In the early 20th Century, the United States Army labs used an inverted blue triangle, for instance, while the Navy employed a pink rectangle; meanwhile, Universal Postal Convention called for a white staff-and-snake on a violet field for biological transportation. While developing containment systems for dangerous biological materials with the NIH, workers at Dow grew concerned that this lack of universality was contributing to accidental infections of laboratory personnel.

Ecce homo (Behold the man), a 1930 fresco depicting Jesus wearing a crown of thorns, became a global phenomenon four years ago when it was discovered that one of the church’s parishioners, the octogenarian Cecilia Giménez, had attempted to repair the aging artwork by touching up the paint. The result of her work, the BBC correspondent Christian Fraser reported, was that the painting now resembled not the son of God, but a “crayon sketch of a very hairy monkey.”

Popular in countries such as Great Britain, roundabouts are demonstrably more efficient at moving traffic than four-way stops and other types of intersections. Yet in many places, including the United States, they have failed to become widely adopted.