Seeing rats, lemmings, mice and dormice score highly makes me think that the consumption of calories per unit of weight due to their basal metabolism has not been discounted, which is very high in small mammals. Seeing the scores of large marine mammals and reptiles would be enlightening, since the water suppor makes more efficient the transport in one case, and their metabolism is much lower in the other.
Obviously, the comparison with machines is absurd, since their consumption when stationary is zero.