Wednesday, June 30, 2010

Sauropods and Megapodes

Rabaul and the vulcano Tavurvur
Megapode eggs in volcanically heated sand on Papua New Guinea. Photo by Rita Willaert, via flickr.

Sometimes, an idea is too good not to be repeated. Some members of the family of modern birds called megapodes have found volcanically heated ground quite suitable for incubating their eggs. It turns out that at least some sauropods had the same idea.

Reporting their findings in Nature, paleontologists Gerald Grellet-Tinner and Lucas E. Fiorelli have determined that an unidentified species of large sauropod established a nesting ground in a geothermal area in Cretaceous Argentina. The geological signature is unmistakeable, bearing minerals that are known to occur at modern geothermal areas, as well as the remains of stromatolites, the algal mats that produce the fantastic array of colors that draw crowds of tourists to hot springs and geysers. Grellet-Tinner and Fiorelli note that this area seems to have been the Cretaceous equivalent of Yellowstone's Norris Geyer Basin, home of the Steamboat Geyser. The moisture of the soil and its temperature of about 80 °C would have created ideal conditions for the eggs to incubate. All egg clutches were found within three meters of geyser vents.

This discovery sheds important light on the nesting habits of sauropods and further fleshes out the relationships between dinosaurs and their environments that allow us to reconstruct Mesozoic ecology. Grellet-Tinner and Fiorelli suggest that next, paleontologists should examine other known nesting sites to determine if geothermal activity was a major factor in where sauropods chose to lay their eggs.

More on sauropods: Archosaur Musings features a guest post from Peter Falkingham discussing his new research which provides a nice explanation for why many sauropod trackways only provide prints from the forelimbs.

Tuesday, June 29, 2010

Down the Red Deer River

Today, we wish the members of the Dinosaur Hunting By Boat expedition the best of luck as they launch their recreation of the AMNH scow boat Mary Jane. The expedition has been planned to accurately reflect the tools and living conditions experienced by the paleontologists and support staff during a series of fossil-hunting on the Red Deer River in Alberta, occuring between 1910 and 1914. This project is the brainchild of paleontologist Darren Tanke of the Royal Tyrrell Museum (I previously wrote about it in November).

This is going to be a heck of an experience. I'm envious. Here are some photos of the gorgeous landscape they'll be treated to during the journey. All come from Flickr, photographers credited below.

red deer river valley
Sean Birch

None but the brave deserve the flare
Ken Langevin

Along The Red Deer
Trevor & Rachel

Red Deer River near Drumheller
G Dakin

Monday, June 28, 2010

High Fashion Dromaeosaur

Wikipedia's article on cufflinks says that the fashion accessories, which have been around in their modern form since the early 18th century, come in "numerous styles including novelty cufflinks, traditional cufflinks, contemporary cufflinks, utility cufflinks, and humorous cufflinks." Add bad-ass cufflinks to that list. Etsy seller Giant Eye, who describes himself as "somewhere in between an artist turned engineer and a designer turned adventurer," is hooking dinosaur enthusiasts up with this classy set of cufflinks.

Mini Raptor Cufflinks

Prepare for your next fancy dress event by purchasing them here. There's a larger set, cut in the shape of the little theropod available here, and something for the ladies right about here. Much gratitude flows in the general direction of my intrepid spouse, who spotted these handsome little guys.

Friday, June 25, 2010

Vintage Dinosaur Art: John Hamberger's Sea Monsters

For the last couple months, Jennie and I have been working our way through the entire run of The X-Files. It was one of my favorite shows when I was a teenager, and I was curious about how it would hold up. At the time, I was a Mulder: listening to Coast to Coast AM with Art Bell, writing school papers about UFO cover-ups, bitterly wondering why I never saw a flying saucer of my own. Now, I'm a Scully. Would the show still hold up now that I'm not sympathetic to its paranormal-friendly premise?

For the most part, it does, mostly on the strength of Mulder and Scully's relationship. But now I can see how much it uses science as a punching bag. Scully's tendency to get kidnapped and tied up metaphorically illustrates Chris Carter and the gangs' attitude towards science: they're good at throwing jargony dialogue at the audience, but it often betrays their disinterest in depicting science accurately (they can't, of course: in the fictional world of the X-Files, no form of woo-woo is too nutty to be real). Case in point: one of my favorite episode's, season three's "Quagmire," actually has Scully calling the supposed lake monster Mulder is hunting an "aquatic dinosaur." That's just not a mistake Scully would make. She should know better.

Mulder actually theorizes that "Big Blue," the lake monster he's chasing, is a pliosaur. The writers may have meant "plesiosaur," as that's such a common diagnosis for the Loch Ness Monster - and when Big Blue makes an appearance at the very end of the episode, that's what its clearly been based on. But had they gone with a pliosaur, it would have been a pretty cool and unique choice.

What's a pliosaur? It's a family within the order Plesiosauria; it includes such notable beasts as Liopleurodon and Kronosaurus. Here, a Kronosaurus hunts a smaller plesiosaur.

Page18-19

This image is taken from Sea Monsters of Long Ago, another Millicent E. Selsam title. It's full of striking paintings by John Hamberger. Huge thanks go to Matt Van Rooijen for letting me know about this title, and uploading it to the Vintage Dinosaur Art flickr pool.

