Repeatability of metabolic rate is lower for animals living under field versus laboratory conditions
ABSTRACT Metabolic rate has been linked to several components of fitness and is both heritable and repeatable to a certain extent. However, its repeatability can differ among studies, even after controlling for the time interval between measurements. Some of this variation in repeatability might be due to the relative stability of the environmental conditions in which the animals are living between measurements. We compared published repeatability estimates for basal, resting and maximum metabolic rate from studies of endotherms living in the laboratory with those living in the wild during the interval between measurements. We found that repeatability declines over time, as demonstrated previously, but show for the first time that estimates from free living animals are also considerably lower than those from animals living under more stable laboratory conditions. Summary: Individual metabolic rates are generally repeatable, but repeatability not only declines with time interval between measurements but is also lower for animals living under field versus more stable laboratory conditions.
Journal of Experimental Biology