Abstract: <p>The length of photoperiod can alter circadian rhythms and change fat depot mass whencombined with environmental temperatures below thermoneutral. To isolate photoperiod effects, we compared the effects of long and short photoperiod exposure at thermoneutrality in photoperiod sensitive, F1 generation adult male white-footed mice (P. leucopus). Mice were housed in long-day or short-day… more