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Meet the Project Participants: Bruce Woollatt

September 28, 2009 1 comment
Bruce Woollatt, with one of his sculptural creations

Bruce Woollatt, with one of his sculptural creations

We next decided to interview Bruce Woollatt, another one of our regular data contributors. Bruce may be well-known to many of you who follow the Dinosaur Mailing List as the person who is building the 1/10 scale T. rex – in addition to his artistic talents, he has done a fantastic turn at verifying and entering all sorts of data from old and obscure literature!

Tell us a little bit about yourself. Where are you from? What do you do (professionally)? Any other interesting facts?
I was born, raised and live in London, Ontario, Canada which is sadly lacking in nearby Mesozoic exposures. My stay on Earth has lasted 47 orbits of the sun so far. I’ve had a lifelong interest in dinosaurs, having never “outgrown” them as so many kids do. My academic background is in history and philosophy (rather than science) but I earn my keep in the wonderful world of retail sales in a local camera shop. Go figure. I enjoy photography, reading and building dinosaurs. Over the years I’ve done a number of dinosaur sculptures and murals for the London Regional Children’s Museum including a life-size head of Parasaurolophus. You can see these here. My current project is a 1/10 scale T.rex skeleton which I am building for my own enjoyment as an on-line project at conceptart.org. You can follow along as I post progress reports here.

Why did you decide to participate in the ODP?
I decided to join the ODP because I thought it would be neat to make a contribution (however small) to paleontology. I’ve never dug into an outcrop but I’ve had plenty of experience digging into libraries!

So far, what has been the best part of the ODP for you, and why?
For me the best part of the ODP has been passing along the work of others, being a link in the chain. Some of the materials I was going through were nearly a century old; while nothing next to the sweeping expanse of time that paleontology routinely traverses, a century is a long time for us as individuals. Most of the data I was going through had been collected and published by people who are now dead; indeed some had died decades before I was born. I wondered what they would have thought of all the things we’ve learned in the meantime and all the new techniques that have been brought to the study of ancient life. I think they would have been amazed; I think they would have wanted to join in the dance. I feel that in a very small way I am helping them do just that. It has been an honour and a privilege to help pass on their legacy while at the same time contributing to new uses of that knowledge.

What have you learned from your participation in the ODP?
I have learned a bit about the collegial nature of science. Not that I am a scientist myself, but I do get a sense of the collaborative aspect of the enterprise. While I have never met any of the other people on the ODP, looking at the verification list and public data and I can see I’m a member of a team. A very busy team it is too. That’s cool!

What advice would you give those who might be interested in helping out with the ODP?
My advice is this: be your own verifier. Check stuff carefully and be sure you’ve entered things in the right boxes. Sometimes this can be tricky because once you’ve scrolled lower down on the data entry table the column headers disappear and it’s all too easy to enter a left femur figure as a right femur or as an unspecified femur. I know; I did it. More than once. Something I did that was helpful in avoiding this was to write out on a sheet of paper the code letters for the different measurements so that I knew that column AZ was the correct space to enter the length of the right femur, BA for the left femur, etc. Also, don’t forget to enter the page number(s) on which you found your data. (yes, this too is the voice of experience).

Categories: About Us, Interview

Meet the Project Participants: Christian Foth

September 26, 2009 2 comments

After a whole bunch of blather from me, Mike, and Matt, we figured it would be good to shut up for a little while and introduce some of our other project project participants. First on the list is Christian Foth, one of our most prolific database contributors. We sent some questions to Christian, and this is what he had to say [we've made very minor edits for style]:

Christian Foth in the Field

Christian Foth in the Field

Tell us a little bit about yourself. Where are you from? What do you do (professionally)? Any other interesting facts?
My name is Christian Foth and I come from Rostock. This is a little city in the north of Germany (maybe 200,000 inhabitants). I am 24 years old and study biology at the University of Rostock. My main subjects are zoology and animal physiology and I have nearly finished my diploma, yet. The topic of my thesis is about the morphology of neoptile feathers (first feather generation of chicks) in several bird species. I am mainly interested in the evolution of birds and theropods (sorry), but ornithischians are cool, too. Last year I visit China for an excavation in the Provence Xinjiang. For more information visit http://www.dinosaurhunter.org

Why did you decide to participate in the ODP?
I like open source, and when I read about your project, I was fascinated by the idea to create a public database for dinosaurs.

