Showing posts with label dinosaurs. Show all posts
Showing posts with label dinosaurs. Show all posts

Thursday, February 20, 2014

And now for something slightly different

You all deserve a brief respite from the dead fish and Avaceratops update barrage. What better excuse to talk about our big Daspletosaurus Pete III then? It's about the only dinosaur we have that people tend to ask about anyway. We've had an opportunity to catch up on a few projects lately and are able to spend some time in preparing the final few bones from their field jackets, while also restoring the skull bones to get them ready for 3d laser scanning and printing.

Bryan finishing the neural arch of caudal 2
I'm sure you have heard about the special challenges that preparing Pete III poses. I even did a paper on it, which is posted on my academia.edu page. When done, the bone itself is pretty stable, but it just looks somewhat ugly since it's made up of thousands of small fragments. We've adopted a technique using tinted hydrocal to fill in these small surface gaps to help give the bones a little more strength as well as make them look less pixellated (to borrow a term from a friend).
Left jugal after initial prep
Left jugal beginning restoration
Left jugal after finishing
Pixellated right quadratojugal

Much better with plaster
And in further comparison to the size of Pete III vs. Tyrannosaurus rex, here's a teaser comparing the left ectopterygoids of our Daspletosaurus vs a mounted copy of a rex. Not a whole lot of difference there overall.
Can't wait to get finished with this head...

Friday, August 3, 2012

Sometimes you get the Trike, sometimes it gets you

Jacob and I are back from a second trip to the Hell Creek, working on some sites we discovered on the first trip. We spent the majority of our efforts on the site that produced the left brow horn form the first trip.

Beginning of the dig. Chunky bone fragments circled in orange paint.
We expanded the excavation to the north by about 8 feet, tracing a few bone fragments. The overburden was low, and digging relatively easy, but the bone exposed were rounded isolated small chunks. Not especially promising.

Braincase with distinctive ball of the occipital condyle
As we worked back closer to where the brow horn was found, we started encountering more recognizable bones. Unfortunately, the skull was all that was present, and even then it was partial. In the end we recovered a squamosal, predentary, braincase and maxilla, along with some fragile fragments that will be worked on in the lab.



First batch of bones jacketed, waiting for plaster to cure

End of the dig. The generator and electric jackhammer was a real back-saver!
Headed back out in a few weeks, hopefully more luck then!

Monday, January 30, 2012

Baryonyx in Colordo: 100th post

It's been 1oo posts since I started this blog. Some people would have something special planned out for an occasion like this. Plan? Why start now?

Amazingly, the post I did about a year ago on our asembly of a cast Baryonyx skeleton is still the main traffic driver on this blog, after the updates of course. In order to celebrate, I'm putting up a few more pics of the cast for future google image surfers.
With a copy of the Maidstone slab in the background

Nice paws
This specimen is on display for a few more weeks in the RMDRC, before getting shipped off to its new home overseas. 

34 feet (11m) long is big for almost any theropod



Friday, December 9, 2011

Show Thescelosaurus some love

When is a dinosaur not a dinosaur? When it's fairly dull I guess. Just look at Thescelosaurus. Not brainy, not much in the way of fangs, claws, armor, clubs, or anything else sexy. It's also a fairly rare dinosaur, with just a handful of reasonably complete specimens. We at the RMDRC have been lucky, preparing the only complete skull so far (on "Bert"), as well as now preparing a pretty dang complete skeleton, "Jonathan".

Right leg from the former display
Jonathan was discovered in 2006 in the Hell Creek Formation of Montana. It was nearly complete, minus the tip of the tail and the head/neck where it had eroded out into the gully. Lying belly-up, once show prepped, it nearly looked like it died just yesterday.


Main jacket

Look at that cute little first chevron
We have now started to prepare all of the bones free of the matrix. We will restore them, mold them, reconstruct the missing bits, and offer a cast of this big Thescelosaurus (13-14 feet or 4m long) for sale to institutions. The original will be mounted in 3d on a steel armature. That last bit is a LOT of work, but it's also pretty satisfying and a bit of fun too, especially if you enjoy doing metal work!

