© Steve Maslowski, U.S. Fish and Wildlife Service.
Hummingbirds, like the one pictured here, exemplify several areas of biological physics at once. Their mechanical properties are remarkable, especially their wings, with a high beat rate and large range of motion lending themselves to flight of which most airplane pilots can only dream. Their mental acuity is also impressive. Hummingbirds remember each flower they visit and calculate when the nectar supply is likely to be replenished, and need neither maps nor GPS to navigate accurately over thousands of miles. If we assume that the brain can be modeled as a computing machine, it's an open question how a pea-sized computer can accomplish so much. (Unit: 9)