Cover

I haven't been able to dig up much information on Hamberger, but it appears that he has done at least one dinosaur book. Many of the titles associated with him are nature books, so I imagine that was his special interest. Like the one below, many of the images in Sea Monsters are dramatically composed, depicting the giant marine reptiles as gods who made the sea their playground.

Page16-17

Here, a Tylosaurus is about to make breakfast out of a Hesperornis.
Page20-21

Icthyosaurs like Opthalmosaurus also get the spotlight.
Page12

If you know any more about Mr. Hamberger, please share it in the comments below. I haven't found anything about him, not even a single mention on any of the illustration blogs I follow. Thanks again to Matt for adding these to the group. If you have any old dinosaur books lying around, feel free to scan them and upload them so these illustrators aren't lost in the shadows.

Thursday, June 24, 2010

Dan Telfer on "The Best Dinosaur"

My bud Joey hipped me to this comedian dude's comedy act. This is a bit called "The Best Dinosaur." You can watch it right here, but fair warning: the language gets a wee salty.



This has been doing that viral thing over the last few days, partly because nerd-folk are thrilled that a stand up comic knows so much about dinosaurs. He refers to obscure dinosaurs as "deep cuts!" Why, he even knows that pterosaurs and plesiosaurs aren't dinosaurs! As BoingBoing says "Pedantry can be fun!"

The problem? He totally whiffs on a bunch of facts. It's a good bit, really: it takes the scenic route through the Mesozoic to make a self-deprecating joke about how much of a wuss he is. Blogger Elizabeth McQuern, one of Telfer's buds, says that she's been watching as he's refined this joke, and feels it's reached its apex. But brother, you'd better not bring it to the SVP meeting this year. Not in this state. You need to get some facts straight. So I'm going to do you a solid. In other words: you want pedantry, BoingBoing? I got your pedantry right here.

First. T. rex and Giganotosaurus are most certainly not in the same genus. Giganotosaurus isn't even a coelurosaur. So, not particularly closely related.

Second. Spinosaurus was a big dude, no doubt. Could he have mauled anything on the planet? Maybe, when push came to shove. But would he? He was a fish eater. I'd aim your joke in that direction.

Third. Stegosaurus ain't got no "ass brain." Sorry, bro. That's been debunked, and how. And a brain in its stomach? Come on. that's even wronger than wrong.

Fourth. Brontosaurus wasn't a Stegosaurus skull on an Apatosaurus body. It was a mishmash of parts from Camarasaurus skulls. Just say that it had the wrong head.

Fifth. Velociraptor's genus wasn't "raptor." Dude, come on! this is like, fundamental taxonomy! Genus. Species. Velociraptor's genus was... Velociraptor! DUDE COME ON!

Sixth. Brachiosaurus. Ultrasaurus. See previous.

Solve those problems, and it's all good loving. Also, read Monster Isle by the aforementioned Joey!

UPDATE: Telfer explains the joke here and has been defended by Carl Zimmer against "paleo-fact-checkers." I had no idea that it had kicked up such a storm; I figured this little obscure post would be somewhat unique. Once again, I've misunderestimated the cyber-hive.

So I figured I may as well clear a bit up, too. First, that this post itself is a joke. Pedants are much more fun to poke fun at than the people they're correcting, after all. Second, Telfer could have avoided being bombarded by nerd emails by changing a few words in the routine. Like I said, I like the bit. But the good part isn't that he gets stuff wrong.

Ugh. Put a gun to my head.

UPDATE 2: As of March 2011, this humble little post is within the first ten results when "Dan Telfer" is googled. I just want to reiterate that this post was a ham-handed joke. Telfer seems to be a good dude. He's a funny Tweeter. And I kind of hate that this dumb post might be seen as one more jerk piling on the guy. So I'll do what I can and recommend that you purchase his comedy album, Fossil Record. It's also available as a triple-pack, with sets from the reliably funny Paul F. Tomkins and Greg Proops. Yeah, THAT Greg Proops! The guy who did the voice for the two-headed podrace announcer in The Phantom Menace! Savvy?

Falcarius, Clarified

I'm not even going to try to make excuses. This paper has been sitting on my desktop since January because I forgot about it. I found it this morning when I executed a sorely needed declutterization operation. So, six months after it was published by the Linnaean Society, I'm going to write about paleontologist Lindsay Zanno's detailed description of the therizinosaur Falcarius. Like Jell-O desserts, there's always room for therizinosaurs.


Falcarius, by Michael Skrepnick. From the University of Utah via NatGeo.

