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An early restoration of Hadrosaurus mounted in 1868. From Wikipedia.

November 24, 2009 will mark the 150th anniversary of the publication of Charles Darwin’s On the Origin of Species, and scientists have already started the celebrations. Last week, for example, the University of Chicago hosted a series of talks by some of the top evolutionary scientists working today. Among those delivering lectures was paleontologist Paul Sereno.

According to notes posted by blogger PZ Myers, early on in the discussion Sereno puzzled over why Darwin neglected many fossils, and dinosaurs in particular, in his most famous book. Dinosaurs are very closely related to evolutionary science today, but Darwin appeared to ignore them. Why?

Sereno posited that Darwin’s tense relationship with the Victorian anatomist Richard Owen, who coined the term “dinosaur” in 1842, kept him from talking about dinosaurs. Owen was a brilliant scientist but his cantankerous attitude was well-known. Worse than that, even though Owen was an evolutionist he disagreed strongly with Darwin over what the mechanism of evolution was, and his criticism of Darwin has fooled many people into thinking that Owen was a young-earth creationist.

The problem is that there is virtually no evidence to show that Darwin ignored dinosaurs because he was afraid of big, bad Richard Owen. In all of Darwin’s correspondence with other scientists there is almost no mention of dinosaurs at all, and when Darwin later addressed dinosaurs he did so to show how little was known about the fossil record.

As I wrote earlier this year, during Darwin’s time dinosaurs were enigmatic creatures. Not only were they very different from living reptiles, they were very different from each other, and most of the first specimens that were discovered were extremely fragmentary. It was not until 1858, the year before On the Origin of Species was published, that the relatively complete skeleton of Hadrosaurus was found in New Jersey.  This discovery, along with several others, made scientists start to reconsider what dinosaurs looked like right as Darwin’s book was being published.

I think Darwin was wise to leave dinosaurs out of On the Origin of Species. At the time of his writing, only a few genera were known from incomplete specimens, and no one would be able to tell what they had evolved from or if they left any living descendants. The seemingly aberrant forms of the dinosaurs hinted that there was more yet to be found in the fossil record, but they could not yet be pressed into the service of holding up the evolutionary mechanism Darwin was proposing.

Yet this, too, is a hypothesis. Darwin is long dead, and we cannot ask him why dinosaurs did not figure into his work. Still, I think the view presented here more closely represents Darwin’s concerns that what Sereno has proposed.

A restoration of the nearly-complete skull of Alioramus altai. From the PNAS paper.

It has been a good month for tyrannosaur research. We have been introduced to the comparatively tiny tyrannosauroid Raptorex, have learned that Tyrannosaurus probably suffered from a parasitic infestation similar to one seen in living birds, and now a team of paleontologists led by Stephen Brusatte has announced a new member of the “tyrant” family tree, Alioramus altai.

“But wait,” I hear you say. “I have been on a Walt Disney World ride that has an Alioramus in it. It’s not really new.” While it is true that the genus Alioramus, which lived about 70 million years ago in what is now Mongolia, was first described in 1976 by Russian paleontologist Sergei Kurzanov, it was only known from an incomplete skull. The new specimen described by Brusatte and colleagues in the journal PNAS is much more complete and represents a new species of the same genus, which they have named Alioramus altai. It provides a much better look at what this relative of larger tyrannosaurs like Tarbosaurus was like.

What is most immediately recognizable about Alioramus altai is its skull. Its close tyrannosaurid relatives all had heavy, deep skulls that allowed them to exert crushing bite forces that could ram their teeth through bone. Alioramus altai, on the other hand, had a shallower skull and long-snouted appearance. I have no doubt it skull could deliver a deadly bite, but not the damage the jaws of something like Tyrannosaurus could inflict.

In fact, this long-snouted appearance is similar to what paleontologists expect juvenile Tyrannosaurus and Tarbosaurus to have looked like. Could Alioramus altai have just been a juvenile Tarbosaurus (another tyrannosaurid from Mongolia that lived about the same time)? The paleontologists looked at the growth pattern in the bones of the dinosaur to find the answer.

While the specimen of Alioramus altai the team described was not yet a full-grown adult, it was distinctly different from some juvenile Tarbosaurus specimens that have been found. In addition to its more slender jaws, it had at least eight small horns covering its face, including a row on the top of its nose and two below the eyes. (The fact that this specimen was a juvenile suggests that adults of this species would have even more impressive knobs and protuberances on the skull.) Other tyrannosaurids have a few similar ornaments on their skulls, but Alioramus altai was far more decorated. It also appears that Alioramus altai would have been somewhat smaller than some of its giant relatives, although an adult specimen will have to be found to determine just how big it got.

Alioramus altai also has some important implications for our understanding of tyrannosaur evolution. It was one of the last tyrannosaurus, living close in time to when Tyrannosaurus lived in prehistoric North America, but it was a very different kind of predator. This means that it was not an evolutionary stage leading up to a dinosaur like Tyrannosaurus but represented a distinct kind of tyrannosaur that probably fed on smaller prey. Its discovery has increased the diversity of the known types of tyrant dinosaurs, and its discovery suggests that other unique tyrannosaurus may yet be found.

