I am sure I have ranted about the negative effects of DST here and back on Circadiana, but the latest study – The Human Circadian Clock’s Seasonal Adjustment Is Disrupted by Daylight Saving Time (pdf) (press releases: ScienceDaily, EurekAlert) by Thomas Kantermann, Myriam Juda, Martha Merrow and Till Roenneberg shows that the effects are much more long-lasting and serious than previously thought. It is not “just one hour” and “you get used to it in a couple of days”. Apparently it takes weeks for the circadian system to adjust, and in some people it never does. In this day and age of around-the-clock life, global communications, telecommuting, etc., the clock-shifting twice a year has outlived its usefulness and should go the way of the dodo. The research also shows why studies of photoperiodism is not some arcane field, but has real-world applications.