I've written about the therizinosaurs before, because they're some of my favorite dinosaurs: fiercely clawed feathered theropods who've gone vegetarian, some of whom grew to huge sizes. They're primarily known from Asia; North America joined the club in the early 2000's with the discovery of late Cretaceous Nothronychus in New Mexico. Soon afterwards, Falcarius was discovered in Utah, and was found to be contemporaneous with the then-earliest known therizinosaur, China's early Cretaceous Beipiaosaurus. As Zanno notes in her analysis, Falcarius differs from Beipiaosaurus in lacking many of its more derived features - those that would be further refined and emphasized by their ancestors. It's an evolutionary puzzle: why is Falcarius so primitive compared to its Chinese contemporary? Zanno puts forward three hypotheses that will require new discoveries or research to clear up:
  1. Better dating of the sediments in which the two therizinosaurs were found could reveal that Falcarius is actually a bit older.
  2. Environmental factors in Asia may have favored therizinosaurs there to evolve at a faster rate than their North American relatives.
  3. Falcarius shared North America with other therizinosaurs more similar to Beipiaosaurus, which haven't been found yet.
One of Falcarius' distinguishing features is its teeth. Like primitive relatives of the oviraptorosaurs, which also evolved toothless beaks, Falcarius had relatively large teeth in the front of its jaws. It's likely due to the therizinosaurs' shift from carnivory to omnivory and then herbivory (that last step isn't necessarily where the oviraptorosaurs settled). What's interesting is that a herbivorous diet required the suite of anatomical adjustments that make the later therizinosaurs so unique - large guts to breakdown nutrient-stingy plant material, wider pelvises, stouter legs. Falcarius shows some initial steps toward those features, probably necessary to compete in North American ecosystems with the dromaeosaurs and tyrannosaurs who dominated predatory niches. As Zanno says in her conclusion, we're going to need some serious functional studies of the skeletons of derived therizinosaurs to really determine how they lived and moved, and this in-depth look at Falcarius provides a "baseline" for that work.

Of course, maybe an apparently advanced therizinosaur from the Jurassic will be discovered in Australia and turn the world upside down. That could happen, too.

Wednesday, June 23, 2010

Hold Your Head High, Brachiosaurus

One of the recent debates in paleontology has concerned the neck posture of the sauropods. Such titanic creatures are completely absent from land today, so it's natural for them to be puzzled over.

Walking With Dinosaurs, the 1999 documentary, featured herds of Diplodocus with their heads held basically parallel to the ground, reflecting some paleontologists' supposition that for the beasts to raise them much higher would have been an unbearable strain, requiring blood pressure too high for their hearts to bear. The SV-POW! team has weighed in with a strong argument to the contrary, based on the evidence provided by living animals - a fantastic summary is available here. Rather than a straight horizontal line, they argue that it made more sense for sauropods like Diplodocus and Apatosaurus to hold their heads at a gentle curve, with the heads well above their bodies.

Examining the Chinese early Cretaceous sauropod Euhelopus, Andreas Christian from the University of Flensberg has concluded that it was especially adapted for high browsing, a conclusion that likely bears true for similar sauropods, notably the ever-popular Brachiosaurus.


Euhelopus, via wikimedia commons.

As you can see in the above reconstruction, Euhelopus is similar to Brachiosaurus in its marked differences from the standard-issue, Flintstones-style "brontosaur." The front legs are longer than the back, and the tail is shorter. In all, the profile is more giraffe-like. Christian's paper suggests that this posture, while requiring considerable effort to pump blood up through the neck, was less expensive than grazing over a broader area - holding its head at a 90 degree angle from the horizontal for five minutes required only about half of the energy expenditure as walking a hundred meters. He also found that the stresses on the neck vertebra were lower in as Euhelopus held its neck more erect. Christian concludes that "raising the neck... may have been less expensive for a sauropod like Euhelopus or Brachiosaurus than walking a long distance. During a food shortage, raising the neck was probably even essential for surviving: it is better to get little than nothing at all." Not an earth-shattering discovery, but one that adds to our understanding of how such a magnificent adaptation made sense for these animals.

Tuesday, June 22, 2010

Yoshied

Threadless Weekly hasn't featured much mesozoica lately, but here's a great reimagining of Mario, the Princess, Yoshi, and a Koopa Paratroopa by Vincent Bocognani.

historical reconstitution

Here's similar take on Yoshi, which Bocognani did earlier this year.

yoshi revenge

I especially love the fact (in a morbid way) that the brothers Mario were so close to a patch of life-granting green mushrooms. More of Bocognani's illustrations here and here.

Monday, June 21, 2010

The London Pterosaurs Arrive

Over at the Pterosaur.net blog, Mark Witton reports that the moment of truth has arrived: the Dragons of the Air exhibition in London goes up this week. It should be a great PR boost for the pterosaurs, and hopefully at least a few people will have the assumption that they're just funny-looking flying dinosaurs struck from their heads. The exhibition includes enormous life-size azhdarchids strung between buildings, which would be pretty awesome to stumble upon while out on a stroll.

The exhibition is part of the See Further Festival, celebrating the 35oth anniversary of the Royal Society. The Royal Society is also providing open access to its archives until July 30, 2010. There are nearly 70,000 papers available covering the entire 350 years. It's like standing in front of a geological exposure that preserves everything from the Cambrian to the Miocene.

If only airfare to the UK hadn't doubled since a year ago...



Friday, June 18, 2010

Vintage Dinosaur Art: Harriett Springer

The "First Look" series of books were written by Millicent E. Selsam with occasional coauthors. Harriett Springer provided the illustrations for a number of the titles in the series, including 1982's A First Look at Dinosaurs.

A First Look at Dinosaurs
Whoever first owned this book had a case of the scribblies.

Theropod Line-up
A line up of theropods.

Duckbill Heads
Duckbill headshots.

Stegosaurus and Kentrosaurus
Spot the typo!

I haven't been able to find any good information about Springer, though according to the above link Selsam worked with Asimov on his "How Did We Find Out" series of science texts for young readers. The only one of those titles I've found is How Did We Find Out About Atoms?. I'm keeping my eyes peeled for the dinosaur entry in the series.

