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Sculptures of Tyrannosaurus (foreground) and Parasaurolophus (background) at the George S. Eccles Dinosaur Park.

There are at least two ways to look at dinosaurs. You can examine their fossilized bones, the stuff that comes directly from the fossil record, or you can imagine what those bones would have looked like when they were clothed in muscle, sinew, and skin during the animal’s life. At the George S. Eccles Dinosaur Park in Ogden, Utah, these two visions are brought together.

By the time I visited the park last month I had already seen my fair share of Utah’s dinosaurs, but the Ogden attraction was unique in that it boasted a large collection of dinosaur sculptures. Some of the life-sized dinosaurs were relatively old (they dragged their tails and looked rather dim-witted), while other newer models better fit our present understanding of dinosaurs as active, dynamic animals. The “vintage” dinosaur models were mixed in with the newer ones, creating an odd scene that hinted at the evolution of our understanding about what dinosaurs were like.

While the park is most famous for its sculptures, it also has a museum. The facility boasts a number of fiberglass skeletons and donated fossils, yet they are not presented in an organized fashion. A chunk of meteorite is placed at the feet of a mammoth skeleton while a model of a woolly rhinoceros stands right below the museum’s Tyrannosaurus rex, for example. There are a few labels for some of the larger pieces, but fossil bric-a-brac is scattered everywhere; the place is in desperate need of a good curator. Visitors can also peek in on prep work being done at a fossil lab in the museum, although it is unclear whether any scientific research is carried out there.

After visiting places like the Museum of Ancient Life, Ogden’s dinosaur park paled in comparison. I have no doubt that kids will love it though. It is a great place to just go look at fossils and dinosaurs, and if you (like me) prefer your dinosaurs presented with a little more science there are plenty of other museums in northern Utah to check out.

The famous "Dueling Dinosaurs": A Velociraptor and Protoceratops that became stuck together in death. From the Anatomical Record paper.

In one of the early scenes of Jurassic Park, the fictional paleontologist Alan Grant terrorizes a child visiting his dig site with a Deinonychus claw. If the dinosaurs were still alive they would have used the enlarged claw on their second toes to rip open the boy and eat his guts, Grant says, a fate Grant himself almost meets when he encounters the cloned predators later in the film. But did Deinonychus and its relatives like Velociraptor really use their claws to tear open their prey?

As part of the U.K. documentary miniseries The Truth About Killer Dinosaurs, a team of paleontologists created a reconstruction of a Velociraptor leg. When they tested it to see if the dinosaur’s claw could have been used to disembowel prey, they found something they did not expect. The huge foot claw of the “raptor” dinosaurs was not very good for slashing. Instead, it seemed to be better adapted as a grappling device, like a hook that could be used to hold onto or pin down prey. The claw may have even had a “locking” mechanism that would have kept the claw latched into the victims of Velociraptor, thus allowing the predator to dispatch its prey with its hands or jaws.

Some of those same researchers have now followed up with a new study published in a special all-dinosaur edition of the Anatomical Record, this time looking at a hand claw from Velociraptor. What they discovered was that the hand claw of the predatory dinosaur was also well-adapted to anchoring into surfaces. It was even strong enough to have held the dinosaur up if it attempted to climb a tree. Velociraptor lived in an arid landscape and so it probably did not actually engage in this behavior, but it is something Hollywood directors might want to take into account when they start filming Jurassic Park IV.

There is still much more work to do (the scientists have yet to test their hypotheses with other dinosaurs related to Velociraptor or even model how the entire hand might have worked while latching onto prey or a surface), but the studies have important implications for the evolution of birds. Velociraptor and Deinonychus are among the dinosaurs most closely related to birds, and they evolved from much smaller ancestors. It may be that the “killer claws” of these dinosaurs allowed the early, small members of this group to climb trees. Once up in the canopy, some of these dinosaurs, like the ancestors of Microraptor, might have evolved the ability to fly. The fact that such claws also allowed these dinosaurs to better hold onto and anchor themselves into prey was just a matter of putting a pre-existing trait to a new use and may have led to the evolution of the larger predatory forms like Utahraptor.

Birds did not directly evolve from Velociraptor, Deinonychus, or Microraptor, but the way these dinosaurs used their claws might provide a crucial clue to how their close avian relatives evolved. Paleontologists have debated for years whether birds evolved flight from the “trees down” or the “ground up,” and these new studies throw some tentative support to the “trees down” camp. Hopefully further studies will soon be undertaken to flesh out this hypothesis.

A collection of seized fossils being returned to Chinese officials.

