The 1513 portrait "An Old Woman" by Flemish artist Quinten Massys might well be one of the Renaissance's most famous paintings. It is also one of the period's most atypical.

With wrinkled skin, withered breasts, and eyes set deep in their sockets, Massys' subject — believed to be either a fictional folkloric character or a woman suffering from an exceptionally rare form of Paget's disease — is visibly elderly. But she's not just old; she's grotesque. Her forehead is bulging, her nose snub and wide, her squared chin overly prominent. Even her attire is a far cry from what you'd expect a Renaissance lady her age to wear. Rather than modest, sober clothes, she's donning a revealing low-cut dress showing off her décolleté (and those dimpled breasts).