Researchers traveled to Antarctica and put 10 king penguins on a treadmill. They found fat king penguins are more unsteady on their feet while waddling compared to their slimmer counterparts. – WTF Fun Facts
Source: https://www.theguardian.com/science/2016/feb/25/penguins-on-a-treadmill-study-shows-fat-ones-fall-over-more-often-than-slim-ones
