Stadials and interstadials are phases dividing the Quaternary period, the last 2.6 million years. Stadial are colder periods and interstadials are warmer. Each phase has a Marine Isotope Stage (MIS) number, working backwards from the present, with stadial having even numbers and interstadials odd numbers. Thus the current Holocene is MIS1 and the most recent ice age is MIS2. Stages are divided into warmer and colder intervals. MIS 5e (the Eemian), the hottest of the last million years, was the oldest interstadial of MIS5, with MIS3 and MIS1 being interstadials and MIS2 and MIS4 being colder stadials. In glacials a and c are stadials and b and d are warmer interstadials. Thus MIS 6a, 6c and 6e are stadials and 6b and 6d are interstadials.