Thursday, June 17, 2010

Serendipaceratops, Again

It's been a week since I last wrote about Serendipaceratops, a glaring problem I'll now correct. A refresher: Serendipaceratops arthurcclarkei is a dinosaur named by Australian paleontologists Mark Rich and Patricia Vickers-Rich based on a single ulna. After seeing a Leptoceratops ulna shown to them by Canadian paleontologist Dale Russell, they decided it represented a neoceratopsian - living tens of millions of years before the other neoceratopsians and really far away from the family's predominant territory of Asia.

As luck would have it, on May 22, 2010, Argentinian Museum of Natural Sciences paleontologists Federico L. Agnolin, Martin D. Ezcurra and Diego F. Pais, joined by Steven W. Salisbury of the University of Queensland, published a sweeping reappraisal of the Mesozoic fauna of Australia and New Zealand. Huge thanks to commenter Jay, who tipped me off to this. I have been able to get a copy of the paper and took a look at it. It's been the subject of debate surrounding nomina dubia, "dubious names." Basically, it works like this: Paleontologist A describes a fossil and decides that it's unique and thus warrants the naming of a new species. Then, paleontologists B through K look at the specimen and decide that the fossil isn't actually that unique, or more associated fossils are needed to make the determination. Paleontologist A's name for the fossil is then considered a nomen dubium. Mickey Mortimer's Theropod Database Blog and Jamie Headdon's The Bite Stuff each have posts discussing their respective opinions on the topic.

As Jay said in his comment, Agnolin et al suggest that Serendipaceratops is probably not a ceratopsian, and cannot be confidently assigned beyond being an indeterminate Genasaurian. The clade Genasauria is a large group that includes the ceratopsians, the ornithopods (Iguanodon, the duck-bills, and their kin), the stegosaurs, and armored dinosaurs like Ankylosaurus and Edmontonia. Almost all ornithischian dinosaurs, except for a handful of the most primitive ones, fall under its umbrella.


The Australian ankylosaur Minmi, by Mariana Ruiz, via Wikimedia Commons.

The authors argue that Serendipaceratops simply doesn't have adequate fossil evidence to draw any strong conclusions as to what kind of critter it was, though they do note that "...the proportions of the ulna of Serendipaceratops are closer to Minmi sp. and other ankylosaurians than to any neoceratopsian." Thus, they decide that Serendipaceratops arthurcclarkei is a nomen dubium.

In the chance that Agnolin and his crew's ideas are borne out, it may be a good idea to horde some Serendipaceratops keychains.

Wednesday, June 16, 2010

Dinosaurs of Scotland

The Highlands
Entering the Cairngorms. Photo by yours truly.

I've got a huge travelin' jones. My wife and I are constantly planning a trip, sometimes before the current one has ended. One of my favorite countries to visit is Scotland, which we drove through for a few days in 2008, looping from Edinburgh up through the highlands around to Loch Lomond, somehow emerging with our marriage intact despite my often fried mental state as I tried to adjust to driving on the "other" side of the road. I really can't wait to get back and backpack across the Cairngorms, visit the Hebrides, and spend some time among the islands of the Atlantic coast.

Scotland has a proud geological tradition, populated by such important figures as the father of modern geology, James Hutton, and Sir Roderick Murchison. And it's a land intimately connected with some of my favorite landscapes here in the states: the highlands were once connected to the Appalachians, both born during the Caledonian orogeny as Pangaea formed. Scotland has a diverse geology, and the mesozoic gets a bit of space, too: the famed Isle of Skye is a slice of the Jurassic.

The Hunterian Museum's website features a summary of dinosaur discoveries on the Isle of Skye. What's been found doesn't amount to much, but it's enough to roughly sketch out a segment of Scotland's Jurassic fauna. The Hunterian's curator of paleontology, Neil Clark, also provided an overview of the subject in a 2007 Deposits Magazine article, available as a free PDF from the University of Glasgow. He talks about the trackway discovered in the 90's which may preserve the footprints of a group of hatchling theropods accompanied by an adult - though speculating about trackways is a notoriously shaky endeavor. He believes that another set represents the smallest dinosaur footprints ever found, made by a tiny hatchling that wouldn't have been much larger than something you'd see in your birdbath.

"Dougie" the cetiosaur, by Neil Clark.

Most prominent is a humerus believed to belong to a member of the cetiosaur family of sauropods. The cetiosaurs are a primitive group named for Cetiosaurus, the first sauropod discovered - so early that it was named by Sir Richard Owen before he'd even coined the word "dinosaur." The great anatomist believed it belonged to a sea creature, and its dinosaurian identity was finally discerned by T.H. Huxley in 1869. Though the Scottish cetiosaur hasn't been assigned to a sauropod taxa, it has been graced with the nickname "Dougie." I'd wager that the namesake is Dugald "Dougie" Ross, curator of the Isle of Skye's Staffin Museum, which has just become a definite must-see next time I'm across the Atlantic.

Monday, June 14, 2010

Warm-Blooded Sea Monsters of the Mesozoic

Plesiosaurus
Origami Plesiosaurus by Oriholic Jared, via Flickr.

