December 14, 2012
There’s always something new to learn about dinosaurs. Whether it’s the description of a previously-unknown species or a twist in what we thought we knew about their lives, our understanding of the evolution, biology, and extinction is shifting on a near-daily basis. Even now, paleontologists are pushing new dinosaurs to publication and debating the natural history of these wonderful animals, but the end of the year is as good a time as any to take a brief look back at what we learned in 2012.
For one thing, there was an exceptional amount of dino-hype this year. A retracted paper that mused on the nature of hypothetical space dinosaurs, a credulous report on an amateur scientist who said he had evidence that all dinosaurs were aquatic, and overblown nonsense about dinosaurs farting themselves into extinction all hit the headlines. (And the less said about the Ancient Aliens dinosaur episode, the better.) Dinosaurs are amazing enough without such sensationalist dreck, or, for that matter, being transformed into abominable human-raptor hybrids by Hollywood.
Not all the dinosaurs to wander into the media spotlight were atrocious, though. The glossy book Dinosaur Art collected some of the best prehistoric illustrations ever created, and the recently-released All Yesterdays presented dinosaurs in unfamiliar scenes as a way to push artists to break from severely-constrained traditions. Dinosaurs were probably much more unusual than we have ever imagined.
Indeed, new discoveries this year extended the range of fluff and feathers among dinosaurs and raised the question of whether “enfluffledness” was an ancient, common dinosaur trait. Paleontologists confirmed that the ostrich-like Ornithomimus–long suspected to have plumage–sported different arrangements of feathers as it aged. New insight on the 30-foot-long carnivore Yutyrannus affirmed that even big tyrannosaurs were covered in dinofuzz. And while both Ornithomimus and Yutyrannus belonged to the feathery subset of the dinosaur family tree that includes birds, the discovery of fluff on a much more distantly related theropod–Sciurumimus–hints that feathers were a much older, more widespread dinosaur feature than previously expected. Paired with previous finds, Sciurumimus suggests that protofeathers either evolved multiple times in dinosaurian history, or that the simple structures are a common inheritance at the base of the dinosaur family tree that was later lost in some groups and modified in others.
While some traditionalists might prefer scaly dinosaurs over fuzzy ones, feathers and their antecedents are important clues that can help paleontologists explore other aspects of paleobiology. This year, for example, researchers reconstructed dark, iridescent plumage on Microraptor on the basis of fossil feathers, and, as display structures, feathery decorations will undoubtedly have a role to play in the ongoing debate about how sexual selection influenced dinosaur forms. Feathers can also be frustrating–a new look at the plumage of Anchiornis and Archaeopteryx will undoubtedly alter our expectations of how aerially capable these bird-like dinosaurs were and how they might have escaped predatory dinosaurs that dined on the prehistoric fowl. Such lines of inquiry are where the past and present meet–after all, birds are modern dinosaurs.
Feathers aren’t the only dinosaur body coverings we know about. Skin impressions, such as those found with the ankylosaur Tarchia, have also helped paleontologists discern what dinosaurs actually looked like. Pebbly patterns in Saurolophus skin can even be used to differentiate species, although paleontologists are still puzzled as to why hadrosaurs seem to be found with fossil skin traces more often than other varieties of dinosaur.
And, speaking of ornamentation, a damaged Pachycephalosaurus skull dome might provide evidence that these dinosaurs really did butt heads. How the adornments of such dinosaurs changed as they aged, though, is still a point of controversy. One of this year’s papers threw support to the idea that Torosaurus really is a distinct dinosaur, rather than a mature Triceratops, but that debate is far from over.
Other studies provided new insights into how some dinosaurs slept, the evolutionary pattern of dinosaur succession, what dinosaur diversity was like at the end of the Cretaceous, and how dinosaurs grew up, but, of course, how dinosaurs fed is a favorite place that lies at the intersection of science and imagination. A poster at the annual Society of Vertebrate Paleontology meeting deconstructed how Tyrannosaurus rex–suggested to have the most powerful bite of any terrestrial animal ever–tore the heads off of deceased Triceratops. The herbivorous Diplodocus, by contrast, munched soft plants and stripped branches of vegetation rather than gnawing on tree bark, and the tiny, omnivorous Fruitadens probably mixed insects with its Jurassic salads. Studying dinosaur leftovers also explained why paleontologists didn’t find more of the mysterious Deinocheirus, which thus far has been identified by only one incomplete fossil–the long-armed ornithomimosaur was eaten by a Tarbosaurus.