For more on this discovery, see a guest post by lead author of the new study, Stephen Brusatte, at the Archosaur Musings blog.

Falcarius, on display at the Utah Museum of Natural History.

On the last day of our vacation, my wife and I had a few hours to kill before we had to get to the airport, so we started poring over a map of Salt Lake City to see if there was anything fun to do. A little icon in the upper right corner of the map caught our attention: there was a natural history museum not far from the airport, the Utah Museum of Natural History.

As we pulled up to the museum, which was tucked away in the University of Utah campus, I was not quite sure what to expect. Was it going to be a musty, dust-filled exhibit hall like the museum back at Rutgers? Were there any dinosaurs inside?

I was pleasantly surprised. Not only was the museum large and well-kept, but there were plenty of dinosaurs to see. Most of them were collected in the paleontology hall on the second floor. The centerpiece of the exhibit featured Late Jurassic dinosaur celebrities like Allosaurus, Ceratosaurus, and Stegosaurus, but what really impressed me were the new discoveries on display.

It can be difficult for a museum to keep up with paleontology. New discoveries and revisions of old ideas occur so frequently that even exhibits constructed 10 years ago have parts that are out-of-date. Given the Herculean effort it takes to put up mounted skeletons and create displays, it is no wonder that many museums let things slide until an overhaul of its dinosaur exhibits becomes unavoidable, but the Utah Museum of Natural History is different.

In addition to plaques outlining recent research conducted by UTNM scientists, the Cretaceous section of the dinosaur hall contains some unusual displays. One features a dinosaur called Falcarius, a herbivorous relative of the “raptor” dinosaurs that was described in 2005 and may have been covered in a kind of feathery fuzz! To its right lies the skull of an as-yet-undescribed horned dinosaur informally known as the “Last Chance ceratopsian.” This dinosaur had a big Jimmy Durante nose, two horns over its eyebrows, and a long frill topped with two curved horns. This skull, and others like it, might tell us a lot about the evolution of horned dinosaurs in North America, and I look forward to seeing it described in print!

There are even more dinosaurs downstairs. In addition to a rock wall flecked with casts of dinosaur bones, visitors can check out the paleontology prep lab. Here visitors can watch volunteers and professional scientists clean and piece together dinosaur fossils they have collected. Here science-in-action is what is on exhibit. No one was there that day, but I could plainly see the skulls of several horned dinosaurs lying in plaster cradles on the lab benches.

The dinosaurs will have to move to new digs in the not-too-distant future, though. Construction recently started on a new Utah Museum of Natural History which is set to open in 2011.

If you want to enjoy Ice Age 3: Dawn of the Dinosaurs, you are going to have to suspend your belief for a bit. There is no use nitpicking over a children’s movie featuring talking extinct species of mammals from different places and time periods (to say nothing of saber-toothed squirrels). The latest installment of the franchise is different, however, in that it introduces the unlikely herd of mammalian heroes to an underground world populated by dinosaurs.

It all starts to go wrong when Sid the ground sloth stumbles across some enormous eggs. Feeling left out by the fact that the mammoths Manny and Ellie are expecting a baby and are about to start a new family, Sid appoints himself the mother of the eggs. (Diego, the saber-toothed cat, is having his own worries about losing his predatory edge.) These soon hatch into baby dinosaurs, but the well-intentioned Sid has no idea how to properly care for them. Needless to say the real mother of the babies is none too happy when they go missing, and being that she is a rather large Tyrannosaurus, that is bad news for the mammals. In gathering up her young ones she picks up Sid, too, and his friends set off to rescue him.

The mammals quickly find that they are out of their depth, but they get some help from a crazed survivalist weasel named Buck. Buck has only one eye due to a past encounter with a large, whitish menace he calls “Rudy.” From that point on the film settles into its search-and-rescue theme, even as Sid somehow becomes accepted by the Tyrannosaurus mother. The visuals are spectacular and the direction is great, but the dinosaurs are sometimes annoyingly over-stylized. While most of the creatures in the film are embellished in one way or another, the dinosaur designs are a bit over the top (such as small, Monolophosaurus-like predators that have quills that shiver when the dinosaurs roar).

There are even some dinosaurs that never existed. When “Rudy” finally appeared on the screen, for example, my wife leaned over and asked, “what kind of dinosaur is that?” “It’s a nothing-o-saurus,” I replied, as the monster was more of a bipedal crocodile than a dinosaur. “Rudy” is a scary villain, especially in 3D, but with so many giant predatory dinosaurs now known I would have liked to have seen an attempt at one like Giganotosaurus.

If you liked the previous two Ice Age films then you will probably like the third one. It is a “safe” movie that is not especially exciting but still is funny enough to be enjoyable (unlike this summer’s other dino film). And if you are offended at dinosaur running around with Pleistocene mammals, just remember it could be worse: humans could be riding them.

