Penguins live in Antarctica because they are especially adapted to the cold through their unique feathers, small feet and circulatory system. For instance, one of the species that lives in Antarctica, the emperor penguin, has an especially small bill and feet that help it to conserve heat.
According to the Australian Department of the Environment, emperor penguins have many adaptive features that enable them to thrive in the cold of Antarctica. Its feathers are very small and scale-like, layering the penguin underneath plenty of insulation. This insulation also includes large amounts of body fat. The veins and the arteries of the penguin's circulatory system are close together, which helps the bird to recycle its body heat. Biology aside, penguins are very sociable and huddle together, which conserves heat during the Antarctic winters.
However, not all species of penguins can survive in Antarctica. Of the dozens of species that populate the world, all of which reside in the Southern Hemisphere, only two can survive in the cold of Antarctica: the emperor penguin and the adelie penguin. In fact, it is the Antarctic winter that is also the mating season of the emperor penguin. Upon laying a single egg, the females go hunting for the next two months while the males stay with the eggs.