1. When turkeys strut, their leg muscles work as shock absorbers to boost energy efficiency. That gam action inspired a prosthetic exoskeleton for humans: The lightweight contraption is outfitted with a spring and clutch that take the impact off the user’s calf muscle. In experiments, a person wearing the braces while walking expended 10 percent less energy. 2. Though it has a brain, the lamprey—an eel-like beast—doesn’t need it to wiggle about the deep.

Learn about your ad choices: dovetail.prx.org/ad-choices