So far, what has been the best part of the ODP for you, and why?
I collected a lot of publications about paleontology (especially dinosaurs) since I was a 16. And finally, I have now a reason to use this stuff in a non-profit way.

What have you learned from your participation in the ODP?
First, internet and open science are cool. And second, I learned more about the anatomy of ornithischians, and I hope to learn more about locomotor system evolution in ornithischians.

What advice would you give those who might be interested in helping out with the ODP?
If you have a little time, literature or ornithischian dino bones which need measuring, join the club of ODP.

Categories: About Us, Interview

Can We Get A Hand?

September 23, 2009 12 comments

Or at least some measurements of hands? One of the things we’d love to do with the ODP data is investigate the way that the proportions of the fingers and toes, phalanges and unguals, metacarpals and metatarsals, changed through evolution. Do quadrupeds do something funky with their hands, and do they all do it in the same way?

For a little bit of data exploration, I decided to create a visualization of the proportions of the various bones making up the third digit of the hand. The third digit (which we know as the middle finger) is usually the central one in dinosaurs, or at least the longest one. Thus, it might be inferred to be most important functionally. The graph below shows the relative proportions of each phalanx and metacarpal in digit III, for a variety of dinosaurs. All have been scaled to the same length.

Relative Phalangeal Proportions of Manual Digit III ("The Middle Finger")

Relative Phalangeal Proportions of Manual Digit III ("The Middle Finger")

There are certainly some interesting patterns. First, the little ornithischian Heterodontosaurus and the saurischian Herrerasaurus (our outgroup comparison here) have very, very short metacarpals relative to the rest of the finger. Second, hadrosaurs (the duck-billed dinosaurs, including Kritosaurus, Parasaurolphus, and Corythosaurus) have really, really long metacarpals. Without exception, around 2/3 of their hand is metacarpal (equivalent to our palms). Note also that these hadrosaurs have lost phalanx four, and the penultimate (second-to-last) phalanx is really, really short. Ceratopsians (the horned dinosaurs, including Protoceratops, Styracosaurus, and Centrosaurus) and Hypsilophodon are somewhere in between.

How might I interpret this (cautiously, because we have so few data here)? Without a doubt, hadrosaurs are funky. Is this an adaptation for their unique brand of quadrupedality? Maybe. . .it would be nice to compare with more basal iguanodonts. I would like to say that the intermediate proportions of the ceratopsians (between Heterodontosaurus and hadrosaurs) are adaptations for quadrupedality, too, but the similar proportions of Hypsilophodon (usually assumed to be bipedal) add an unwelcome reality check on this hypothesis. Assuming that Heterodontosaurus and Herrerasaurus are both basal, perhaps we can interpret their digits as the ancestral condition for dinosaurs. These are interesting hypotheses, and ones that could be tested.

Unfortunately, we are running up against a problem with the goal of thoroughly documenting this aspect of ornithischian evolution: there just aren’t many measurements of fingers and toes out in the literature. I suspect the reason for this is two-fold: 1) fingers and toes were often the first thing to wash away prior to fossilization, or are so disarticulated that it’s impossible to identify which is which; and 2) authors present measurements for the humerus, radius, ulna, and sometimes metacarpal or metatarsal III, but don’t measure the rest of the limbs.

Conspicuously absent from the list: measurements of hands and feet for ankylosaurs, stegosaurs, basal ceratopsians (including psittacosaurs, for which there are literally dozens of articulated hands and feet!), and non-hadrosaurian ornithopods (with some many good, articulated iguanodont skeletons out there, you think someone would have published measurements). Even clades with a decent number of good hands and feet–such as hadrosaurs and ceratopsians–are missing measurements for many of the key specimens. So here’s your assignment: 1) if you have access to original material catalogued in public collections, spend a few minutes to measure some hands and feet, and send the data our way; and 2) if you have access to the literature, see what you can find for measurements there.

The ODP at SVP

September 21, 2009 4 comments
Small Logo

Have you been wanting to get together with other ODPers? Is all of this internet stuff getting you down, and are you craving human contact with other paleontologists on the project? Well, worry no longer – because the Open Dinosaur Project (or at least the Andy, Mike, and Matt section of ODP, and a number of volunteers and other supporters) will be at the Society of Vertebrate Paleontology meetings in Bristol this week!

