One of the problems with taxonomic classifications of extinct organisms is determining what the normal range of variation was. For example, in the article referenced here, researchers have used comparative analysis of a saber-toothed cat's jaws and teeth to help determine the animal's taxonomy.
But how can we be reasonably confident that the differences in the teeth and jaws really translated into true intraspecies differences?
As a side note, Florida is one of the most fossiliferous states in the US, and much of it is related to the phosphate deposits that cover much of the central region of the state. The most fossiliferous formation is actually called the Bone Valley Formation, and is intimately related to the phosphate deposits. (1)
So what was going on here? Certainly there are no fossil-rich layers forming anywhere in Florida right now. There's some connection between the phosphate, the Bone Valley formation, and the 10-20 feet of sand that overlies the whole stratigraphic package.
I'm starting to wonder if there is a relationship between the Lake Agassiz paleoflood that had massive effects in the Caribbean, and the unique geological features of Florida (2).
Via Catherine Russell