Thursday, September 29, 2011

You can pick your friends, and you can pick your nose...and you can definitely pick your ankylosaur's nose.


Say hello to Euoplocephalus, the best known ankylosaur you've never heard of. Besides Pinacosaurus from Mongolia and China, there are more specimens referred to Euoplocephalus than to any other ankylosaurid, and it is certainly the most well represented ankylosaurid from North America. Yet Euoplocephalus often gets overlooked because its younger cousin is THAT ankylosaur, the one that starred at the World's Fair and was in Jurassic Park III and Clash of the Dinosaurs and Dinosaur Revolution and gets all the cool toys and, you know, is the namesake of the group. You know, Ankylosaurus. Well, hopefully you'll be hearing more from me about Euoplocephalus over the coming months. Today we'll be picking its nose.

Ankylosaurs are kind of weird as dinosaurs goes, because they get rid of things like the antorbital and supraorbital fenestrae, and tuck the laterotemporal fenestrae back behind the squamosals and quadratojugals. In a sense, the windows to the skull are all closed, and so it's hard to see some of the internal features that are more visible on other dinosaur skulls. Our new paper describes UALVP 47977, a busted up Euoplocephalus skull from Dinosaur Provincial Park. Normally, busted skulls don't appear very exciting, as important pieces might be missing, and they don't make very good display specimens. In this case however, UALVP 47977 gives us more information because it is broken! This specimen shows off details of the braincase and nasal passages that we don't typically get to see, including impressions of blood vessels.

I am trying (slowly but surely) to sort out the mess that is the genus Euoplocephalus, and so I was interested in comparing UALVP 47977 with other skulls to see if any of its features were present in other skulls. The only other skull that is naturally broken in a similar way is AMNH 5238, and it looks pretty similar - it even has blood vessel impressions in the same place (this specimen is also super cool because it has ciliary osteoderms, or, bony eyelids!). I was delighted when Dr. Larry Witmer made the CT scans of AMNH 5405 available on his website following the Witmer and Ridgely (2008) publication on paranasal sinuses. I also made arrangments to CT scan UALVP 31, one of our 'classic' University of Alberta specimens.

With CT scans in hand, I went through the process of eliminating matrix from the inside of the nasal passages (in essence, picking their noses), so I could examine the skull roof of these two specimens. This process is called segmentation, which means that you place a 'mask' over the parts of the CT scan that you want to appear in the 3D model, and remove the mask where you don't want something in the model. Although the software we use, Mimics, has lots of tools to help speed up the segmentation process, with fossils sometimes the contrast between bone and stone is not very great. As a result, sometimes you just have to go through the CT scans slice by slice and trace out by hand what you want to keep. This is super tedious work at times and I have the utmost respect for the amazing 3D visualizations that come out of Dr. Witmer's lab. Eventually we invited Dr. Witmer to collaborate on the paper with us, but I think it was good that we were able to independently test their 3D model using different software and fresh eyes, a sentiment echoed over on the WitmerLab blog.


The segmentation process begins! All of that uniformly-dense stuff in the palatal area has to go. The green 'mask' will be eliminated wherever there is matrix instead of bone, leaving only the bone in the 3D model.

I won't go into too much detail on the paper here, but I will say that this was a tough but very interesting project to work on. I've learned a lot about braincases and brains and noses over the course of writing this manuscript, but I'm sure I've still got more to learn. I've definitely had a lot of moments where I felt pretty stupid for not knowing certain things, but I think perhaps part of science is getting outside of your comfort zone. Ankylosaur tails are good, but skulls are pretty fun too, and I hope I can share some more skull papers with you soon! 

Here's a video we put together for the press release accompanying the paper, featuring the ever lovely UALVP 31.

video


Literature!

Miyashita T, Arbour VM, Witmer LM, Currie PJ. 2011. The internal cranial morphology of an armoured dinosaur Euoplocephalus corroborated by X-ray computed tomographic reconstruction. Journal of Anatomy, first published 29 Sept 2011, doi:10.111/j.1469.-7580.2011.01427.x.


And check out the post over at Pick & Scalpel, which has more information and some great images!




...and finally, because this has certainly helped me sometimes:
Schwartz MA. 2008. The importance of stupidity in scientific research. Journal of Cell science 121:1771.

Sunday, September 25, 2011

Hadrosaurs get their moment in the sun.

Living in Edmonton means I'm in close proximity to the dinosaur capital of Canada, Drumheller, and the wonderful Royal Tyrrell Museum. Last week the U of A crew headed down to the Hadrosaur Symposium, a wonderful event by all accounts with lots of interesting talks and good conversation. I won't report on the science presented as much of the research is as yet unpublished (although look out for the eventual symposium volume), but thought I would share a few photos and links to symposium goodies.

First off, the Tyrrell is making some of the keynote lectures available on their Youtube channel. David Weishampel's is already online; other keynote speakers were Kishigjav Tsogtbaatar, Pascale Godefroit, Rodolfo Coria, and Jack Horner.


