The Emperor penguin (Aptenodytes forsteri) is highly adapted to survive the extreme cold of the Antarctic winter, where wind-chill temperatures can drop below −60∘C-60^\circ\text{C}−60∘C.
Emperor penguins are much larger than equatorial penguins, with some adults weighing up to 40 kg40\text{ kg}40 kg. Explain how having a large body size helps the Emperor penguin to survive at very low temperatures.
These penguins have an extremely dense outer layer of overlapping feathers and a thick subcutaneous layer of blubber. Suggest how these features help them to survive.
The muscles that operate the feet and flippers of polar birds are located deep within the warm body core rather than in the extremities themselves, connected to the joints by long tendons.
Suggest how this physiological arrangement benefits the animal.
Suggest one mechanical property that these long tendons must have.
During severe blizzards, Emperor penguins frequently huddle closely together in giant groups of hundreds of individuals. Explain how this behaviour is an advantage.