The GRI Collections
Welcome to the GRI Collections, a representative sample of fossils studied at the Geoscience Research Institute.
What are fossils?
When the conditions are right, organisms’ remains or impressions can be preserved in rock. Rapid burial is often a factor. Much of what we know about the ecology of the ancient world can be ascertained by the study of fossils.
The Cambrian Explosion
Scientists have long been puzzled by the diverse phyla present in the Cambrian layer. If the geologic column can be read as a timeline, how did most marine phyla practically appear all at once?
The Coconino Sandstone
Prior to the 1930s, scientists widely accepted the theory that the footprints found in the Coconino Sandstone were made underwater. This theory was abandoned in favor of a dry desert interpretation that fit better with a gradualist paradigm. But was this change guided by evidence, or ideology?
Radiation of Fish
Several major groups of fishes appear in Devonian and Upper Silurian rocks without a series of ancestral species. The disparity between these species and those found in lower strata is a major challenge to the model of gradualism.