Explain why very small animals are rarely found in polar region.

• For small animals, thermoregulation is a very expensive process.

• Heat loss or heat gain is a function of surface area which is directly proportional to it.

• Compared to their volume, small animals have a larger surface area.

• Therefore, they lose body heat very fast in a colder region, so they have to expend more energy to generate body heat which becomes a challenge for their survival.

• This is the main reason why very small animals are rarely found in polar-regions.