Beautiful as they are, a peacock’s feathers serve a very practical purpose. They have evolved over millennia as a visible sign of mating fitness. A peahen, simply by looking at the splendor of the peacock’s tail, can gauge the health and desirability of that individual as a potential mate. A simple visual clue that provides a reliable measure of underlying soundness.
Blow into this, please
In almost all countries, drunk driving is an offense, enforced through a breathalyzer test. There is a set blood alcohol limit that defines criminal activity. This limit has gradually been getting lower over time. It was originally set at 0.15% in the USA in the 1940s—equivalent to an astonishing eight pints of beer. It’s now far lower—typically 0.05%, for example, in most of Europe. Below that level, a driver may be impaired but not to an extent that is held to be irresponsible. Criminality is a question of degree.