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Central Texas is a land of Cretaceous limestone. Road cuts expose layers stacked upon layers; a closer inspection reveals the remnants of past seas - echinoderms, bivalves, gastropods. A creek may cut through the stone, releasing long-entrapped shells, the curls of “Devil’s toenails,” ear-shaped oysters, fan-like pelycepods. Sharks teeth, dark against the lighter stone, retain their serrations. If you are observant, perhaps you will notice a small fragment of bone, perhaps from some marine reptile, washed out of the embankment.
And then there are the dinosaurs. In Central Texas, the ground once shook under herds of the massive Paluxysaurus Jonesi, the State Dinosaur of Texas. The armored Pawpawsaurus trudged along, blinking through its armored eyelids. Tenontosaurus, a horse-sized vegetarian, and other larger Iguanodonts, browsed the low vegetation, perhaps stripping the fronds off of ferns, as Hypsilophodonts ran through the underbrush, fleeing Deinonychus, the “terrible claw.” And at the top of the food chain stood the carnosaur Acrocanthosaurus, its back arched, its head down, stalking through the conifers and cycads, bursting out of the foliage and across the mud flats to chase down a straggling Paluxysaurus.
And then there are the dinosaurs. In Central Texas, the ground once shook under herds of the massive Paluxysaurus Jonesi, the State Dinosaur of Texas. The armored Pawpawsaurus trudged along, blinking through its armored eyelids. Tenontosaurus, a horse-sized vegetarian, and other larger Iguanodonts, browsed the low vegetation, perhaps stripping the fronds off of ferns, as Hypsilophodonts ran through the underbrush, fleeing Deinonychus, the “terrible claw.” And at the top of the food chain stood the carnosaur Acrocanthosaurus, its back arched, its head down, stalking through the conifers and cycads, bursting out of the foliage and across the mud flats to chase down a straggling Paluxysaurus.
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This past weekend I was part of a trip through the Cretaceous, beginning with a visit to Dinosaur Valley State Park in Glen Rose. Despite the rain earlier in the week, the river was running low enough to reveal numerous tracks, and perhaps the faster flow even aided visibility, flushing out sediment from the prints. At least two sections of Paluxysaurus tracks were visible, as well as several tracks of Iguanodonts and the Actocanthosaurus. It is somewhat surreal, walking literally in the footprints of dinosaurs. The interpretive center at the Park headquarters still labels Paluxysaurus as Pleurocoelus, but the casts of the skeletal feet of dinosaurs placed over the casts of the footprints are particularly helpful to understand the shape of the prints, as well as see how they determined which prints belonged to which dinosaur.
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The next stop was still in Texas, and still Cretaceous, but the fossils were imports from Wyoming. The SWAU Paleontology lab is in the process of cleaning and preparing a wonderful Triceratops skill, one of the many specimens they have from their dig in the Upper Cretaceous soils of Wyoming. Still partially encased in plaster, the horns strengthened by two-by-fours, the last foot or so of the snout still being worked on at the workbench.
Around the room, the shelves are lined with Hadrosaur limbs, a few fused sacrum, and numerous ribs. In the next room, we see molds used to cast important fossils. A few boxes of Legos provide the material to frame the molds. In the next room, a Pachycephalosaurus skull graces the counter, like the bald dome of a monk. There are drawers full of vertebrae, others host toes. A drawer of teeth showcases the wide variety of sizes and shapes found. A Hadrosaur jaw, when turned, reveals rows of teeth, a conveyor belt of slicing, grinding dentures. A scapula shows the damage from a tumor, a reminder that even dinosaurs had to deal with disease. A hollow leg bone highlights the lightness and likely speed of a theropod, likely a Tyrannosaurus, but also perhaps the fragility.
Perhaps the most exciting here are the Nanotyrannus bits and pieces. There remains much debate as to whether Nanotyrannus is its own species, or a juvenile Tyrannosaur, but either way, it is exciting as, piece by piece, the toe bones are laid beside the claw. Claws and teeth are of course some of the most notable pieces of the carnivorous dinosaurs, but seeing the whole toe laid out just seems to provide a better sense of size and functionality. But the pinnacle of this visit are half an upper and half a lower jaw of the Nanotyrannus. From different sides of the skull, they still let one visualize the size of the mouth, the larger teeth of the upper jaw curving serrated knives, still sharp long after their last bite.
