Vertebrate animals are animals that have backbones. Their skeletons are inside their bodies, covered by skin and other tissues. These skeletons are made of either cartilage or bone. Vertebrates have a nerve cord (spinal cord) that runs along the back of the animal, close to the skin.
Living examples today include fishes, amphibians, reptiles, birds and mammals. Some vertebrate fossils come from remains of the animals. This is the same as with fossils from invertebrates (animals without backbones). Others are merely traces of the animals, such as footprints and burrows.
In Ohio, geologists have found fossils of vertebrate animals from Devonian, Mississippian, Pennsylvanian and Permian rocks, and in deposits from the Pleistocene Ice Age.
- Rhodes, Frank H.T. Fossils: A Guide to Prehistoric Life; Golden Press, New York; 1962.
- Skinner, Brian J. & Stephen C. Porter The Blue Planet: An Introduction to Earth System Science; Wiley, New York; 1995.