How vermin went from being part of everyone's life to a mark of disease, filth, and lower status. For most of our time on this planet, vermin were considered humanity's common inheritance. Fleas, lice, bedbugs, and rats were universal scourges, as pervasive as hunger or cold, at home in both palaces and hovels. But with the spread of microscopic close-ups of these creatures, the beginnings of sanitary standards, and the rising belief...