If you want to find us, we’ll be walking around with our nametags, of course. Come on up and introduce yourselves (especially if we don’t know you already, or haven’t met you in person). We’ll also be wearing our t-shirts on at least one day, so we’ll be hard to miss. And finally, if you are really, really having trouble locating us, stop by our poster presentations. Andy (poster #25, on a new theropod from Madagascar) and Matt & Mike (poster #56, on the whole sauropod neck posture thing) will be in Poster Session IV on Saturday, from 4:15-6:15 pm, so come on over and say hi!

Our posting will be a little sparse over the coming week (aside from an auto-post or two), and we may be slow to respond to emails. . .if so, it’s because we’re having so much fun in Bristol! See you next week.

300

September 19, 2009 1 comment

No, I’m not talking about the recent cinematic adaptation of a graphic novel loosely based upon historical events. Better, even!

We passed 300 verified measurements this evening – in fact, we now have 307 verified entries, 83 unverified entries, and a scant four entries in the double-check list. Since the launch 10 days ago, we have increased the size of the verified database 6-fold. Excellent work, Team ODP!

Data Entry by ODP

It seems like just a few days ago when we had barely passed 150 entries.

Categories: Progress Reports

Update Your Spreadsheets!

September 18, 2009 Leave a comment
Manus of a hadrosaur (after Brown 1912)

Manus of a hadrosaur (after Brown 1912)

ODP contributor Christian Foth recently pointed out to me that the phalangeal counts for the manus as presented in the project data sheets needed to be expanded for derived ornithopods – I didn’t have enough columns for digit V! Alas, my efforts to force all dinosaurs to conform to the One True Phalangeal Count (that of ceratopsians, of course, with only V-1 and V-2, but no more) have been thwarted. I have updated the project spreadsheets as appropriate, with columns now for four manual phalanges on digit V. Thank you, Christian, for catching this problem!

Project contributors: make sure to download new copies of the spreadsheets ASAP – it makes my life easier when cutting and pasting data from your submissions.

Speaking of submissions, our data collection continues at a very nice pace. We have 247 verified entries, 100 unverified entries, and around 45 in the verification que that require minor corrections before posting to the verified list. That’s a whole pile of data.

Need something to do this weekend when you’re not typing in data? Head on over to Mike’s post on the perils of measuring specimens, and add to the discussion! Professional paleontologist or not, your thoughts are welcome. This is your project too!

Categories: Progress Reports Tags: , ,

Key Concepts: Osteology II (The Hindlimb)

September 17, 2009 3 comments

In a recent post, we gave an introduction to the osteology of the forelimb. Now, we’ll round out that series with a consideration of the hind limb. Fortunately, many of the concepts are the same, so we’ll be able to move more quickly.

As you may recall, the forelimb was divided into a pectoral girdle, a big proximal bone (the humerus), two more distal long bones (radius and ulna), and a hand (manus) consisting of some carpals, metacarpals, and phalanges (with some modified into unguals). The same pattern follows for the hind limb, with a pelvic girdle, a big proximal bone (the femur), two more distal long bones (tibia and fibula), and a foot (pes) consisting of some tarsals, metatarsals, and phalanges (again, with some modified into unguals). Easy, isn’t it?

Centrosaurus hind limb (after Brown 1917)

Centrosaurus hind limb (after Brown 1917)

First, let’s take a look at the pelvic girdle. In dinosaurs, as in humans and pretty much every other limbed vertebrate, the pelvis includes three elements on each side: ilium, pubis, and ischium. Looking at the whole structure in side view, the ilium is the top bone, and the latter two are on the bottom. Where the three bones meet, their surfaces form the limb socket, which is called the acetabulum. The ilium is a pretty big, usually flat structure, that anchors the pelvis (and thus the limb) to the vertebral column. Lots of thigh and butt muscles also attach to it. Of the two bottom bones, the pubis is the front (anterior, sometimes called cranial) one. A big deal has been made of its difference in its orientation between ornithischian and saurischian dinosaurs – in ornithischians, most of the bone is directed backwards, and in most saurischians (with the exception of birds and their close allies) the bone is directed forwards. Finally, there is the ischium (which a classically-grounded anatomy professor of mine liked to note is correctly pronounced with a hard “k” sound, rather than the “ish-ee-um” that most folks use). For various reasons (namely, all of the processes and extra bumps render accurate comparison of measurements difficult), we won’t be doing much with the pelvis in the present study. So, let’s move on to the femur.

The femur, just like the humerus, is a single robust bone that articulates with the limb girdle, its head fitting into the acetabulum proximally, and with two other elements distally. Sometimes, there is a little backwards-directed hangy process from the middle of the shaft, called the fourth trochanter.

