The Ellicott Shale is exposed in Chautauqua Gorge of northwestern Chautauqua County, New York. It is a gray shale that averages about 150-feet thick. The Gowanda Shale outcrops on the shore of Lake Erie Phylum Brachiopoda Brachiopods are simple two-shelled organisms similar to modern mussels. Brachiopods are one of only seven phyla that have a geologic record that spans the entire Phanerozoic eon, which began 540 million years ago. There are brachiopod fossils in rocks dating back to the earliest part of the Cambrian period.
Brachiopods are solitary animals.
They did not form colonies, although many clustered together. They secreted a shell that was made up of two halves that enclosed most of the animal. Each shell, or valve, had bilateral symmetry. Brachiopods were incapable of actively pursuing food. Their sessile, or motionless, way of life put great limits on their feeding ability.