A new study published in Science suggests that the great predators of Mesozoic seas, the plesiosaurs, icthyosaurs, and mosasaurs, maintained an average body temperature around 100 degrees Fahrenheit. This conclusion was achieved by studying the oxygen isotopes in their teeth; fish from the mesozoic and today - all cold-blooded, of course - show variation in their oxygen isotopes based on the temperature of water they live in. The marine reptiles of the Mesozoic don't show this variation. No matter what temperature water they lived in, they maintained a constant temperature and thus can be assumed to have been active predators adept at cornering the apex predator niche in all sorts of marine environments.

It's important to note that this doesn't directly relate to the metabolism of dinosaurs, which were distant cousins of the aquatic reptiles. But it is another demonstration that the "slow, sluggish, cold-blooded" baggage associated with the word "reptile" only hides the stunning diversity of adaptations these critters have employed over their hundreds of millions of years on Earth.

Friday, June 11, 2010

Vintage Dinosaur Art: Tim and Greg Hildebrandt

The Brothers Hildebrandt, Tim and Greg, are illustrating legends, and I was heavily stoked when I came across this title at a resale shop, stuffed unceremoniously between two lesser books. Pinup girls, Darth Vader, hobbits, and Hollywood monsters have been brought to life in their unmistakable style, so it's only fitting that the greatest creatures to ever walk the Earth should as well. Titled simply Dinosaurs, it was published by Merrigold Press in 1976.

Merrigold Press Dinosaurs

Dig these hairy Pteranodons, buzzing a Pachycephalosaurus. A bonus ChasmoPointTM for not calling them dinosaurs!

Hildebrandt Pteranodons

Even the Hildebrandts weren't immune to copping a bit of Charles M. Knight's portfolio, though. Witness the latest installment in the Ornitholestes library I'm slowly amassing.

Hildebrandt Ornitholestes

It may look like a man in a suit, but this version of the tyrant king is total evil.

Hildebrandt Tyrannosaurus

I would like to see a post-renaissance take on dinosaurs from the Hildebrandts - maybe a pulpy, lurid series on Jurassic Park. Something like they did with the original Star Wars poster, you know the one with Luke raising his lightsaber above his head and Leia striking a pose at his feet. Only substitute in Alan Grant and Ellie Sattler, with T. rex instead of Darth Vader. I bet their take on the ice cream eating scene would be mind-blowing.

Thursday, June 10, 2010

Further Musings on Serendipaceratops

One of the scientists in the media I've come to trust and respect is Steven Novella, the neurologist who co-founded the New England Skeptical Society, hosts The Skeptic's Guide to the Universe podcast, and blogs prolifically. In addition to being knowledgeable in a wide variety of scientific fields, he has that rare ability to clearly articulate the workings of science. A sentiment I've heard him express a few times on the SGU is that contrary to science-deniers' claims of a conspiracy to preserve the status quo, scientists relish when a hypothesis is proven wrong. Or when a provisionally accepted fact is upended. These occurrences create questions. And questions are what fuel science. Like most people, I have little contact with scientists in my daily life. I'd like to think that Dr. Novella's observation is mostly true of scientists in general. He's extremely wary of casually making weak generalizations, but I'd love to hear about the experiences of other people.

This isn't to say that I expect superhuman levels of objectivity and logic of scientists. Everyone has flaws in their thinking. But scientists - at least those who have paid their academic dues - are trained to recognize those flaws so they don't influence the work. What I expect of scientists (and hope of anyone) is healthy skepticism, especially of their own conclusions and biases. This is a basic requirement, really. I try to hold myself to the same standard.

What does this have to do with Serendipaceratops? Paleontology has always been my favorite scientific pursuit to learn about, and part of that is because it's such a rich mental playground, pulling in so many other sciences. Serendipaceratops is one of those tasty mysteries that makes you consider possibilities, flex the brain muscle, so to speak. That it's only one or two bones only makes it more intriguing. Maybe it will never be solved. That's okay. Science is a process, and even dead ends can yield worthwhile insights.

Sometimes when I'm writing I'll imagine someone stumbling across this blog who doesn't care a whit for dinosaurs or paleontology or natural history. They might read about this odd bone from Australia and think that fussing over such a thing is ridiculous. What does it really matter? I can put myself in that person's shoes and understand why digging up ancient bones may seem that way. But I'd ask that person which of the following options is the most ridiculous, when you've pulled a fossil out of the ground.
  1. Make up something off of the top of your head.
  2. Toss it aside and forget it.
  3. Do paleontology.
In my opinion, number three is the only reasonable choice.

Finally, thanks to the commenters yesterday for giving me more to mull over. I've put out a request for a recent paper that offers an alternate hypothesis for Serendipaceratops' identity and may post on that if I'm lucky enough to receive it. If anyone else has any more information that might help, pass it my way - I think I've been pretty diligent about researching this critter, but there's not a lot out there.

Wednesday, June 9, 2010

Serendipaceratops arthurcclarkei, an Australian Mystery

Serendipaceratops arthurcclarkei is one of the mysteries of dinosaur-kind, lurking Gollum-like in the shadows, threatening to overturn everything we know about the ceratopsians, sowing doubt and confusion. Well, maybe not everything, but possibly their origins and certainly their geographical distribution. In March of 2004, National Geographic News posted a story about the Dinosaurs of Darkness traveling exhibition curated by Monash University paleontologist Patricia Vickers-Rich, and the story briefly mentions the strange new dinosaur from Australia:

Other dinosaurs from southern Australia include Serendipaceratops arthurcclarkei, one of the oldest horned, or frilled, dinosaurs known, which suggests that horned dinosaurs may have originated in the southern polar region.

