 Complete the following phrase:  The Paleolithic epoch, the oldest and longest period in the history of mankind, is divided by specialists into three stages of development: Lower Paleolithic, Middle Paleolithic and Upper Paleolithic. The chronological frame of the Paleolithic coincides with that of the Pleistocene the first period of the Quaternary, and is marked by four great glaciations, as established in the Alps Günz, Mindel, 