The tibia and fibula are the developmental homologues of the forelimb’s radius and ulna. Unlike mammals, dinosaurs lack a kneecap (patella) floating over the proximal end of the tibia and distal end of the femur.

Centrosaurus pes (after Brown 1917)

Centrosaurus pes (after Brown 1917)

The “foot” is called the pes (Latin for “foot”), and is very slightly differently configured than for the manus. The hind limb’s equivalent of carpals are called tarsals – and unlike the condition up front, the tarsals are actually rather important and frequently ossified elements. In fact, they are so ossified that they usually fuse right on to the tibia and / or fibula. The two major tarsals in ornithischians are the astragalus (capping the tibia) and the calcaneum (capping the fibula, or at least floating in its general vicinity). Because the astragalus is so often fused to the tibia, many authors measure tibia length with the astragalus included.

Instead of metacarpals, we now have metatarsals. The numbering system is the same as for the manus, except they’re abbreviated as “MT.” So, the first (innermost) metatarsal, equivalent to the one associated with our big toe, is MT-I. Phalanges are handled quite similarly, with IV-2 being the second most proximal phalanx on the fourth digit. And once again, the final phalanges are often modified into unguals.

And that’s all there is to know about ornithischian dinosaur limb osteology!

Centrosaurus pes (after Brown 1917)

Centrosaurus pes (after Brown 1917)

Categories: Key Concepts Tags:

Developing a measurement protocol, part 1

September 16, 2009 13 comments

By now, those of you who have been entering data from the literature — and maybe even more those who have been measuring bones themselves — will have noticed that it’s not quite as straightforward as it sounds.  Some bones are crushed, distorted, broken, reconstructed, lost in soft peat for three months and recycled as firelighters.  And what exactly is the “length” of a curved bone like the femur of many ornithopods?  And where exactly is the “midshaft” that’s measured for the midshaft diameter?  And so on.

We want to develop an explicit protocol for what bones are worth including, what measurements need taking and how they should be taken.  But to do that, we’ll need your help.  We want to know what issues you’ve come up against as you’ve worked on ODP data, so we can figure out standard answers.  Post your questions as comments to this article: we’ll discuss them in the comments, and when we feel we have consensus, we’ll start to assemble a protocol document.

Our general feeling is that yes, there will be minor errors and distortions in the data, but there is no reason to suspect systematic bias and therefore not much to worry about (and not much we can do about it). Hopefully the database that we’re putting together will live forever and in the future people will revisit these specimens and submit “cleaned up” measurements in cases where that’s warranted. But that doesn’t mean we can’t be doing useful stuff in the meantime. It also doesn’t mean that we shouldn’t acknowledge these problems and fix them wherever possible.

So: (a) yes, crushing, distortion, reconstruction, measurement conventions, etc. are all valid concerns; (b) we will strive to overcome them to the extent possible, both immediately for the first paper and ultimately for the evolving database; but (c) these problems plague any large quantitative study of morphology — the only difference with the ODP is that those problems are out in the open; and (d) we don’t anticipate systematic bias and don’t think these problems are serious enough to prevent us from doing useful work right now.

Right then: questions, please!

Brachiosaurus altithorax holotype FMNH P25107, last three presacral vertebrae in right lateral view.  Sorry, I can't break the habit.

Brachiosaurus altithorax holotype FMNH P25107, last three presacral vertebrae in right lateral view. Sorry, I can't break the habit.

Categories: Basics, Tutorials

Status Report

September 16, 2009 17 comments

The ODP’s team members are amazing. Today we passed 200 verified entries – in fact, we rocketed past it to 228 verified entries! We’ve got 118 unverified entries, and ~45 that are in the que for final checking.

And now, a preliminary plot of femur length vs. tibia length (primarily ornithischians, with a few of the outgroup taxa thrown in). Want to make your own plots? Check out the publicly available data sheet!

Femur Length vs. Tibia Length

Log Femur Length vs. Log Tibia Length. Slope = 0.905, significantly different from 1.

Categories: Progress Reports

Key Concepts: Osteology I (The Forelimb)

September 15, 2009 16 comments
Forelimb of the horned dinosaur Centrosaurus apertus

Forelimb of the horned dinosaur Centrosaurus apertus

Osteology is the study of bones. Recognizing that not everyone here is completely familiar with all of the relevant names and features, this post will cover a brief tutorial of limb osteology and terminology in dinosaurs.

