The Quaternary Period is the geologic time period from the end of the Pliocene Epoch roughly 1.806 million years ago to the present. The Quaternary includes 2 geologic subdivisions -- the Pleistocene and the Holocene Epochs. In a recent revision of the international classification of geological time periods, the Quaternary was subsumed into the Neogene. The move has met with some resistance from geologists.