Friday, November 18, 2011

Daspletosaurus prep update

Jacob and I have been hammering away at the remaining small jackets of Pete III. By small I mean things less than the 4 ton main jacket monstrosity that we'll eventually have to confront. This week we've finished the left femur and ilium, along with a slew of gastral elements, vertebrae, and other bits and pieces.

Anterior dorsal of Pete III compared to Stan
The ilium has a strange mass of punky bone on the medial face of the pubic peduncle. We've seen a few instances of old age related pathology on this specimen, it wouldn't surprise me to find more.


Medial surface of left ilium, 42 inches long


Before long, we'll be started on the pathological tail section. Can't wait!

Caudal view of left femur.

Friday, November 11, 2011

Daspletosaurus prep restarts: this time with skull bones

While I was away soaking up pathogens at SVP in Las Vegas last week, paleotech Jacob Jett has been busy preparing some of the jackets from the weathered edge of Pete III's excavation. The bone was in difficult shape to begin with (earning the nickname "The pixelated Tyrannosaur" at SVP) before seeing several hundred Montana freeze-thaw cycles, making this prep work one of our greatest challenges to date. However, results are here! Skull bones so far include both quadrates, a jugal, both quadratojugals, a spenial, pterygoid and possible surangular, with more to come. No toothy bits yet though.

The left quadrate. Actually recognizable!

Dorsal vertebra #1, giving you an idea of the sheer size of Pete III. Transverse process span is 15 inches (38cm)

Surprise! Manual phalanx!
We still have many jackets (including the majority of the big 4-ton monstrosity) to prepare, however we're confident that the majority of the skeleton and perhaps 20-30% of the skull is here. Check back for more updates!

Wednesday, September 28, 2011

Light at the end of the Triceratops tunnel

We're back from another great Denver Gem and Mineral show. I even got Bob Dietrich to sign my copy of "Boneheads" by Richard Polsky. Dr. Bakker had some good input about javelinas, and we got our Bacculites jaws back from being prepared by Neal Larson.
Captain Jacob on the SS Pointyface

We're now back in our final push to get this giant Triceratops skull built and out of our workspace. We figure less than 3 weeks to go. All assembly is finished, save for installing the missing maxillary teeth. Steel work is also done (I incinerated 3 t-shirts during that process), all that it really left is details details details. Also painting. Today I should hopefully be finished hollowing out the ironstone from the orbits in the last bit of preparation.
A month's worth of work. Also I made the table.

We've got a space picked out in the museum and will let all of our readers know when it goes on display, so you can come visit it in person. Sad thing is, I don't think this Triceratops has a name yet...

Tuesday, February 8, 2011

Viral Post: "What Should Everyone Know about Paleontology"

Dr. Thomas Holtz, who visited our lab last year, recently shared his insights in a response to a question posted on the Dinosaur Mailing List. I muddle through their archives online a bit, and there are sometimes some good posts, but this one seems to have taken on a life of its own, being featured on SV-POWLove in the Time of Chasmosaurs, and Superoceras so far. I think it warrants more exposure, so I'll chip in my contribution on teh RMDRC Paleo Lab blog. Hopefully the formatting didn't get too messed up. Also, be sure to check out the linked blogs mentioned in the post.


 



“What Should Everyone Know About Paleontology?”



