The bigger the animal is, the lower its surface-to-volume ratio; for every ounce of body mass, there is proportionately less surface through which heat can escape.
动物体型越大，其体表体积比越低；躯体每增加一盎司的重量，所能散发热量的表面就成比例减少。
3
And in practical terms, we can define the efficiency as the ratio of the heat in to the work out.