"That group is most well known from Mongolia, where Protoceratops occurs in the very late Mesozoic/late Cretaceous. The material of Australian origin is early Cretaceous," Vickers-Rich said.
Nat Geo's reporter, John Roach, may have misunderstood Vickers-Rich; her quote doesn't claim that horned dinosaurs originated in Australia (and I've been unable to find any quotes from her that do), but refers specifically to those ceratopsians to which Serendipaceratops is most closely related. It's still a puzzling story.


Leptoceratops by Peter Trusler, via Wikimedia Commons.

Known only from a single ulna - and possibly another pulled from the nearby Dinosaur Cove fossil locale - Serendipaceratops is a huge question mark. Initially skeptical, Vickers-Rich and her partner-in-paleontology, Thomas Rich, decided that the ulna belonged to a ceratopsian based on its strong resemblance to the corresponding bone of Leptoceratops, a well-known Late Cretaceous dinosaur from North America. Lepto is closely related to the more famous Protoceratops, also known only from the Late Cretaceous. Therein lies the problem: if you accept the protoceratopsian nature of Serendipaceratops, it lived tens of millions of years before anything that resembled it. What the heck is it doing in Australia?

It may not seem like a big deal, but consider the following:
  • Yinlong, the earliest confirmed ceratopsian, hails from Jurassic China.
  • Every other ceratopsian known to paleontologists comes from Asia, Europe, or North America.
  • The vast majority of protoceratopsians come from China and Mongolia.
At the time of Yinlong, the continents we know today were still mashed together into the supercontinent Pangaea (click for map). Pangaea was a great C-shaped landmass, with the areas we know as Australia and China at opposite ends. It's possible that ceratopsians might have ranged between Australia and China; it simply would have required populations to travel between those terminal points of the "C" via Africa or South America, and possibly India. You would expect to find something similar to either protoceratopsids or primitive ceratopsians somewhere in these places. To date, none have been found (save for one dubious jawbone from South America that has been lost), but there also aren't many rich, temporally relevant dinosaur-bearing deposits in those regions.

In the recent description of Sinoceratops, the only non-North American ceratopsid, Xu Xing wrote that the apparent endemism of ceratopsids to North America probably reflects gaps in the fossil record rather than actual limitations on the family's Cretaceous range. The mystery of Serendipaceratops is complicated by much larger gaps. And at least Sinoceratops has the decency to have been contemporary with its ceratopsid kin.

It seems simpler to me that the ulna's resemblance to that of Leptoceratops is a coincidence. That's where my money would be, if gambling on paleontology was a sane thing to engage in. Hopefully, the notoriously stingy Australian strata will give up more related material. At the very least, if Serendipaceratops is not a ceratopsian, it's a totally unique Australian dinosaur. That's a pretty good resolution, and still a worthy tribute to the man it was named for.

Tuesday, June 8, 2010

Dinosaur! With Walter Cronkite

I'm going to tell you a story about a time when the world was ruled by monster creatures. They were the most spectacular, terrifying, and successful life forms ever, and they ruled the planet for 150 million years... - Walter Cronkite


Back in the early nineties, A&E presented a four-part documentary called Dinosaur! hosted by Walter Cronkite. The first two episodes are available via YouTube user Troodon311, and well worth your time. Here's the first ten minute installment of the first, "A Tale of a Tooth." The four remaining parts, as well as the second episode, are available here. Scrolling through, I'm finding tons of great stuff, including Dino-Riders, Ben Linus, Lloyd Bridges, and Dennis the Menace: Dinosaur Hunter. Best YouTube channel ever.



More chilling than the puppet battle between Megalosaurus and Iguanodon is Bob Bakker's stonewashed vest.

Monday, June 7, 2010

Ceratopsian Wrangling



Here's a roundup of links relating to some of the new ceratopsians we've been delighting in recently. Of course, many of the new taxa introduced in the last couple of weeks come from the long-awaited new book New Perspectives on Horned Dinosaurs: the Royal Tyrrell Museum Ceratopsian Symposium. The symposium was held in the autumn of 2007, and brought together a couple hundred experts in the field to share recent research.

Michael J. Ryan talks Medusaceratops lokii
The Vancouver Sun has an article about Medusaceratops featuring New Perspectives on Horned Dinosaurs lead editor, paleontologist Michael J. Ryan. Regarding the name he gave the new ceratopsian, he tells the paper, "One of the things I have a problem with as a paleontologist is how some of my colleagues come up with terribly unpronounceable names... I like to give my dinosaurs names that roll off the tongue and actually evoke an image." Hear, hear.

Jim Kirkland writes about Diabloceratops eatoni
In a guest post at Dave Hone's Archosaur Musings, paleontologist Jim Kirkland sums up what's cool about the new, also-wonderfully-named Diabloceratops. There are some fine photos of the skull, which is a thing of beauty.

Four foot horns from Mexico

Reconstruction by Lukas Panzarin

Coahuilaceratops magnacuerna is the new ceratopsian from Mexico, making news because of its enormous horns. I'd expect a story about it from Nat Geo soonish, as they partially funded the Utah Museum of Natural History dig.

