The contribution that conduction makes to the heat loss depends on the thermal conductivity of the materials in immediate contact with the skin. This heat loss occurs when the body parts of penguins come in contact with the ice or snow which is at very low temperature.

Ice and snow are cold. If we lie down on snow, we would be really cold as there would be a large area of contact to lose body heat through conduction. If we stand up, immediately our area of contact reduces enormously. If we stand on tip–toes, our area of contact is reduced to a minimum. This is what penguins do! They rock backwards on their heels, holding their toes up to reduce the area of contact with the snow, to prevent the loss of heat due to conduction. To stop themselves from falling over backwards while holding their toes up, they support themselves by their stiff tail plumage that have no blood flow and so lose no heat. So in the coldest conditions, penguins sit there supported on their heels with reduced blood flow, to keep themselves warm.