The Study of Change Over Time:
Researching evolutionary relationships between organisms that lived tens to hundreds of millions of years ago can be difficult. The most pressing problem associated with the study of evolution in an ancient organism is the lack of fossilized creatures to study, because in many environments fossil preservation is a rather uncommon occurrence. Fossilized remains of organisms are best preserved under water, when an animal's "hard parts" (mostly shell or bone) can fill with sediment or be replaced by mineral precipitation. This makes the study of terrestrial organisms especially difficult. Because only organisms that dwell under water and contain "hard parts," are preferentially preserved, the fossil record is especially rich in marine organisms with shells or skeletons. If geologists are lucky enough to find a fossil species preserved in abundance in sediments, then examination of evolutionary change within the species can begin.
Within this module we present detailed information on two such locations, one along the western shores of Chesapeake Bay, MD, the other in north of Utica, N.Y., at Trenton Falls, NY.
Last modified October 06 2008 02:07 PM