Ojoceratops fowleri
The Bisti-De-Na-Zin Wilderness of New Mexico recently produced the tyrannosaur Bistahieversor, and now gives us Ojoceratops, a mid-size ceratopsian. Discovered by a team led by Robert M. Sullivan of State College of Pennsylvania, Ojoceratops gets its name from the Ojo Alamo Formation in which its bones were found. It's a controversial rock formation, as it is right at the boundary of the Cretaceous and the Paleocene, the first age of the post-dinosaur world. Paleontologist Jim Fassett has argued for years that dinosaurs may have survived a while after the Chicxulub impact based on fossils found in this layer. Sullivan has argued against this, so I doubt that any such assertions will be in the description. There's a great summary of the Ojo Alamo controversy at Laelaps; articles on Ojoceratops at the Santa Fe New Mexican and Pennlive.com.

These are the few that have received coverage; there are more that haven't had much written about them, including Rubeosaurus, Utahceratops*, and Tatankaceratops. I wrote a bit on Ajkaceratops and a bit more on Sinoceratops. A good place to keep up with recent discoveries, including plenty I haven't had the time to write about, is Dinosaur Central.

Finally, if you're a Facebooker, Ceratopsians have their own fan group, moderated by the Royal Tyrrell's Darren Tanke. More exciting than the Beyonce group, for sure.

*Kind reader 220mya has informed me that Utahceratops is not included in this title, and not yet described.

Friday, June 4, 2010

Vintage Dinosaur Art: John Francis

Triceratops

I think it's only proper to put the spotlight on a ceratopsid this week. These illustrations of the most famous of all,Triceratops, come from a 1981 title in the Rourke Publishing series of dinosaur books. Like the Janet Riehecky series from which last week's Baryonyx title came from, each book focuses on one dinosaur. Rather than presenting a series of facts or conjectures as in the Riehecky books, the Rourke books tell stories. This title is written by Angela Sheehan, but the google machine tells me that there were a number of authors who participated in the series.

The illustrator is John Francis, who has a long record of quality work, and a special interest in natural history.

Angry Triceratops

The story begins with a female trike laying her eggs and leaving them. The nest is plundered by an Ornithomimus - an activity I doubt one would engage in - but Sheehan depicts Triceratops as a disinterested mother. She's exhausted from the egg-laying and chills out in some ferns. At one point, a T. rex rouses her ire and she takes a swing at him. Then, after watching some Stegoceras engage in some ritual head-butting, she dozes off.

Sleeping Triceratops

Francis doesn't go for photorealism or strict anatomical accuracy; the design of his dinosaurs reflect older ideas in paleoart that Gregory S. Paul would effectively put an end to later in the decade. But I like these illustrations for their vibrant, punchy quality, and the way they're embellished with details like the spider spinning its web in the last image. So many children's books on dinosaurs are quickly and sloppily put together, and it's nice to see illustrations done with care. You can check out more of Francis' dinosaurs at his site's gallery.

Thursday, June 3, 2010

Yinlong and the Roots of the Ceratopsian Family Tree

In December, I wrote about one of the coolest toy lines I've seen in a long time: Evolvems, plush animals that reveal one of their evolutionary descendants when turned inside out. The Evolvem I posted was the lone dinosaur pair in the line: Yinlong-Styracosaurus. Styracosaurus is one of the most popular ceratopsids, appearing in children's books and toy lines for years because of its handsome, spike-studded frill. Yinlong, however, is pretty obscure.

It's easy to understand why. It's a recently discovered dinosaur, its Chinese name (meaning "hidden dragon") doesn't immediately suggest "dinosaur" to English-attuned ears, and it's not exactly a giant. To most people, it probably seems pretty humble.


Yinlong downsi by Andrey Atuchin, via the Natural History Museum, London

But the Evolvems brain trust picked Styracosaurus' partner-in-plush for a good reason. Discovered in China in Jurassic rock, Yinlong downsi is the oldest ceratopsian yet discovered. It lived alongside Guanlong wucai, an early relative of T. rex. If you were going to give T. rex and Triceratops the "Muppet Babies" treatment, you could set it in Late Jurassic China.

This spells out a likely Asian origin for the ceratopsians. Sinoceratops, the new Chinese ceratopsid, opens the possibility that these more derived members of the group may also have their origin in China, rather than arising in North America after more primitive ceratopsians found their way there via the Asian-Alaskan land bridge formed in the Cretaceous. It's also plausible, to me at least, that Sinoceratops or its recent ancestors wandered back to Asia from North America. Perhaps something about its biology - more generalized, mixing traits of the centrosaurines and chasmosaurines - made it better suited for its Chinese habitat, thus making this hypothetical migration - probably occurring over many generations - a reasonable pursuit. Bear in mind, I haven't read anyone put this forward, so it's just my idle speculation. Hopefully some earlier Cretaceous strata will cough up some ceratopsids of their own.

Wednesday, June 2, 2010

Dave Dolak

This is amazing. A student at my alma mater, Columbia College Chicago, took this cell phone video of professor Dave Dolak singing to the class.



Columbia is an arts and media school. Dave was the perfect science teacher to wrangle all of those left-brainers right-brainers into tackling science, and the course was one of my favorites. It was called Dinosaurs and More: Geology Explored, and the final project involved synthesizing a topic we had learned about into something artistic. My contribution was "The Dinosaur Genealogy Bop," a rollicking disco throwdown. I'll have to try to find it. It starts with a paleontologist schooling a kid's mom on how stupid the phrase "giant dinosaur dragonfly" is and only gets more unfathomably amazing and intense as it goes on.

