A macaroni penguin at Cape Bougainville in the Falkland Islands. Vicki Jauron, Babylon and Beyond Photography via Getty Images

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Some pretty tough muscles lay beneath the macaroni penguin’s ( Eudyptes chrysolophus ) somewhat goofy exterior. These small penguins from the islands and waters of the South Atlantic Ocean are known for their distinctive bright-yellow plumes . They are also built for powerful and efficient movement for both walking and swimming, according to a study recently published in the journal The Anatomical Record .

Since penguins don’t fly through the air like most birds , they’ve evolved to fly through the water instead. For macaroni penguins, their key wing muscles look different than in flying birds. For example, a muscle responsible for lifting the wing called the supracoracoideus is much larger in penguins.…