Thomas R. Holtz, Jr.
The title question was recently asked by Roberto Takata on the Dinosaur Mailing List (http://dml.cmnh.org/2011Feb/msg00020.html).
I think that is a good question. What really are the most important elements of paleontology that the general public should understand? I took a shot at coming up with a list of key concepts (http://dml.cmnh.org/2011Feb/msg00027.html andhttp://dml.cmnh.org/2011Feb/msg00029.html), based on experiences with teaching paleontology and historical geology and with less-formally structured outreach to the public. I have offered this list (cross posted at the Superoceras andArchosaur Musings blogs) as a way for it to reach a wider audience. That this is Darwin Week makes it even more appropriate, as we should use this occasion to encourage a better understanding of the changes of Earth and Life through Time for the public at large.
Much as I might like to think otherwise, the specific details of the hindlimb function of Tyrannosaurus rex or the pneumatic features of brachiosaurid vertebrae really are not the most important elements of the field. Understanding and appreciating the nitty gritty details of the phylogeny and anatomy of any particular branch of the Tree of Life are not really necessary for everyone to know, any more than we would regard detailed knowledge of bacterial biochemistry or the partitioning of minerals in a magma chamber to be significant general knowledge. (Indeed, these latter two items are actually far more critical for human society than any specific aspect of paleontology, and so from a certain point of view really more important for people to know than the History of Life.)
That said, all human societies and many individuals have wondered about where we have come from and how the world came to be the way it is. This is, in my opinion, the greatest contribution of paleontology: it gives us the Story of Earth and Life, and especially our own story.
I have divided this list into two sections. The first is a list of general topics of paleontology, touching on the main elements of geology that someone would need to know for fossils to make any sense. The second is the more specific list of key points in the history of life.
(NOTE: as the idea of this list is that it should be aimed at the general public, I have tried to avoid technical terminology where possible.)

General

  • That rocks are produced by various factors (erosion -> sedimentation; metamorphism; volcanic activity; etc.)
  • That rocks did not form at a single moment in time, but instead have been and continue to be generated throughout the history of the planet.
  • That fossils are remains of organisms or traces of their behavior recorded in those rocks.
  • That rocks (and the organisms that made the fossils) can be thousands, millions, or even billions of years old.
  • That the species discovered as fossils, and the communities of organisms at each place and time, are different from the same in the modern world and from each other.
  • That despite these differences that there is continuity between life in the past and life in the present: this continuity is a record of the evolution of life.
  • That we can use fossils, in conjunction with anatomical, molecular, and developmental data of living forms, to reconstruct the evolutionary pattern of life through time.
  • That fossils are incomplete remains of once-living things, and that in order to reconstruct how the organisms that produced them actually lived, we can:
    • Document their anatomy (both gross external and with the use of CT scanning internal), and compare them to the anatomy of living creatures in order to estimate their function;
    • Examine their chemical composition, which can reveal aspects of their biochemistry;
    • Examine their microstructure to estimate patterns of growth;
    • Model their biomechanical functions using computers and other engineering techniques;
    • Investigate their footprints, burrows, and other traces to reveal the motion and other actions of the species while they were alive;
    • And collect information of the various species that lived together in order to reconstruct past communities.
  • However, with all that, fossils are necessarily incomplete, and there will always be information about past life which we might very much want to know, but which has been forever lost. Accepting this is very important when working with paleontology.
  • That environments of the past were different from the present.
  • That there have been episodes of time when major fractions of the living world were extinguished in a very short period of time: such data could not be known without the fossil record.
  • That entire branches of the tree of life have perished (sometimes in these mass extinction events, sometimes more gradually).
  • That certain modes of life (reef formers, fast-swimming marine predators, large-bodied terrestrial browsers, etc.) have been occupied by very different groups of organisms at different periods of Earth History.
  • That every living species, and every living individual, has a common ancestor with all other species and individuals at some point in the History of Life.

