Metabolism Ecology shapes bird bioenergetics

The basal rate of metabolism of birds and mammals is the lowest rate that is compatible with endothermic temperature regulation, balancing the heat generated with the heat lost by the product of thermal conductance and the temperature differential with the environment. Here I measure the bioenergetics of 13 species and 9 genera of birds of paradise (Paradisaeidae) and show that 99% of the variation in their basal rates of metabolism can be accounted for by interspecific variation in body mass, food habits and altitudinal distribution. These findings, which are derived from 31% of the species and 53% of the genera in this family, give the most complete picture of the standard energetics of any diverse family of birds.