Definition: Compose a new way to ask the same question. The new question must be asking the exact same thing as the original question does. Without any other information, you should be able to tell that the original question and the new question are the same. Preserve bracketed phrases in your new question. You can change the rest of the question provided the above requirements are satisfied. The new question must have a natural, fluent formulation, as if it were composed by a native English speaker. You will be given three pieces of information to help you create better questions. Those are: "Answer": the answer to the question, e.g., "Honolulu". "Answer Type": the type of the answer, e.g., "Location". "Auxiliary Information" is a detailed description of some concepts mentioned in the question, if any.
Input: original question: Which organism classification has the latest fossil record of [Pleistocene]?
answer: mesotheriidae
answer type: Organism Classification.
auxiliary information: The Pleistocene /Ààpla…™st…µsiÀên/ is the geological epoch which lasted from about 2,588,000 to 11,700 years ago, spanning the world's recent period of repeated glaciations. Charles Lyell introduced this term in 1839 to describe strata in Sicily that had at least 70% of their molluscan fauna still living today. This distinguished it from the older Pliocene Epoch, which Lyell had originally thought to be the youngest fossil rock layer. He constructed the name "Pleistocene" from the Greek œÄŒªŒµ·øñœÉœÑŒøœÇ, pleƒ´stos, "most", and Œ∫Œ±ŒπŒΩœåœÇ, kain√≥s, "new"; this contrasting with the immediately preceding Pleiocene, and the immediately subsequent Holocene epoch, which extends to the present time. The Pleistocene is the first epoch of the Quaternary Period or sixth epoch of the Cenozoic Era. The end of the Pleistocene corresponds with the end of the last glacial period. It also corresponds with the end of the Paleolithic age used in archaeology. In the ICS timescale, the Pleistocene is divided into four stages or ages, the Gelasian, Calabrian, Ionian and Tarantian. All of these stages were defined in southern Europe.

[Pleistocene]is the latest fossil record of what organism classification?