You can also check out the official Hadrosaur Symposium Flickr page for some very nice photos of the goings on.

And here's a few photos of my own!


Symposium attendees get a backstage tour of the collections.


Hadrosaur heads in the main gallery.


And some hadrosaur bodies!


There were some original skulls on display in the poster room as well.

Tuesday, September 20, 2011

I'm a Palaeontologist, and I liked Dinosaur Revolution.

There. I said it. I liked Dinosaur Revolution.



I was pretty sure I'd be hooked from the moment I saw the trailer and saw this recreated with Cryolophosaurus. Hot dang, the raging dino fanboy in me loves me some Charles Knight.

I have been following with great interest the various perspectives on Dinosaur Revolution at palaeoblogs around the net - see Love in the Time of Chasmosaurs, Dinosaur Tracking, and a whole slew of posts over on Art Evolved. As with any dino documentary (and probably ALL documentaries, regardless of subject matter), there are inaccuracies to point out. However, I was surprised by strong backlash Dinosaur Revolution has seemed to receive around the palaeo blogosphere. I've only caught the first two episodes so far, but I'm looking forward to seeing the next two.



I view Dinosaur Revolution as kind of like an animated children's storybook about dinosaurs - something like the A Day in the Life of... series, which has a story followed by a discussion of the scientific research behind the story. Would we criticize a children's storybook for using narrative and some anthropomorphism to get the story across? Or how about, would we criticize it based on its art style - cartoons get a pass (the I Am A... series), but more photorealistic portrayals don't?

I think the show does a pretty good job of getting some science across within the context of what the show is supposed to be. The short interstitials with the palaeontologists provide a bit of context for some of the ideas being presented, there's footage of fossils and fieldwork, and there's even AN EXPERIMENT! at the end of The Watering Hole. I agree with many reviews that the second episode was the stronger of the first two, and that the first episode was somewhat uneven. I didn't love every part of Dinosaur Revolution, but I liked more than I disliked. I disliked Gigantoraptor's crazy inflatable wattle, but not because it was crazy - I disliked it because it took away from the potentially more interesting story about display feathers in oviraptorosaurs. I disliked Saurosuchus not eating the Eoraptor that it bit and threw away, because that was crazy. But I liked a lot of the (I guess) controversial bits - the Looney Tunes homages, the therapsid getting thrown into the Saurosuchus' mouth, the Glacialisaurus hacking up a wad of sap. Those things were funny, and I think in the context of this particular program that the humour worked well and was ok.

And seriously, how cool is it to have the Ischigualasto, the Hanson, and the Iren Dabasu formations all in one episode? Have we ever seen Eoraptor, Glacialisaurus, or Gigantoraptor on TV before? I hope that the portrayal of all these marvelous dinosaurs inspires people to head to Wikipedia and learn more.

So I'm wondering - a lot of the controversial things in Dinosaur Revolution seem, well, cool to me. And I think it's ok to be cool. And I think that Dinosaur Revolution was marketed to be cool, and to be more storybook, less documentary sensu stricto. They advertised it at Comic Con! How often do dino documentaries get advertised at geek conventions?


That Tyrannosaurus has a skull for a face, and that is cool. He's like Ghost Rider!

So I liked Dinosaur Revolution, and I think it's a shame more people didn't. Perhaps context is everything. Perhaps the biggest problem is that even though the marketing indicated this was not a typical documentary, airing this on the Discovery and Science Channels was just the wrong context.

Thursday, September 1, 2011

Velociraptor-free, mostly...


For the last several years, our lab has run a volunteer fossil prep program on weekday evenings. As the school year starts again, I thought I'd share our recruitment poster for this year!




We are very fortunate to have two prep labs in the BioSci building at the University of Alberta. Our basement lab handles the larger, more complex specimens like skulls or partial skeletons. The fourth floor lab, shown here, is where volunteers help us get through the enormous quantity of smaller fossils we've collected. There's lots of table space and light, and with volunteers it becomes quite sociable in the evenings!



There's always at least one grad student or upper-year undergrad present who supervises the volunteers and teaches them prep techniques. Volunteers have come from many different departments at the U of A, not just the sciences! We also get the occasional volunteers from outside the university, who hear about us online or via posters we put up around town.



Volunteers help us prepare a wide variety of material from all over Alberta, including theropods, hadrosaurs, ceratopsians, crocs, turtles, and champsosaurs. A lot of the small material comes from Dinosaur Provincial Park and is fairly easy to prep (sometimes just require a good toothbrushing and some glue!), but we also have more challenging projects like specimens from our Wapiti River Pachyrhinosaurus bonebed in Grande Prairie. We also have material collected way back in 1921 that has never been prepared!

The beginning of the school year is always exciting and I hope we'll see a bunch of new and returning volunteers in the next few weeks. If you're interested in keeping up with the goings on in our lab, you can follow us on our Facebook page, Dino Lab at the University of Alberta.