SALTASAURUS: Choosing What is Best

Drawing by Lady of Hats

The last of Dinosaurs with big noses (Macronaria) were the Titanosaurs, who lived from the late Jurassic to the end of the Cretaceous Period (about 65 million years ago). Like their name, Titanosaurs were huge. In addition to their size, these Dinosaurs had thick forearms, barrel-shaped bodies, and broad chests.

            Like many Titanosaurs, Saltasaurus had body amour, resembling that of modern crocodiles. In the late 1800s, paleontologists found fossils of circular and oval-shaped bony plates. These armored plates (called osteoderms) were about four inches (11 cm) in diameter. Since these plates were not the same as those from armored Dinosaurs such as Ankylosaurus, scientists were confused as to whether they belonged to a Dinosaur (and if they did, which one). Saltasaurus’ discovery in Argentina, in 1980 by Jose Bonaparte and Jaime Powell, solved this puzzle. When the scientists assembled her fossil bones, they realized that these round disks belonged on her back. These large bony plates of Saltasaurus went from her neck to her tail.

            The last of the Sauropods to evolve, Saltasaurus was still going strong at the end of the Mesozoic Era. Because few Sauropod fossils were found in the Northern Hemisphere, paleontologists believed that this Suborder of Dinosaurs had died out years earlier. However, They were abundant in South America. Separated from the other continents, South America hosted many Titanosaurs (who are Sauropods). For example, Saltasaurus was named for Salta City in Argentina, where she was found. In fact, Titanosaurs were the dominant plant eaters there and in Africa.

In Patagonia, paleontologists found the nesting grounds of Saltasaurus. Neatly spaced, each nest was carefully tended by the Mothers. Moreover, Saltasaurus Mothers would return to the same place at the same time to nest. Most scientists regard these signs that she was a good mother.

            Besides her scales, Saltasaurus had other unique features. Where her fingers should be, She had stumps. Moreover, her pencil-shaped teeth reminded scientists of Diplodocus (another Sauropod). (These two Dinosaurs had evolved their type of teeth separately.) Since She could not chew her food, Saltasaurus swallowed the leaves whole. Her huge stomach chamber did the digesting, fermenting the plant matter, and expelling the gases.    

            Though different from many other Titanosaurs, Saltasaurus chose what was best for Her. Her peg-like teeth could strip shrubs of their tough leaves. Her barrel-shaped body fermented her food. Her bony plates broke the teeth of an attacking predator. Though her choices may seem strange to others, She knows what works for Her. When you are faced with choices, remember what Saltasaurus teaches.

BRACHIOSAURUS: Ask Questions

One of the best known Dinosaurs is Brachiosaurus, who was featured in the move, “Jurassic Park,” (Spielberg, 1993). This giraffe-like Dinosaur blew snot out of his nasal opening in the middle of his forehead, onto the people below. Small wonder since Brachiosaurus belonged to the Family of Dinosaurs called Macronaria, who are noted for their long necks and big noses.

            However, the movie got the function of this opening wrong. The big hole on the forehead of Brachiosaurus was probably not used for blowing snot out. The nasal opening at the end of his snout was for that. The hole in his forehead had other uses: what they were are hotly debated by modern paleontologists. The earliest naturalists believed that it acted as a snorkel since they thought that Brachiosaurus lived underwater. When that theory was proven false, then the scientists said that the forehead cavity was for breathing and blowing out snot. When that hypothesis was questioned, some paleontologists then reasoned that the tissue in the opening was a thermostat to regulate heat. Others think that perhaps it was used as a sound sac. More than likely, his forehead opening probably had multiple uses.

            Discovered in Colorado in 1900, Brachiosaurus (which means “arm reptile”) was named by Elmer Riggs, a noted paleontologist, three years later. In examining the fossil bones, he noted that they resembled a modern giraffe’s skeleton. In fact, this Dinosaur is known for having the longest front legs of any animal. (They were higher than his rear legs.) With his steeply sloping back and long neck, Brachiosaurus did resemble a giraffe. Since He was the first of his type of Dinosaur to be discovered, other similar fossils were usually classified with Him, which led to some confusion. For example, Giraffatitan, found in Tanzania, by Werner Janensch in 1906, has been the object of intense debate. Are Giraffatitan and Brachiosaurus, the same or different species? Adding to this debate is that much of what people know about Brachiosaurus comes from studying Giraffatitan.

            In reconstructing his life, paleontologists think that Brachiosaurus did live like a giraffe. With his immense height and long neck, He could graze the tops of trees. To pump blood so high up to his head, Brachiosaurus probably had the same circulatory system as Giraffe. Unlike Giraffe though, Brachiosaurus had a sharp claw on the inner toe on each of his feet. With it, he could uproot plants for eating.

            Seeing beyond the obvious is what Brachiosaurus teaches. The big hole on his forehead first encouraged people to imagine Him snorkeling under the water. Later they believed He blew snot out of it. Today, scientists are not really sure what all of its uses are. Brachiosaurus encourages people not to assume the obvious, but to investigate and ask questions. Remember that just because He is tall, does not mean that Brachiosaurus plays basketball.

DIPLODOCUS: Endearment

by Arthur Weasley (Wikipedia)

Through the efforts of the famed industrialist Andrew Carnegie (U.S.), Diplodocus became world famous. Carnegie had generously sent out a large number of skeletal casts of Diplodocus to museums around the world. After She was discovered in 1877 in the United States, naturalists, at that time, thought that Diplodocus was the largest of the Dinosaurs. (Argentinosaurus, at twice the size of Diplodocus, is now regarded to be the largest.) Because of her near-complete skeleton in the Carnegie Museum of Natural History, She was named Diplodocus carnegii in 1901.

            When Diplodocus was first examined by Othniel C. Marsh (noted paleontologist), he saw that She had extra bones underneath her spine. Therefore Marsh called Her “Diplodocus” (double beam) for the chevron-shaped bones which supported her neck and tail. These special bones are common in the skeletons of other Sauropods.

            Because of her extra-long neck and tail, Diplodocus was one of the longest of the Dinosaurs. Her tail, which was about half of her length, counterbalanced her considerable elongated neck. (Seismosaurus, a larger Dinosaur, is actually an abnormally long species of  Diplodocus.)

            When scientists first studied Diplodocus, they thought that She lived in the water. Her nostrils, which they believed were located on the top of her head, acted as a snorkel. For many years, illustrations showed Diplodocus standing in a swamp or lake. However, in the 1950’s and 60’s, two paleontologists proved otherwise. Dr. K.A. Kermack (U.K.) demonstrated that the water pressure would have killed Her if She did snorkel underwater. Then a few years later, Dr. Robert Bakker (U.S.) established that Diplodocus lived on land instead of water.

            Later the paleontologists reasoned that Diplodocus used her long neck to reach high up into the trees to eat leaves. Though her neck did contain fifteen vertebrae, She did not have the flexibility needed to lift her neck high.  When Diplodocus wanted to eat, She would grip a branch with her teeth and strip the leaves off. Also, sometimes She would poke her head into the forest fringes or push a tree over with her massive body to eat the leaves.

            Because of her early world-wide fame, Diplodocus became endeared by people. The museum workers who cleaned Diplodocus’ skeleton often called Her “Dippy.” Roaming about the countryside during the Jurassic, this long Dinosaur, with small spines running down her back, often pushed trees over using her elephant-like feet. That such a massive animal could endear Herself to people is a remarkable feat. We should ponder how She did that. Could it be that She was simply Herself, and people loved Her for it?