Broadly speaking, anatomists usually divide the skeleton into three sections: cranial (the head); axial (the vertebral column and ribs, although embryological and evolutionary histories mean that parts of the skull are sometimes lumped in here); and appendicular (the limbs). Presently, we’re only interested in the latter.

The appendicular skeleton includes forelimbs and hind limbs. Let’s start at the front in this post, and work back in a subsequent post. But before we start that, we need to introduce one more set of terms: proximal and distal (see image for their context within the forelimb). This just refers to the position along a structure relative to the main part of the body. Proximal is close to the body, and distal is away from it. Considering the humerus (upper arm bone), the elbow is at the distal end and the shoulder is at the proximal end. Within the entire leg, your toes are at the distal end and the thigh bone is at the proximal end.

The forelimb includes the pectoral girdle as well as the limb bones themselves. In dinosaurs, the pectoral girdle includes a scapula, a coracoid and a sternal plate on each side. Humans have scapulae too (most of us know them as “shoulder blades”), but our coracoids have shrunk down to little nubbins (the coracoid processes) that are fused onto the scapulae themselves. We also have clavicles (“collar bones”) as part of our pectoral girdle, but ornithischians lack this bone (although theropods preserve part of it in the furcula, or “wishbone”). In all adult ornithischians, the scapula and coracoid are fused together, and the area where they meet forms the glenoid, or shoulder socket. If the bones are fused, their total combination is then called a “scapulocoracoid.”

The humerus (or “upper arm bone”) fits into the glenoid. It’s a long bone, expanded at both ends for various muscle and bony attachments. Lots of muscles—including the famous deltoids, lats, biceps, triceps, and pectoral muscles—attach here. The “midshaft” of the humerus is exactly that – the point at the middle of bone.

A pair of bones – the ulna and radius – form the forearm. They articulate with the distal end of the humerus. They’re pretty simple, rod-like bones in most cases. The ulna usually has a process (i.e. a sticking-out bit), called the olecranon, at its proximal end for attachment of the triceps muscle.

Finally, we have the hand – more properly called the manus (Latin for “hand,” strangely enough). The manus has carpals (wrist bones), metacarpals (joining the wrist to the digits), and phalanges. Each digit (or finger) is numbered starting at the thumb. The thumb (innermost digit, for ornithischians) is I (note the Roman numeral), the index finger II, middle finger III, ring finger IV, and pinkie V.

The most proximal elements within the manus (just distal to the ulna and radius) are called the carpals. They’re often just cartilage, and even when ossified are rarely preserved (they tend to float away if the skeleton becomes disarticulated). At any rate, they’re usually non-descript little round elements in ornithischians, and we’ll pretend these bones don’t exist for the purposes of our study.

Manus of the horned dinosaur Centrosaurus (modified after Brown 1917)

Right manus of the horned dinosaur Centrosaurus (modified after Brown 1917)

Next, we have the metacarpals. If you squeeze the palm of your right hand between the thumb and index finger of your left, these are the bones you’re feeling. The number of metacarpals is variable in many dinosaurs. Humans, and most ornithischians, have five metacarpals (and hence, five fingers in most cases). Most theropods have fewer. “Metacarpal” is often abbreviated as MC. So, the first metacarpal would be MC-I, and so on.

Finally, we come to the phalanges. A single element is most properly called a phalanx (not a “phalange,” although this archaic spelling is not technically incorrect – many older publications use the terminology). The phalanges are numbered by digit (I-V) as well as their position relative to the metacarpals (given by an Arabic numeral). For instance, I-1 is the first phalanx on the first digit, and III-2 is the second phalanx on the third digit. The second-to-last phalanx is sometimes referred to as the “penultimate” phalanx.

The distal-most (terminal) phalanx is often modified into a hoof or claw. These specially modified phalanges are usually called unguals, but they are numbered just the same as regular phalanges. Even if the third and final phalanx on the third digit is a huge claw, it’s still called manual phalanx III-3.

Finally, we should mention the sternal plates. These odd bones (probably equivalent to the sternum, or breast bone, of mammals) are usually floating at the front of the chest wall. The sternals sometimes look like kidney beans (in ceratopsids) or hatchets (in other ornithischians).

It’s a blizzard of terms, but a little practice should help you become completely conversant with all of the parts of the forelimb. In an upcoming post, we’ll tackle the hindlimb. Don’t worry – many of the concepts are the same!

Categories: Key Concepts, Tutorials Tags:
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