Fascinating Facts

The Rat and the Elephant

The living cell of almost all mammals perform similar functions, therefore the energy reqirement should also be the same. Yet a rat consumes several times more energy per gram body weight than an elephant. How can this be explained?

If a single cell is considered the energy requirement is the same for almost all mammals. If the entire organism is considered the rat has a a larger surface area per gram body weight than an elephant. The heat loss due to radiation therefore is much more in the case of a rat. Thus to maintain the body temperature the rat needs more energy.