A monocle is a jewellery piece with a retractable mechanism hidden inside its silver body. Considering the realm of design in the context of Cultural Darwinism, we have to concede that this kind of eyewear has some distinguishing features which ensure its survival in a jungle of jewellery manufacture:
1 - A customer buys one item, but owns two;
2 - The eyewear is hard to misplace as it rests on an ear;
3 - The owner is ever in the spotlight;
4 - Simple magnetic connector gives earing evolutionary advantage to be transformed into glasses.