Alamosaurus. From Wikimedia Commons.

Fossil trackways have shown paleontologists that some sauropod dinosaurs moved together in herds. But how were their herds organized? Were they made up only of particular age groups or were individuals of different ages all mixed together? In a new paper in Palaeogeography, Palaeoclimatology, Palaeoecology, scientists Timothy Myers and Anthony Fiorillo discuss two different sites that suggest that at least some sauropods segregated their herds by age.

Before discussing the fossil sites in detail, Myers and Fiorillo review some of the problems in inferring behavior from fossil trackways alone. A photo included in the paper, for instance, shows the tracks of a human next to those of a grizzly bear. Was this person walking alongside gentle Ben? No, the tracks had been made hours apart. The same principle holds for fossil tracks. The presence of tracks made by two individuals in the same place does not necessarily mean they were there at the same time. Further evidence would be required to show this was true.

There can be difficulties with evidence from bone beds, too. The fossils from Mother’s Day Quarry in Montana are from a herd of sauropod dinosaurs that may have died during a drought. What is strange, however, is that nearly all the bones are from juvenile and sub-adult animals. Immature animals typically suffer higher death rates than adults during droughts, but the question was whether this site represents a herd of immature animals or simply the immature portion of a larger herd. The lack of adults and the fact that the bones had not been transported after the animals died led Myers and Fiorillo to suggest that the Mother’s Day Quarry site represents an actual herd of immature animals separate from adults.

The Big Bend site in Texas differs in that it consists of three juvenile Alamosaurus that died and were buried together. Like the Montana site, this bone bed represents a single event rather than the accumulation of multiple skeletons over time. The fact that no adult bones are found and that no accumulations of multiple Alamosaurus adults are known suggests that these dinosaurs herded together when young but became more solitary as they became mature.

So what do these two sites mean? Factors that might potentially bias the formation of bone beds must be kept in mind, but they appear to suggest that, in at least some sauropods, juvenile individuals formed groups separate from herds of mature individuals. This may have to do with size. The adults were much, much larger than immature individuals and may have had different dietary needs. This may have segregated herds by age with the younger animals grouping together for protection. This type of age segregation was probably not present in all sauropods, but it may have been prevalent among some of the largest species.

The staff here at Smithsonian seems to have developed a strange fascination with dead things. There’s the Dinosaur Tracking blog, of course, which is concerned with a superorder that went extinct 65 million years ago. And at our new sister blog, Surprising Science, some of the first posts are about woolly mammoths (a mere 10,000 years dead) and the bones of astronomer Nicolaus “the earth is not the center of the universe” Copernicus (d. 1543).

Surprising Science is written by Sarah Zielinski, a biology-major-turned-journalist and an assistant editor at Smithsonian. She is interested in most types of science (”whatever is in front of me,” she says) but will focus on the subjects we tend to cover in the magazine: geology, archaeology, astronomy, animals (living or dead) and stories that have art or history or travel tie-ins. But above all, stories that are weird or quirky or unexpected or amusing. We hope you’ll enjoy it.

It’s the most wonderful time of the year! No, not that holiday with all the jingle bells and mistletoe business. It’s almost Halloween, the holiday that’s all about candy, petty vandalism and dress-up. Ever want to tyrannize the world like a T. rex? Lumber around gulping party snacks like an Apatosaurus? Stain the carpet like a coprolite? This is the holiday for you, and we want to hear all about it.

We’re looking for the Best Costume Ever, Dinosaur Division. Please email us at smithsonianmagazine@si.edu to submit your photos from this year or years past.

For inspiration, here are some last-minute costume ideas for your kids or even your pets.

And even though crocodilians and dinosaurs diverged hundreds of millions of years ago, you’ve got to see this.

Walter Alvarez, the guy who figured out that dinosaurs were doomed by a massive asteroid that slammed into the Earth, just won a big prize.

The prize is Earth Science’s answer to the Nobel, the Vetlesen Prize.

The asteroid impact set off “a giant tsunami, continent-scale wildfires, darkness, and cold, followed by sweltering greenhouse heat. When conditions returned to normal, half the genera of plants and animals on Earth had perished,” Alvarez writes on his Website.

The impact also left two major clues: a layer of iridium, which is an element found in comets and asteroids but is rare on Earth, and a 110-mile-wide crater near what is now the Yucatan Peninsula. Alvarez dated both to 65 million years ago, a.k.a. End Times for the dinosaurs.

Several scientific fields that are snubbed by the Nobels have established their own “me too!” prizes. Math has the Fields Medal, for instance, and high tech has the Millennium Prize. (It’s administered by Finland, which might reflect a certain amount of rivalry with those other Scandinavian countries that are so prize-happy.) And purists know that the Nobel for Economics isn’t really a Nobel—it’s administered by Sweden’s central bank in honor of Alfred Nobel. But I know I’m forgetting some. Anybody? Help me out here—what other fields have their own versions of the Nobel?