We also met a slew of new dinosaurs this year, including the many-horned Xenoceratops, the archaic coelurosaur Bicentenaria, the sail-backed Ichthyovenator, the stubby-armed Eoabelisaurus, and the early tyrannosaur Juratyrant. This is just a short list of species I wrote about–a few that add to the ever-increasing list.
To properly study dinosaurs and learn their secrets, though, we must protect them. One of the most important dinosaur stories this year wasn’t about science, but about theft. An illicit Tarbosaurus skeleton – pieced together from multiple specimens smuggled out of Mongolia–has brought wide attention to the fossil black market, as well as the poachers and commercial dealers who fuel it. The fate of this dinosaur remains to be resolved, but I’m hopeful that the dinosaur will be returned home and will set a precedent for more vigorously going after fossil thieves and their accomplices.
Out of all the 2012 dinosaur stories, though, I’m especially excited about Nyasasaurus. The creature’s skeleton is as yet too fragmentary to know whether it was true dinosaur or the closest relative to the Dinosauria as a whole, but, at approximately 243 million years old, this creature extends the range of dinosaurs back in time at least 10 million years. That’s another vast swath of time for paleontologists to examine as they search for where dinosaurs came from, and those discoveries will help us better understand the opening chapters in the dinosaurian saga. That’s the wonderful thing about paleontology–new discoveries open new questions, and those mysteries keep us going back into the rock record.
And with that, I must say goodbye to Dinosaur Tracking. On Tuesday I’m starting my new gig at National Geographic’s Phenomena. I’ve had a blast during my time here at Smithsonian, and I bid all my editors a fond farewell as I and my favorite dinosaurs head off to our new home.
Editor’s Note: Best wishes to Brian on his future travels and we all thank him for his hard work over the past 4 (!) years, writing every day about something new on dinosaurs. It’s not nearly as easy as he makes it look. – BW
October 24, 2012
Heterodontosaurs were freaky. If you don’t believe me, check out the time-lapse reconstruction of this Heterodontosaurus head by artist Tyler Keillor. Released earlier this month in conjunction with a massive monograph on these dinosaurs in ZooKeys, the video beautifully demonstrates how our changing understanding of paleobiology is reviving even classic dinosaurs.
Heterodontosaurus was originally described in 1962. This ornithischian was a relatively small dinosaur, only about four feet long, but the creature’s name is a clue to its Jurassic weirdness. Heterodontosaurus, like its close relatives, had a toolkit of different teeth (or a “heterodont dentition) in its mouth that would have allowed the dinosaur to slice meat, insects, and vegetation. The dinosaur’s teeth are a tell-tale indicator that it was an omnivore. Even more recently, a heterodontosaurid from China named Tianyulong showed that these ornithischians –as distantly-related to birds as possible while still being a dinosaur–had manes of feather-like bristles. Put the whole thing together, and you get what Keillor has created–a Mesozoic equivalent of a wild boar, and one of the strangest-looking dinosaurs ever.
[Hat-tip to Thomas Holtz.]
October 18, 2012
About 95 million years ago, in Cretaceous Australia, an aggregation of small dinosaurs scurried along an ancient lake margin in what is the world’s only known “dinosaur stampede.” Exactly what caused the dinosaurs to scatter is a mystery. A set of larger tracks, found at the same quarry, have been cast as the footprints of a big predator who was stalking the mixed herd. But, as the rock record shows, this bigger dinosaur passed by at a different time than that of the stampede. And that bigger dinosaur may not have been a carnivore. A recent reassessment of the site raised the possibility that a large herbivore, akin to Muttaburrasaurus, left the tracks. We really don’t know what caused so many little dinosaurs to skitter away, or even come together in such numbers.
Nevertheless, the dramatic imagery of something like Australovenator pouncing on little ornithopods is hard to beat, and the Lark Quarry site–where the stampede is preserved–recently spawned a hyperbolic documentary. Now there’s a musical version, too. At the 2012 Museum’s Australia National Conference in Elder Hall, Adelaide, performers Michael Mills, Amy Donahue, Tahlia Fantone, Morgan Martin and Tom Goldsmith played out their own version of the dinosaur stampede.