Specific

Honestly, despite the fact the specific issues about specific parts of the Tree of Life are the ones that paleontologists, the news media, the average citizen, etc., are more concerned with, they really are much less significant for the general public to know than the points above. Sadly, documentary companies and the like keep on forgetting that, and keep on forgetting that a lot of the public does not know the above points.
Really, in the big picture, the distinction between dinosaurs, pterosaurs, and crurotarsans are trivialities compared to a basic understanding that the fossil record is our document of Life’s history and Earth’s changes.
Summarizing the key points of the history of life over nearly 4 billion years of evolutionary history is a big task. After all, there is a tendency to focus on the spectacular and sensationalized rather than the ordinary and humdrum. As Stephen Jay Gould and others often remarked, from a purely objective external standpoint we have always lived in the Age of Bacteria, and the changing panoply of animals and plants during the last half-billion years have only been superficial changes.
But the question wasn’t “what should a dispassionate outsider regard as the modal aspect of the History of Life?”; it was “What should everyone know about paleontology?” Since we are terrestrial mammals of the latest Cenozoic, we have a natural interest in events on the land and during the most recent parts of Earth History. That is a fair bias: it does focus on who WE are and where WE come from.
That said, here is a list of key concepts in the history of life. Other researchers might pick other moments, and not include some that I have here. Still, I believe most such lists would have many of the same key points within them.
  • Life first developed in the seas, and for nearly all of its history was confined there.
  • For most of Life’s history, organisms were single-celled only. (And today, most of the diversity remains single-celled).
  • The evolution of photosynthesis was a critical event in the history of Earth and Life; living things were able to affect the planet and its chemistry on a global scale.
  • Multicellular life evolved independently several times.
  • Early animals were all marine forms.
  • The major groups of animals diverged from each other before they had the ability to make complex hard parts.
  • About 540 million years ago, the ability to make hard parts became possible across a wide swath of the animal tree of life, and a much better fossil record happened.
  • Plants colonized land in a series of stages and adaptations. This transformed the surface of the land, and allowed for animals of various groups to follow afterwards.
  • For the first 100 million years or so of skeletonized animals, our own group (the vertebrates) were relatively rare and primarily suspension feeders. The evolution of jaws allowed our group to greatly diversify, and from that point onward vertebrates of some form or other have remained apex predators in most marine environments.
  • Complex forests of plants (mostly related to small swampland plants of today’s world) covered wide regions of the lowlands of the Carboniferous.
  • Burial of this vegetation before it could decay led to the formation of much of the coal that powered the Industrial Revolution and continues to power the modern world.
  • While most of the coal swamp plants required a moist ground surface on which to propagate, one branch evolved a method of reproduction using a seed. This adaptation allowed them to colonize the interiors, and seed plants have long since become the dominant form of land plant.
  • In the coal swamps, one group of arthropods (the insects) evolved the ability to fly. From this point onward insects were to be among the most common and diverse land animals.
  • Early terrestrial vertebrates were often competent at moving around on land as adults, but typically had to go back to the water in order to reproduce. In the coal swamps one branch of these animals evolved a specialized egg that allowed them to reproduce on land, and thus avoid this “tadpole” stage.
  • These new terrestrial vertebrates—the amniotes—diversified into many forms. Some included the ancestors of modern mammals; others the ancestors of today’s reptiles (including birds).
  • A tremendous extinction event, the largest in the age of animals, devastated the world about 252 million years ago. Caused by the effects and side-effects of tremendous volcanoes, it radically altered the composition of both marine and terrestrial communities.
  • In the time after this Permo-Triassic extinction, reptiles (and especially a branch that includes the ancestors of crocodilians and dinosaurs) diversified and became ecologically dominant in most medium- to large-sized niches.
  • During the Triassic many of the distinctive lineages of the modern terrestrial world (including turtles, mammals, crocodile-like forms, lizard-like forms, etc.) appeared. Other groups that would be very important in the Mesozoic but would later disappear (such as pterosaurs and (in the seas) ichthyosaurs and plesiosaurs) evolved at this time.
