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　　When a penguin walks, its tall, narrow body acts like a pendulum. Kinetic energy builds up with each step the bird takes. As the penguin takes its next step, that kinetic energy isn’t wasted, but instead helps carry the bird forward. The kinetic energy is what causes penguins to sway forwards and backwards, and from side to side. Much like a bowling pin that wobbles back and forth yet doesn’t fall, a penguin’s body is carried forward by kinetic energy.

　　This highly functional walking style allows penguins to save roughly eighty percent of the mechanical energy they use while walking. While it is a certainty that waddling does burn a lot of calories, the penguins actually save energy in the long run because kinetic energy helps to keep them moving forward. So before laughing the next time you observe a penguin walking, remember that waddling isn’t just for the birds. In fact, it far more efficient than your own way of walking!