Energy efficiency in motion and thought

Simon Sponberg’s article (Physics Today, September 2017, page 34 ) addresses important topics in the physics of insect locomotion in terms of muscle motion, sensing, and information processing. However, one especially important and astonishing aspect of physics, common to living objects and unattainable by manmade machines, is the energy efficiency in both muscle motion and information processing. One impressive example is the energy consumed by the human brain in playing Go or chess with a supercomputer. Although humans now lose both games, the energy consumed by the human brain while playing is five to six orders of magnitude less than that of the supercomputer. ¹