Fossils

A fossil is any trace of past life that lived prior to historic times. A scientist who studies fossils is called a paleontologist. Fossils come in many forms - seashells, animal bones, leaf impressions, wood, even animal burrows or footprints preserved in rock. They also come in many sizes, ranging from less than 1/100th of a millimeter to greater than tens of meters. Because soft flesh does not preserve well, many fossils represent only the hard parts of the original animal, such as the shells of molluscs or the bones of land animals like the mastodon. Some fossils, such as wood, bones, and teeth, are petrified, or turned to stone. Petrification occurs when minerals replace the organic material that originally comprised the organism. Other fossils such as seashells are preserved with little change. Fossils provide important information about the past life on earth. Based on the types of plants and animals present in a rock unit, scientists can often determine what ancient climates were like as well. Fossils are also useful in correlating and determining the age of rock units.

Florida is a fossil-hunter's paradise. Fossils present in the exposed rocks in our state range from 45 million-year-old "sand dollars" to bones and teeth from the "Ice Age" sabertooth tiger, which lived in Florida just 10,000 years ago. Much of Florida's bedrock, which is largely limestone, is comprised of the shells of animals that lived in the shallow seas once covering our state. Fossil seashells abound in the banks of both panhandle and southern Florida rivers.

Bones from Ice Age mammoths and mastodons accumulate on stream beds. Shark teeth wash up on the beaches of southwestern Florida. Moreover, open-pit mineral mines and quarries statewide yield abundant fossil bones, teeth and shells from both land and marine animals. For publications on specific groups of fossils, see the FGS List of Publications. The following publications provide general information about Florida's fossils.