Not that hot after all: no limits to heat dissipation in lactating mice selected for high or low BMR

Heat dissipation has been suggested as a limit to sustained metabolic effort, e.g. during lactation, when overheating is a possible risk. We tested this hypothesis using mice artificially selected for high (H-BMR) or low (L-BMR) BMR that also differ with respect to parental effort. We used fixed sized cross-fostered families and recorded litter mass daily until the 14th day of lactation. Midway through the experiment (day 8th) half of randomly...