Even if we want to think of the Pleistocene as the important Ice Age, we still need to dispel some common misconceptions. It lasted from about 2,588,000 to 11,700 years ago and was not a period of constant cold. True enough, it was a time of repeated glaciations, but these were mixed with much warmer periods. We should think more in terms of repeated rapid climate change. For more than 2 million years, the climate flipped between cold and warm, with the shift between them sometimes much less than a century. The change could be short enough for an individual to notice the variation in climate during their lifetimes.