  • Dinosaurs were initially a minor component of these Triassic communities. Only the tall, long-necked sauropodomorphs were ecologically diverse during this time among the various dinosaur branches. However, a mass extinction event at the end of the Triassic (essentially the Permo-Triassic extinction in miniature) allowed for the dinosaurs to diversify as their competitors had vanished.
  • During the Jurassic, dinosaurs diversified. Some grew to tremendous size; some evolved spectacular armor; some become the largest carnivorous land animals the world had seen by this point. Among smaller carnivorous dinosaurs, an insulating covering of feathers had evolved to cover the body (possibly from a more ancient form shared by all dinosaurs). Among the feathered dinosaurs were the ancestors of the birds.
  • Other terrestrial groups such as pterosaurs, crocodile-ancestors, mammals, and insects continued to diversify into new habits.
  • During the Jurassic and (especially) the Cretaceous, a major transformation of marine life occurred. Green-algae phytoplankton were displaced by red-algae phytoplankton (which continue to dominate modern marine ecosystems). A wide variety of new predators—advanced sharks and rays, teleost fish, predatory snails, crustaceans with powerful claws, specialized echinoids, etc.—appeared, and the sessile surface-dwelling suspension feeders that dominated the shallow marine communities since the Ordovician became far rarer. Instead, more mobile, swimming, or burrowing forms became more common.
  • During the Cretaceous one group of land-plants evolved flowers and fruit and thus tied their reproduction very closely with animals. Although not immediately ecologically dominant, this type of plants would eventually come to be the major land plant group.
  • The impact of a giant asteroid—coupled with other major on-going environmental changes—brought an end to the Mesozoic. Most large-bodied groups on land and sea, and many smaller bodied forms, disappeared. The only surviving dinosaurs were toothless birds.
  • The beginning of the Cenozoic saw the establishment of mammals as the dominant group of large-bodied terrestrial vertebrates. Early on mammals colonized both the sea and the air as well.
  • During its beginning the Cenozoic world was warm and wet, much like the Cretaceous. However, a number of changes of the position of the continents and the rise of mountain ranges caused the climates to cool and dry.
  • As the world cooled and dried, great grasslands developed (first in South America, and later nearly all other continents).
  • Various groups of animals adapted to the new grassland conditions. Herbivorous mammals became swift runners with deep-crowned teeth, often living in herds for protection. Mammalian predators became swifter as well, some becoming pack hunters.
  • Other new plant communities evolved, and new animal communities which inhabited them. The rise of modern meadows (dominated by daisy-related plants and grasses) saw the diversification of mouse-and-rat type rodents, many frogs and toads, advanced snakes, songbirds, etc.
  • A group of arboreal mammals with very big brains, complex social communities, and gripping hands—the primates—produced many forms. In Africa one branch of these evolved to live at mixed forest-grassland margins, and from this branch evolved some who became fully upright and moved out into the grasslands.
  • This group of primates retained and advanced the ability to use stone tools that its forest-dwelling ancestors already had. Many branches evolved, and some developed even larger brains and more complex tools. It is from among these that the ancestors of modern humans and other close relatives evolved, and eventually spread out from Africa to other regions of the planet.
  • About 2.6 million years ago a number of factors led to ice age conditions, where glaciers advanced and retreated. Various groups of animals evolved adaptations for these new cold climates.
  • The early humans managed to colonize much of the planet; shortly after their arrival into new worlds, nearly all the large-bodied native species disappeared.
  • At some point before the common ancestor of all modern humans spread across the planet, the ability to have very complex symbolic language evolved. This led to many, many technological and cultural diversifications which changed much faster than the biology of the humans themselves.
  • In western Asia and northern Africa (and eventually in other regions), modern humans developed techniques to grow food under controlled circumstances, leading to true agriculture. (Other cultures are known to have independently evolved proto-agricultural techniques).
  • This Neolithic revolution allowed for the development of more settled communities, specialization of individual skills within a community (including soldiers, metallurgists, potters, priests, rulers, and with the rise of writing, scribes).
  • From this point we begin to get a written record, and so the historians can take up the story…
This list is obviously not comprehensive, and there are many elements that I had to ignore to keep it relatively short. Still, I hope this overview helps put where we as a species fit into the larger perspective of Life’s long voyage, a voyage that could only have been traced by the study of fossils.