Sinoceratops and the Ceratopsian Family Tree

I think I'll keep the ceratopsian train chugging along here. First, a correction. Yesterday I mentioned that the Sinoceratops description in the Chinese Science Bulletin puts forth the idea that the ceratops-ians may have originated in Asia. Actually, Xu Xing and his coauthors write this of the ceratops-ids. Those couple letters make a big difference. My lovely brain has a nasty habit of fudging subtle details like those suffixes. Maybe laying out the context into which these new dinosaurs fit will be a sort of mental strength training.

When I began writing today, I figured I'd talk about Yinlong, an important basal ceratopsian from China. But I think it may be better to draw the big picture, the ceratopsian family tree, if you will, and save Yinlong for tomorrow. This will dip into the often maddening world of taxonomy, the classification of living things, which is an even more difficult undertaking when dealing with a source of data as fragmentary as the fossil record. While I'm not looking to get granular, I'll preface this by saying that names of groups and the members therein may change as paleontologists find new fossils and debate how the old ones relate to each other.

The ceratopsians are a member of the largely herbivorous clan of dinosaurs called the ornithischians, which I discussed a bit in a post from last August. Most of the ceratopsians, save for some of the most primitive, are quadrupedal, and the group ranges widely in size, from as big as a dog to larger than an elephant.


The pelvic differences between saurischians and ornithischians. By yours truly, a derivative work based on separate diagrams by wikimedia user Frederik.

The ceratopsians all share a completely unique bone called the rostrum, which forms the top half of their beaks. Find one of these, and you've got a ceratopsian for sure.

There are many families under the ceratopsian umbrella, but I'm not going to get into the details of all of them. As this review is spurred by the Sinoceratops discovery, I'll instead discuss its family, the ceratopsids: the largest ceratopsians, distinguished from each other by a variety of ornaments on their skull. The basics are the bony frill extending from the back of their heads and the horns, bumps, and knobs on their faces - working from these basic elements, the variety is astounding.

Based on these ornaments, the ceratopsids are then divided into two main posses: the centrosaurinae, which generally bear larger nose horns with smaller frills and brow horns, and the chasmosaurinae, which have the opposite arrangement. Looking at those horns is a good way to get a rough idea of what kind of ceratopsid you're dealing with - just as you might look at the shape of a beak to begin to identify a strange bird in your yard. Some prominent chasmosaurines are Triceratops, Chasmosaurus, and the new Medusaceratops; the centrosaurines include Styracosaurus, Einosaurus, and Centrosaurus. Sinoceratops is notable for the blend of centrosaurine and chasmosaurine characteristics in its skull, which is the basis for Xing's idea of an Asian origin for the ceratopsids.


Centrosaurines, by Nobu Tamura, via Wikimedia Commons

It used to be a given that if a new ceratopsid was discovered, it would be from western North America in Cretaceous rock. Sinoceratops naturally flips the geographical part of that on its head, and raises questions about how wide the range of this classically North American group could have been. Xing floats two guesses as to why ceratopsids are mostly found in North America. First, there may have been factors that limited the ceratopsids geographically, and what we see is what we get. This is certainly plausible, but a bit shaky considering how few windows to the Cretaceous the rocks give us. He favors the second option, which is that we simply haven't found everything. Sinoceratops is a tantalizing look at what may be there waiting to be unearthed.

Tuesday, June 1, 2010

Hellraising Hornheads

You may have noticed a ridiculous number of news stories about ceratopsians - the beaked, frilled, frequently horn-sporting relatives of Triceratops - in the last week or so. Or maybe you don't have a Google Alert set up for "dinosaurs," in which case I should advise you to set one up ASAP. You'll be delighted by how much it raises your esteem with your peers.

Sober social advice aside, the hornheads have been popping up all over the place, due in part to the release of New Perspectives on Horned Dinosaurs from Indiana University Press. The book includes descriptions of a number of new species, including Diabloceratops eatoni, Medusaceratops lokii, and Coahuilaceratops magnacuerna. Coahuilaceratops is making waves for its enormous brow horns and for being Mexico's first ceratopsid, which is the largest, most lavishly ornamented group of horned dinosaurs.

Not to be outdone, China now has one of its own as well; it's named Sinoceratops zhuchengensis and is described in a new paper in the Chinese Science Bulletin. Both of these national firsts extend the group's known western North American range. Smaller, primitive ceratopsians like Psittacosaurus and Protoceratops are well-known from Asia, so the Sinoceratops discovery is especially significant. The authors of the study present their own revision of the ceratopsid family tree and state that the ceratopsians may have originally arisen in Asia, flourishing generations later in North America. The recently introduced Ajkaceratops - which was a member of the broader ceratopsian family - would seem to support this idea, as its ancestors were likely also of Asian descent.

If you want to impress people by picking a favorite dinosaur that's a little left-field, cool-looking and cool-sounding, you've got some solid options here. Personally, I'm going with Medusaceratops - check out the amazing Luis Rey reconstruction here.

Also cool is that the cover model for New Perspectives on Horned Dinosaurs is none other than LITC's patron dinosaur, Chasmosaurus. Cleveland Museum of Natural History paleontologist Michael Ryan, lead editor of the book, identifies the artist as the Royal Tyrell Museum's Donna Sloan.