The Florida Platform block began to form by a combination of volcanic activity and deposition of marine sediments along the northwest portion of Africa about 530 million years ago (early Ordovician Period). During the formation of the supercontinent, Pangaea, the Florida block was sandwiched between what were to become North and South America and Africa (late Carboniferous, 300 million years ago). Near the Triassic/Jurassic boundary (210 million years ago) Pangaea began to divide into two major continents, Laurasia (North America, Europe and portions of Asia) and Gondwana (South America, Africa, India, Australia and Antarctica). Later, as the Atlantic Ocean seafloor continued to spread, North America split from Laurasia and drifted away in a northwesterly direction, dragging the Florida Platform block with it.

The marine environments of Florida during the early Cenozoic were part of the Tethys Sea, a circum-global seaway that allowed for the broad dispersal of many groups of organisms into new areas and unfilled niches. During this time under the sea, the skeletons of billions upon billions of marine invertebrates deposited onto the seafloor formed the limestone platform on which Florida now sits.

Eroded terrestrial sediments from the north covered the Florida Platform forming islands and eventually allowing for diverse habitats from dense forests to open grasslands. Diverse fossil beds stand as awesome testimony to the vast array of terrestrial life forms that migrated to Florida since its first documented emergence in the middle Oligocene (35 million years ago).

Numerous advances and retreats of the sea have occurred since Florida's emergence. Some areas experienced great erosion by the advancing surf. New layers of sediments and invertebrates were often left behind by the retreating sea. Erosion of sediments and limestone by freshwater runoff created karst landscapes, known for sinkholes and caves. These would later become deadly traps for unsuspecting animals, resulting in some of the most prolific fossil sites in the world.

A mass migration of plants and animals between North and South America occurred in the Pliocene (2.3 million years ago). The Great American Interchange resulted from the formation of a land bridge connection between the two continents. The sudden appearance in the Florida fossil record of animal groups previously known only from South America testifies to this open exchange of terrestrial life forms.

Towards the end of the Pleistocene Epoch, 100,000 years ago, the last Ice Age got underway, and Florida's land area grew, until, at its greatest extent, it was three times its current size. At the end of the Ice Age, paleoindians arrived in Florida. With them came the rapid extinction of the large terrestrial animals (megafauna), a fascinating story also recorded in Florida sediments.