarsus both are extremely short compared to the femur, though, admittedly, the heads of the tibia and tarsus both appear to be either missing or broken and chipped (though I have to admit I am going off of 2nd hand illustrations still). Shorter legs generally require higher energy consumption than longer legs to cover equal distances. The Achilles' tendon of Achillobator, obviously lending itself to the name, was reported as having to have been rather large, however, even on the shorter leg. The large tendon and the short leg most likely packed a rather large punch, causing great damage through the arc of the swinging motion of the leg. Not possessing as much speed but, rather, being more like the muscle laden Utahraptor, Achillobator was probably much more likely to wrestle and bring down prey with power than tiring it out in pursuit. This, then, would also make it much more likely to be an ambush predator like a lion rather than a pursuit predator like a cheetah. Of course, this is not necessarily the view put forth by the paper, but I cannot state the author's viewpoint as I still do not have a copy of the paper.

14 April 2013

A Nice Day for Coloring

After a very windy night I am quite happy to say I have quite a few good things to share today. I do not want to go into anatomy today; I know I said a few days this week I may not do the "normal" themed topics of the day. Today is not one of those days. I have quite a few good links and pictures for today. First, let me say that there are quite a few bad links too. The Natural History Museum of London, for instance, has a pretty good set of information, until you get to the specific epithet, which is wrong. It could just be a spelling error, so let us not dwell on it! Another almost awesome fact site is found at AgeofDinosaurs.com. The only issue with their facts is that they do not tell the whole story of the discovery, instead using the year of publication as the year of discovery. Putting the two sites together and ignoring the two little mistakes makes for a good collection of facts. Combine those with these two coloring pictures and you have a good day to explore a new dinosaur with your loved ones:

Artist's Page

13 April 2013

Looking at Skeletons

©Jaime A. Headden
The skeleton of Achillobator, as we have noted, is not complete. The fact that it was, and still is sometimes, thought to be a chimera is because the associated elements seem to come from all over the maniraptoran family. Were this a whole skeleton it would, because it possesses so many different elements, be a rather interesting living (well, dead) case study in skeletal transitions. Arguably the most recognizable element of the dromaeosaur family that is thought to be present, a second hypothesis places this bone on the hand, is the large "killing" claw of the "raptors". The size and length are inferred based on the heel of the phalanx that is said to represent the claw. Other elements of the skeleton also refer the animal to the maniraptoran family including the maxilla that was recovered.

The maxilla appears to be the end of the snout, thus encompassing the pre-maxilla as well, in some renditions though we can see clearly in the previous illustration that the maxilla only is interpreted as being represented by this piece of the puzzle. The ridges shown in what we would expect to be a widely opened fenestra are notably rare for all theropods, but it is seen in at least one other theropod. This rarity adds to the mystery and further confounds the findings with the teeth. The teeth are consistent with the sizes and ratios of length, width, curvature, etc. found in other dromaeosaurus and even troodontids. Visual comparison of the overall shape of the teeth supports that assertion, though we know just looking at something can be considered weaker evidence than the measurements of the teeth; thankfully we have both.

©Jaime A. Headden
Key to pelvises: A,
Deinonychus antirrhopus; B, Adasaurus mongoliensis; C, Unenlagia comahuensis; D, Achillobator giganticus; E, Microraptor zhaoianus; F, Velociraptor mongoliensis; G, Sinornithosaurus millenii; H, Rahonavis ostromi; I, Bambiraptor feinbergorum; J, Archaeopteryx lithographica; K, Sinovenator changii.
One of the other issues that has been raised with the remains attributed to Achillobator is the odd morphology of the pelvic girdle. Looking at the pelvis, D in Mr. Headden's illustration, we can compare many of the elements to the other pelvises of maniraptorans that are also illustrated up next to it. Of particular note are the pubic boot, the "lowest" part of the pelvis in layman's terms. The shape is clearly different from all of the others in that it is almost completely ventrally flexed and it projects both anteriorly and posteriorly at the same time. This is a carnosaur related trait more often than it is a maniraptoran trait, as we can see above. Compare it to this carnosaur's pelvis.



References
Headden, J. A. (2002). Achillobator: Theropod Puzzle. Retrieved April 13, 2013, from Qilong: http://qilong.8m.com/Achillobator.html

12 April 2013

Tackling Another Tough Opponent

Long time readers know that I enjoy, perhaps even love, taking on difficult cases from time to time around here. This is actually becoming slightly more normal as we get lower in the popularity barrel of dinosaurs. When we first started out the Triceratops and T. rex icons still stood before us and there were vast fields of papers, opinions, models, and other research to draw upon. Then we found our first few "iffy" animals; dinosaurs that were in doubt or, like Monoclonius, had actually been relegated (reassigned) to other genera and referred to other species. This week we shall continue looking at a problem child, in some eyes still despite some positive arguments for the validity of the subject, of the dinosaur world. At approximately 16 feet (4.9m) long and possessing bones that seem to make it drift up and down the family tree of the maniraptorans, this week's dinosaur was called Achillobator giganticus. The animal was named based on the fact that the Achilles' tendon would have been enormous in this animal and the word "bator" in Mongolian means hero. The specific epithet giganticus kind of speaks for itself, I think, in relation to what we will see of it and how it related to other maniraptorans. The trouble that has surrounded this large animal is that the bones, those bones that cause its relationship to winnow up and shimmy down the family tree, are characteristically in many different positions of expected development and this has led to the cry of "CHIMERA!" by some in the paleontology community over the years. During this week we will look over these bones and hopefully by the end of the week (I may need to tweak some of the days' themes to cover everything unique about this animal), we will all be able to form our own thoughts on the validity and perhaps even a generalized relationship of Achillobator with other maniraptorans.
©Matt Martyniuk

11 April 2013

The Charismatic Stego

From How to Draw Incredible Dinosaurs to its inclusion in Dinosaur King, Gigantspinosaurus has been made quite welcome in the popular culture of the world. Considering that it is little understood and the exact physical orientation of its namesake spikes are still debated in many circles, it is interesting that it is popular already. In part it owes its face to the public to the fact that it has been around as long as it has even with its "dubious" name being out there for the first half of its existence (in our knowledge that is of course). Strangely, however, I cannot seem to find toys and models of Gigantspinosaurus, and we can all admit that that would make a fantastic toy/model. There are a myriad of Dinosaur King cards that depict Gigantspinosaurus, but that is a little bit different; a card game is not the same as a 3-D model. There was this promotional piece from Dinosaurs Unearthed, but that does not really qualify as a mass market toy. Spore, though I could not find videos this week, does have some creators that have engineered little Gigantspinosaurs, like the one found in this image.