Sadly, the performance perpetuates the myth that the stampede was sparked by a prowling carnivore. The truth is that we don’t know. I can’t necessarily blame the creators, though. Singing “You have to run, run, run. You have to hit top speed. Why? We don’t really know. But there’s still evidence of a dinosaur stampede!” doesn’t work quite as well.
October 16, 2012
For over a century, non-avian dinosaurs have been symbols of extinction. Our awe at their success, and our puzzlement at their ultimate demise, have made them perfect foils for our worries and fears. During World War I, for example, anti-war protestors cast dinosaurs as brutes who drove themselves into extinction by investing too much in their armor and weapons. Later, during the Cold War era, the asteroid strike that closed the Age of Dinosaurs was presented as a Mesozoic precursor to what mutual assured destruction might do to the planet. Not only have we looked to dinosaurs for lessons about what the future might hold, but we’ve also used them as icons of what might happen if we trade compassion for size and strength.
The 1967 Russian cartoon Mountain of Dinosaurs used extinction in a more specific and culturally subversive way. Rather than a literal lesson about dinosaurs–the fossil record doesn’t contain any hint that courting sauropods gave each other edible bouquets of ferns–the short warns about what happens if powerful stewards meant to care for individuals actually stifle those they are charged to protect. Dinosaurs didn’t die because of climate change, the short says, but because their eggs became so thick-shelled in response to colder temperatures that the baby dinosaurs couldn’t hatch. The shells (yes, the eggshells speak) mindlessly drone that they are doing their “duty,” but by growing thicker and thicker they kill the nascent sauropods. The scene is the saddest dinosaur cartoon I’ve ever seen, and it seems to be a metaphor for the Soviet government suppressing the rights of individual citizens. Indeed, the death of dinosaurs was not only used by Americans to issue dire warnings–they are an international symbol of extinction.
October 12, 2012
About five years ago, the movie gossip site Ain’t It Cool News pulled back the curtain on a Jurassic Park we’ll never see. A scrapped script for the franchise’s fourth film told a tale of dinosaurs that had not only been brought back from extinction but had also been further modified to make them humanoid soldiers. Sadly, the plot had nothing to do with Axe Cop’s Dinosaur Soldier.
Thanks to a little Internet sleuthing, we now know what those dinosaurian troops would have looked like. Earlier this week io9 posted concept art from the discarded version of Jurassic Park 4. It turns out that, for once, Hollywood hype was right. If this movie was actually made, Jurassic Park 4 would have been one of the strangest blockbuster-budget features ever made. I guess Spielberg really wasn’t kidding when he hinted that the story would have taken the franchise in a totally new direction.
Even though I’ll watch just about anything with dinosaurs in it–hell, it’s part of my job–I think this version of Jurassic Park 4 is best left to the annals of movie history. The dinosaurs have thrice imperiled people on islands and have torn a path of devastation over the mainland once. The fact that Jurassic Park 3 brought some of the original characters back to one of the islands showed the the franchise ran out of ideas very early, and inventing dinosaur soldiers was a crazy attempt to add novelty to an already faltering series. Not to mention the fact that creating dinosauroids to wipe out already-created raptors and tyrannosaurs sounds like the cure might end up being worse than the initial problem.
Which brings up the question of whether there should even be another Jurassic Park sequel. The franchise left off on a bad note, not to mention the atrocious comics and lackluster video games that have lately cropped up. Maybe it’s best to simply let the dinosaurs rest.
Michael Crichton’s original story was brilliant, and the movie adaptation will always be a cultural milestone for being the first film to convincingly bring dinosaurs back to life. But it seems that Universal hasn’t had a clue what to do with the dinosaurs since they got them. Finding ever-more conceits for people to run for their lives from Mesozoic monsters is difficult, and maybe there simply isn’t a way to recreate the awe audiences felt when they saw the first film. You would think the studio would have learned their lesson after running the JAWS franchise into the ground, but, given that Hollywood is so low on ideas that Hungry, Hungry Hippos is really going to be a movie, I guess I can’t blame them for going back to Jurassic Park‘s primeval wellspring one more time.