Wednesday, October 6, 2010

New Book by Greg Paul


I've just been sent a copy of Gregory S. Paul's new book, The Princeton Field Guide to Dinosaurs! The 320 page hardcover volume is jam-packed with over 600 illustrations of over 735 different types of dinosaurs, many of which even I have not heard of before. Skeletal reconstructions are supplemented with color pencil illustrations and in a few cases stunning environmental reconstructions. I must admit there is a huge amount of information packed into this book, and even a hyper-dino-nerd like me has not had a chance to read every single word of it yet. Luckily it is very heavily illustrated, for those of us that cheat by looking at pictures.

The book begins with a 65 page section of text and illustration covering dinosaur research, anatomy and biology. After that it dives headlong into the dinosaurs, arranged by type. Not surprisingly the theropods are first. Each species of dinosaur is listed with a brief description giving their size, how much of the animal is known, distinguishing characteristics, age, distribution and some special notes. Several of TPI's dinosaur specimens are illustrated including "Sandy" the Pachycephalosaurus and "C1/C2" the unnamed North American oviraptor now housed at the Carnegie Museum.

Paul takes some liberties with the taxonomic assignments, seemingly destroying some types of dinosaurs and ruining people's childhoods in the process, however this is a general interest book, not intended for use by scholars. Parents with children interested in dinosaurs may have to spend some time explaining what happened to Lambeosaurus, Torosaurus or even Daspletosaurus. And then there is the seeming revival of Brontosaurus, an issue that sometimes makes me want to pull out what little hair I have left! On the bright side there is elimination of Opisthocoelocaudia, so at least we don't have to stumble through that name anymore.

Would I recommend this book? Most certainly! It is leaps and bounds better than the stuff I had available to me as a child, and it would have kept my interest for days on the first read-through. The price is right too at $35.00, and can be found online for even less. If you're a parent that has a dino-lover in the family, this would make an excellent holiday gift!

Thursday, February 4, 2010

Daspletosaurus vs. T-rex


One of Pete 3's humerus compared to a cast of Peck's Rex. The other humerus is awiting removal from the main jacket.

Friday, January 29, 2010

Pete 3 now published!

For all of you out there keeping tabs on our Daspletosaurus prep projects (which seem to be hitting high gear again), you probably know how much I complain about the matrix and bone quality issues on them. For BCT, it's soft-ish bone locked in a hard sandstone with Ironstone concretion. On the exact opposite end of the spectrum it is Pete 3 with very soft sandy matrix encasing super fragile and shattered bones.

I did a poster presentation on the Pete 3 issue at the first Fossil Preparations and Collections Symposium that Matt Brown helped host in 2008. The paper is now available online with the entire collection of presentations from the meeting.

Congrats Matt on making the volume available, and I hope to see some blog readers at this years meeting in Chicago.

Monday, January 18, 2010

Daspletosaurus progress


If you've been following the RMDRC newsletter since our museum opened, you're probably familiar with our BCT Daspletosaurus n. sp. specimen, nicknamed "Sir William". If so, skip ahead a bit.

BCT is a tyrannosaur discovered in 2001 in central Montana. It was originally thought to be in the Hell Creek Formation, making it a small Tyrannosaurus rex. Later, in 2005, it was discovered that the rocks were actually lower Judith River Formation, meaning that it is most likely Daspletosaurus. This specimen is an adult at 16 years of age (as determined by Greg Erickson) but displays some non-traditional Daspletosaurus traits, such as only 13 dentary alveoli (lower jaw tooth sockets), incidentally the same number as normally found in T. rex. Curious.

The excavation was very difficult, and took the summers of 2002 and 2003. The bones were encased in a combination of hard sandstone and ironstone concretions. Preparation was likewise slow.

This cervical vertebra is one of the last bones to be prepared from BCT, starting out as a 40 pound block of hard hard rock. After 30 hours of air scribe and air abrasion work this giant and beautiful bone is nearly done. Good job, Jacob, in getting this specimen ready for display!

Tuesday, December 8, 2009

RMDRC on VOA

We were filmed for a Voice of America feature a while back, and now it is online. Judging by the length of my hair I'd assume it was during field season.


Wednesday, November 25, 2009

Fossil of the week: revived!


I've been slacking, I admit it. Here's the challenge of the week: The photo below is definitely a squamosal off of a chasmosaurine ceratopsian. The question is which one? Pleas guess int he comments section.

