The last major one of these "glacial" time periods came during the Pleistocene Epoch
[DOC] [TLE] Quaternary | geochronology | Britannica.com [PAR] Oct 12, 2015 ... Quaternary, in the geologic history of Earth, a unit of time within the Cenozoic Era
, ... During and between these glacial periods, rapid changes in climate and sea 
... of the Pleistocene Epoch to the beginning of the Quaternary Period, and ... 
came to favour dividing the Cenozoic Era into two other periods, the... [DOC] [TLE] Pleistocene - History of Earth's climate [PAR] Mesozoic was the time of the dinosaurs, and Cenozoic is the era of mammals, 
which ...