It is one thing to see the dinosaurs rebuilt, mounted in the museum. It provides a sense of scale, a thing of awe and wonder. But in the lab, it is the details that matter. The small becomes magnified, the difficulty of the puzzle placed before the paleontologist is magnified, as fragments, chips, cracks and nicks needing stabilized, filled, await replacement to finalize the fossilized bone. The tools are an awl, dental picks, a brush - fine work even on the largest specimens. It is a balance between a ton of rock and fossilized bone, and the tiniest of picks and brushes.
Around the room, the shelves are lined with Hadrosaur limbs, a few fused sacrum, and numerous ribs. In the next room, we see molds used to cast important fossils. A few boxes of Legos provide the material to frame the molds. In the next room, a Pachycephalosaurus skull graces the counter, like the bald dome of a monk. There are drawers full of vertebrae, others host toes. A drawer of teeth showcases the wide variety of sizes and shapes found. A Hadrosaur jaw, when turned, reveals rows of teeth, a conveyor belt of slicing, grinding dentures. A scapula shows the damage from a tumor, a reminder that even dinosaurs had to deal with disease. A hollow leg bone highlights the lightness and likely speed of a theropod, likely a Tyrannosaurus, but also perhaps the fragility.
Perhaps the most exciting here are the Nanotyrannus bits and pieces. There remains much debate as to whether Nanotyrannus is its own species, or a juvenile Tyrannosaur, but either way, it is exciting as, piece by piece, the toe bones are laid beside the claw. Claws and teeth are of course some of the most notable pieces of the carnivorous dinosaurs, but seeing the whole toe laid out just seems to provide a better sense of size and functionality. But the pinnacle of this visit are half an upper and half a lower jaw of the Nanotyrannus. From different sides of the skull, they still let one visualize the size of the mouth, the larger teeth of the upper jaw curving serrated knives, still sharp long after their last bite.
It is one thing to see the dinosaurs rebuilt, mounted in the museum. It provides a sense of scale, a thing of awe and wonder. But in the lab, it is the details that matter. The small becomes magnified, the difficulty of the puzzle placed before the paleontologist is magnified, as fragments, chips, cracks and nicks needing stabilized, filled, await replacement to finalize the fossilized bone. The tools are an awl, dental picks, a brush - fine work even on the largest specimens. It is a balance between a ton of rock and fossilized bone, and the tiniest of picks and brushes.
![Picture](/uploads/1/0/5/5/10551590/3971033.jpg?295)
The final stop on the trip was to a Museum, the Fort Worth Museum of Science and History. Here, the mounted Paluxysaurus dominates the room, looking for a way back onto the plains of Texas. Behind, the Tenontosaurus tosses a casual glance over his shoulder at his much larger roommate. Striking in this Tenontosaurus mount are the fossilized tendons, providing additional strength to the tail. Another interesting fossil is the skull of a Pawpawsaurus, a nodosaur (an ankylosaur without a clubbed tail). The museum also has a display of different types of Dinosaur teeth, some exhibits on how fossils are unearthed and moved, comparisons of dinosaur and other animal bones, and a fossil cycad.
With the exception of I-35 traffic, it was a great trip. The footprints gave a sense of motion, of life, to the normally static dinosaurs. Only a living creature leaves footprints behind, and seeing different animals all walking on the same layer of now rock is a reminder that the dinosaurs didn’t just live alone, but existed in ecosystems, little different than the extant animals. The Forth Worth museum then gave a sense of overall scale to the Paluxysaurus, the Central Texas sauropod that left its tracks in Glen Rose. But it was the paleo lab that really tied everything together, that connected the dinosaurs to those who uncover them, who rebuild them, who try and make sense of their biology, their lifestyle, their environment. Rarely are dinosaurs ever found as complete, articulated skeletons. Rather they are usually a few bones, a few fragments, something far different than the mounted skeletons at the museum.
With the exception of I-35 traffic, it was a great trip. The footprints gave a sense of motion, of life, to the normally static dinosaurs. Only a living creature leaves footprints behind, and seeing different animals all walking on the same layer of now rock is a reminder that the dinosaurs didn’t just live alone, but existed in ecosystems, little different than the extant animals. The Forth Worth museum then gave a sense of overall scale to the Paluxysaurus, the Central Texas sauropod that left its tracks in Glen Rose. But it was the paleo lab that really tied everything together, that connected the dinosaurs to those who uncover them, who rebuild them, who try and make sense of their biology, their lifestyle, their environment. Rarely are dinosaurs ever found as complete, articulated skeletons. Rather they are usually a few bones, a few fragments, something far different than the mounted skeletons at the museum.