Present-day genetic correlations and testing the aerobic capacity model.

A recent article by Nespolo and Roff suggests that present-day genetic correlations between resting and maximal metabolic rate do not provide support for the aerobic capacity model for the evolution of endothermy. That conclusion is potentially misleading. The aerobic capacity model makes exacting predictions about genetic architecture. While the presence of a genetic correlation does not support the model per se, the absence of a correlation definitively falsifies the model. Testing for present-day correlations remains a useful endeavor, at least until the model is convincingly falsified or until many attempts to falsify the model fail.