File:The continent we live on (1961) (20496865468).jpg

Title: The continent we live on
Identifier: continentweliveo00sandrich (find matches)
Year: 1961 (1960s)
Authors: Sanderson, Ivan Terence, 1911-1973
Subjects: Physical geography; Natural history
Publisher: New York : Random House
Contributing Library: New College of California
Digitizing Sponsor: Internet Archive

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in.iierial was washed downslream aiul ilepositfJ In-re but, allcrnalins with iheso. were \onf, pcriixis when fine sill and nuid accunuilated This was in ihe middle of whai we now call the age of reptiles, or the Jurassic Period, and the sandstones then formed make up what we now call the Morrison beds. Durinjj floods, the corpses of the animals that inhabited both this delta and the surrounding lands were from time to Imie carried along by the waters, and were deposited on sand bars, just as the bodies of domestic animals are today by the Green River. Then, as the flesh was eaten by scavengers, the bones sank into the sand and were entombed. Fortunately for us. many of those so buried in this place were fossilized. Several great changes later took place, the whole area having, among other things, been covered by a large sea or part of the ocean for a long period. But eventually Ihe land rose again, and erosion went to work on the now upended and exposed sections of the deposits formed in the ancient delta. Again very fortu- nately, a scientist happened to spot some of these fossilized bones during a field trip in the year 189.? and recorded the fact. Fifteen years later one Dr. Earl Douglass made an extended search whidT finally brought him to the place of which we speak. Any citizen may now stand here and gaze upon the skeletons of dinosaurs, both monstrous and minute, still embedded in the sandstones of the ancient delta where they once lived and died. Here the past stares you in the eye with a kind of knowing twinkle, as if to say. "So you didn't really believe what you saw in the museum, did you?"': and this can be most disturbing. You begin to think of elephants and rhinoceroses and other unlikely- looking creatures; and then, perhaps shrugging, you turn to contemplation of the mighty dinosaur commonly called Bronlo- saunis. and you realize that it is only a bit less likely. Then other strange thoughts come to mind. These creatures, being reptiles, almost certainly laid eggs: and. as far as we know from the few of these found, these were comparatively very small. Did baby dinosaurs, whidi need not have been much bigger than baby alligators when they first popped out of their eggs, frisk about in the bright sun. or did they dig themselves into the sand, or dart for water before one of their larger cousins could snap them up? There is so much more we would like to know about these fabulous creatures. What for instance did they eat? What color were they? Did some of them have flaming red heads, iridescent green bodies, and bright blue tails, such as one lizard has today? Or were they all just great drab-colored beasts like elephants and rhinos? The very idea of baby dinosaurs is in some respects rather startling, especially when you contemplate the remains of their vast parents. But there were also little dinosaurs—quite apart from baby big ones—that were not much bigger than chickens. One (Laosaunisl that was first found here had an over-all length of only two and a half feet, including its long, reptilian tail, and it apparently rushed about on its hind legs just as the Basilisk Lizard of Central America does today. But there are other even more intimate things to be seen here. Prominent among these are considerable quantities of pebbles, mostly about the size of your clenched fist, that are polished as if by a jeweler. No known natural process can so polish a pebble, for even the finest powdered dust leaves tiny scratches that render the surface dull, while chemicals only etch it. These stones were a mystery until a clutch of them were found occu- pying the position once held by the stomach of a small fossil reptile known as Proliguanadoii. From this discovery it became apparent that many dinosaurs, like birds today, might have had
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Bristle-cove pines. It has been di^ some spec- imens of these gnarled, scrawny!' < in Califor- nia's White Mountains are about four thousand years old. and thus among the oldest living trees. to swallow pebbles to aid in the grinding of coarse food in their stomachs. And that would be the one place where such pebbles could be so brightly polished. This seems to bring these impos- sible-looking reptiles much closer, for it gives us one more point to understand about them. The ultimate in getting to know the dinosaurs was probably achieved by Roy Chapman Andrews in bringing to light a dinosaur nest containing its eggs, some of which had within them little dinosaurs about ready to hatch. The remains of some three hundred individual dinosaurs of a dozen different species have now been extricated from the sandstones of this place. Among these are more than two dozen skeletons so complete that they have been mounted as a whole in museums. In addition to dinosaurs, two kinds of crocodilians. one a real pigmy, and a very ordinary-looking tortoise have come from the same strata. Among the dinosaurs are the vast brontosaur now known as Apatosaurus. its more slender relative Diplodocus with its horsy head and strange, slender teeth: and the long-necked Btirosaurus. two kinds of Cainariisaunis. and so many remains of the fabulous Stegosaurus (which probably lived on the drier uplands) that Ihe diggers became frankly bored with them Of bipedal plant-eaters there are three: and there are two flesh-eaters, one called Antrodemus. with a body about the size of a mule and two-inch teeth with serrated cutting edges.

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