Approximately 80% of the avian biomass (the total living biological material of a biological community or group in a given area) in Antarctic region is composed of Macaroni penguins (Eudyptes chrysolophus), which are thought to be significant consumers of the marine food resources required by several species including fur seal (Arctocephalus gazelle). Investigators were interested in knowing whether there was a liner relationship between the heart rate (beats/min) of a Macaroni penguin and its metabolic rate (i.e., the mass specific rate of oxygen consumption in ml/min/kg). If there was, they hoped to provide estimates of energy expenditure that could give the investigators an indication of food consumption. They analyzed the data from each of 24 penguins which were exercised on a variable speed treadmill. The estimated correlation coefficient for one of the penguins whose heart rate lay in the range 125-225 beats/min was 0.904 (p < 0.001).

1. How much variation in oxygen consumption can be attributed to its linear relationship with heart rate?