Are lemurs' low basal metabolic rates an adaptation to Madagascar's unpredictable climate?

It has been argued for nearly two decades that lemurs' low basal metabolic rate (BMR) by comparison to other primates is an adaptation to Madagascar's unpredictable climate. However, data from two recently published studies show that it is not just lemurs, but all strepsirrhines (the Suborder to which lemurs belong), that have low metabolic rates by comparison to other primates. Therefore, the better comparison to substantiate the argument is one with other strepsirrhines, not with all other primates. Data from the two studies do not allow the conclusion that lemurs' BMR is lower than that of other strepsirrhines.