Monday, May 4, 2009

Fossil of the Week 5/2/09


For this week's dinosaur, we venture up to Montana and the Judith River Formation, 75 million years ago in the late Cretaceous. Larry, a rancher who loves to hunt for dinosaurs near his home, was exploring badlands with Dr. Kraig Derstler during the summer of 2007. He had just finished wagering Kraig the princely sum of 2 quarters that he could find a diggable dinosaur fossil first when he came across hadrosaur bone fragments weathering out of a very steep slope. A bit of excavation revealed a few bones clustered together, luckily a RMDRC field crew was already en route to Montana, and we would spend the next month at the site.

In the photo, Dr. Kraig Derstler and Paleo Tech Jacob Jett work on breaking up a large sandstone block above the dinosaur (under the white cloth near their feet). Small man-portable jackhammers help tremendously with digs like this.

Most of Joyce (Named after Larry's wife, whoever finds the dinosaur gets to name it) was buried fairly quickly, with only a few shed tyrannosaur teeth in the quarry indicating limited scavenging activity. Unfortunately, not long after Joyce was buried, a small creek had cut through the site removing most of the tail. Somehow knowing it had been missing for 75 million years made us feel a bit better. From the limbs, vertebrae and skull were were able to tell that it was a lambeosaurine duckbill dinosaur, one of the types with a head crest. The pile of bones was so extensive that we had to remove most of it in one large jacket, and slide it up nearly 50 feet of slope to load on a trailer. Preparation is ongoing, and we hope to have some bones on display in the coming months.

Joyce made her television debut in 2007 as well, with NBC Nightly News and ABC (Australia) both having camera crews visit us at the dig site.

Monday, April 20, 2009

Fossil of the Week 4/20/09


Back on the dinosaur side of things, we're working on a very large Triceratops skull. This unnamed skull was discovered in 1999 by Mike Triebold in Harding County, SD, and has been taking up a lot of room in storage ever since. We opened the jacket at the end of March and have been working at it in small increments ever since. There is a large area of ironstone concretion on this, the down side, making preparation difficult and time consuming. Once cleaned and stabilized, we'll rotate the jacket upright and work on the other side, hoping to have a 3d skull mounted in a few months. As you can see, it is missing its beak, lower jaws and a portion of frill. These items will be restored later with plastic and epoxy putty.

The interesting things about this skull is the morphology preserved. It has a relatively large nasal horn, yet short and fat browhorns. There is a high degree of variation known in Triceratops, primarily because there are more skulls known than skeletons. In fact, Triceratops skulls are among the most common dinosaur fossils discovered in the Hell Creek Formation. This is the exact opposite of how we find other dinosaurs.

Monday, March 30, 2009

Welcome to the paleo lab


Welcome to the RMDRC's paleo lab blog. We're a working preparation, molding, casting and mounting lab in Woodland Park, Colorado. This blog is intended to give you a glimpse at more of the projects we're working on both here and in the field than what we're able to show in the monthly newsletter. Constructive questions and comments and suggestions are welcome.

We specialize in late Cretaceous marine reptiles, fish and dinosaurs, however who knows what kind of project may pop up.

To start, here's an update on a long-running project of ours, Pete 3, RMDRC 06-005, a Daspletosaurus torosus specimen that we excavated in 2006 from the Judith River Formation in central Montana. It's in a very splintered condition, but we've developed techniques to allow us to prepare this material in order to mold it (paper in press). Currently there are 67 bones prepared, mostly ankle, pes and caudal elements. We still have an estimated 200 bones to work on. It is hard to tell for sure as we had to be very cautious in the field and expose as little as possible before jacketing. This gives us happy surprises of additional bones in the jacket.

We estimate Pete to be about 11m (36 feet) long, and it should take us a good year to prepare all of the material. Scapula-coracoid is 1100mm long, mt II (in photo) is 460mm. Prep is now concentrated on a medium-sized (we'll rate it as a 2-hernia) jacket with the left ilium and a cervical vertebra, as well as another similar sized jacket with articulated mid caudal vertebrae and chevrons.