Unusual fossil sites

There are other strange places to search for fossils but hardly common enough to deserve more than a passing mention. In dinosaur country from Colorado and Utah into Canada, occasional piles of gastroliths, or gizzard stones, are found. Some ancient lizards swallowed pebbles to help grind their food, and by definition these stones are fossils. On occasion the gas-troliths were themselves fossil pebbles. Nicely rounded and tumbled, these fossils are all of animals older than the Cretaceous or Jurassic.

Ancient man accumulated objects just as the modern fossil collector does. A strange fossil would be picked up and perhaps even buried with the owner. Crinoid stem segments with natural holes in the center were ideally suited to be made into necklaces to adorn the necks of prehistoric men and women. In ancient living sites and graves, fossils collected thousands of years ago can occasionally be collected again.

Fossils are even found in other fossils. The trilobite Vogdesia crawled into abandoned shells of large straight cephalopods that littered the bottom of Ordovician seas. Both shell and trilobite sometimes wound up as fossils. Collectors in northeastern Iowa have found that by breaking open large cephalopod shells they may discover an occasional trilobite. Fossil nema-todes were found embedded in fossil scorpion skin from Devonian rocks of the northern Rockies. Petrified wood from some areas, when broken apart, reveals the clams known as teredos, still preserved at the end of their burrows. Delicately preserved flowers and leaves from the late Pleistocene are known to science mainly through their unique preservation in the mouths and stomachs of Siberian mastodons and mammoths that were frozen with their mouths still full of food. The diet of Ordovician cephalo-pods that lived in Arkansas seas has been studied through their stomach contents, now pyritized like the cephalopods themselves. Scales, fins, and teeth of small Pennsylvanian fish are known only from the fossilized excrement of other fish and sharks, never having been found as complete fossils in the rocks.

A remarkable find was made in the petrified stump of a Pennsylvanian tree when it was broken apart. The tree had evidently been hollow, and this hollow was the home of a rare early reptile. The tree and the reptile were fossilized together, the stump protecting the fragile bones from separating and disintegrating. One more proof of what every collector eventually discovers — fossils are where you find them!

0 0

Post a comment