A study showed that penguins burn twice as many calories when walking than do animals of a similar size. It was assumed that this high energy expenditure was due to the way penguins waddle. In a paper published in December in the journal, Nature, two scientists reported a new finding about the penguin waddle. By coaxing penguins across a platform that measures force, the scientists were able to determine that the waddle actually helps penguins conserve energy. Just as a pendulum stores energy at the end of one swing to help fuel the next swing, a penguin maximizes the use of its energy expenditure by waddling from side to side.
Short muscles have to work harder than long muscles in order to generate force for walking.
According to the new study, a penguin uses about the same number of calories in walking as do animals with legs of similar length. In order to understand how the waddle conserves energy, students need to learn about pendulum-like motion and the variations of kinetic and potential energy during periodic motion. The study showed that short legs cause a penguin to burn more calories when walking than animals of a similar size. Yet short legs must benefit penguins somehow, or evolution would have provided them with longer legs. Extending the Problem Penguins have been in the news for other reasons.