Florida is known as one of the richest areas for paleontological finds, with fossilized specimens dating back 50 million years to the Eocene Epoch. At that time, the region was entirely covered by ocean and the remains of plants and animals became entombed in layers of sediment. With very little geological activity such as volcanic eruptions or earthquakes to disrupt the landscape, remains often went undisturbed for tens of millions of years.
Among the marine species found in Florida as fossils are seals, walruses, alligators, whales, and sharks (as long as 60 feet). One of the most common finds of vertebrate fossils is shark teeth, both from extinct and living species, which include mako, snaggletooth, and megalodon. Even after land emerged, large rivers coursed through Florida and these buried numerous terrestrial species.
Florida’s fossil record is of critical interest to paleontologists, as it helps complete their knowledge of Cenozoic terrestrial life across eastern North America. In most regions only invertebrate specimens such as crinoids, mollusks, and coral survive in the fossil record. In addition, such fossils may be encased in hard rock and challenging to dig out. By contrast, Florida’s land vertebrate fossils, spanning the Oligocene, Miocene and Pliocene periods, are relatively easy to find and secure. Lying close to the surface and often in good condition, they are constantly being uncovered by the movements of water in river gravel or beach sand.
One of the most fossil-rich regions of the state is Bone Valley, a phosphate mining district of central Florida. Unlike most fossils throughout the southeast, these specimens lack the staining of brown or black muck associated with those retrieved in streams and rivers. Inhabiting dry earth, they exhibit remarkable color and detail.
Interestingly, a large number of species that came to Bone Valley did so because Florida remained frost-free at a time that advancing glaciers made other regions uninhabitable. These included animals that traveled from Asia to North America across the Bering Strait, when the sea was lower and the land bridge existed. Other species migrated along the Gulf of Mexico’s rim, following a route now under water.
Nearly all the largest animals on earth went extinct in the Pleistocene (Ice Age) between eight and 12 thousand years ago. Collectively known as megafauna, those found in Florida include giraffe-like animals, beavers (the size of bear), saber-tooth cats, and mammoths. Other animals represented in the state’s fossil record include ancient horses, camels, bison, and giant armadillo and sloth. For those interested in exploring finds from the region, the Mulberry Phosphate Museum features the bones of massive prehistoric whales, as well as giant shark teeth. The reason why no dinosaurs are found among this assemblage is that they went extinct 65 million years ago, at a time when what is now Florida was still completely submerged in ocean.
Fossil hunters statewide must acquire a Florida Fossil Collecting Permit. A key requirement of the low-cost permit is that any fossil finds (excluding shark teeth) be cataloged and reported annually. Popular regions for surface collecting include coastal areas such as Manasota Key Beach and Venice Beach. For larger specimens such as megalodon and mammoth teeth, diving or snorkeling gear is a necessity. The Peace River, best visited during the dry season, also offers interesting terrestrial and aquatic finds. A few years ago, a pair of young amateur paleontologists made a remarkable discovery of a partial mammoth skeleton on the river’s southern section, with shoulder bones, ribs, teeth, and partial legs excavated. These specimens are on display in Gainesville at the Florida Museum of Natural History.