Much to the frustration of paleontologists, fossils are big business. Sites all over the world are raided for the petrified treasures, which are then shipped to private collectors. Such practices destroy dig sites, rob countries of their natural history, stifle our scientific understanding of the past, and deprive the public a chance of ever seeing the fossils. Black market fossil dealers do make mistakes, though, and in a ceremony last week U.S. Immigration and Customs Enforcement (ICE) and U.S. Customs and Border Protection officials returned a collection of significant fossils to China.

Among the fossils seized was the skull of a saber-toothed cat, the skull of the small horned dinosaur Psittacosaurus, and 24 dinosaur eggs. The eggs had been found by customs agents at Washington’s Dulles International Airport, while the other fossils were discovered while being processed at Chicago O’Hare International Mail Facility. Scientific experts from the Virginia Museum of Natural History and the Field Museum in Chicago, respectively, examined the fossils and determined them to have come from China. The fossils may have been purchased from dealers in different countries, but there was no doubting that the specimens had come from China.

What will happen to the fossils now? The Chinese government is sending scientists to come and retrieve the fossils. The bones and eggs will brought to the Geological Museum of China for research.

A Corythosaurus in Beijing. From reader Paul Trap.

Most of the Dinosaur Sightings that come in are of Tyrannosaurus, so it was refreshing when a snapshot of a hadrosaur came our way. Reader Paul Trap sent us this snapshot of his son posing next to what would appear to be a Corythosaurus outside the Beijing Museum of Natural History. The crest on the dinosaur’s head is not quite right, though; it looks like a bit of a punk hadrosaur to me!

Have you spotted a dinosaur out in public? Take a picture and send it to us at dinosaursightings@gmail.com and you might see it here!

A restoration of the skeleton of Raptorex. From the Science paper.

Tyrannosaurus and its close kin Daspletosaurus, Tarbosaurus, Albertosaurus, and Gorgosaurus were among the largest land-dwelling predators the world has ever known. They had massive heads full of huge, serrated teeth and were the dominant predators in the times and places in which they lived. Surprisingly, though, many of the features that make these dinosaurs so recognizable appeared much, much earlier. In this week’s edition of Science, an international team of scientists describes a new, diminutive precursor to the more familiar Cretaceous giants. It was discovered in approximately 130-million-year-old rocks in China. They have named it Raptorex kriegsteini.

At first glance you could be excused for thinking that Raptorex was the juvenile stage of one of the later tyrannosaurids. At only about 10 feet long, it had long, gracile legs, a slender-looking head, a large eye socket, and ridiculously small forelimbs which terminated in claws. While it was not quite a fully mature individual, it was not the juvenile stage of an already-known dinosaur. It was something scientists had never seen before, one that can tell us much about how its giant cousins evolved.

Up until now paleontologists have been working with the bookends to the tyrannosaur evolutionary series. There were the classic, large-bodied terrors like Tyrannosaurus and the more recently-discovered, raptor-like dinosaurs like Dilong and Guanlong from China. Raptorex fits somewhere in between, and even though it was small it possessed many of the characteristics seen in its larger relatives.

While Raptorex did not have the heavy, knobbly head of Tyrannosaurus, its head was relatively large for its body size; about 10 percent larger for its body size than the skulls of earlier relatives like Guanlong. Raptorex also had incisor-like teeth in the front of its mouth, a condition seen dinosaurs like Tyrannosaurus but not the early tyrannosauroids. Add to that the expanded areas for jaw muscle attachment and you get a “miniature” tryannosaur with a terrifying bite.

What is really interesting, though, is that Raptorex had small arms in which the humerus (upper arm bone) is longer than the lower arm. These short, robust arms were tipped in claws. While a biomechanical study of the arms of Raptorex has yet to be carried out, this arrangement suggests that short-yet-strong arms of the tyrannosaurids evolved when the lineage was still relatively small.

This discovery is very important because just why Tyrannosaurus and its close relatives had such small arms has long been an evolutionary puzzle. The arms of the relatively small Raptorex may help paleontologists understand whether arm size was an adaptation to a particular hunting style or the consequence of something else, like a change in growth rate. In addition to the other characteristics documented by the paper’s authors, many of the tell-tale tyrannosaurid traits first evolved when the lineage was still small, contrary to what paleontologists had expected.

The description of Raptorex is made all the sweeter by the fact that it was almost lost to science. In an University of Chicago interview, Paul Sereno, the lead author on the new paper, explains that the skeleton of Raptorex was excavated by a local person and sold to a private owner. This private owner then approached Sereno, and the scientist was adamant that the skeleton be donated to science (and eventually returned to China). Had Raptorex stayed in private hands we would still be in the dark about this crucial point in tyrannosaur evolution.