Today is the Feast day of Saint Rock or, as he is familiarly known, Saint Rocky. Saint Rocky is the Patron Saint of Dog Lovers, having been kept alive in the wilderness when he was sick by a dog who brought him bread every day from his master's table. 

St. Rocky got sick tending the plague-stricken and though the plague did not kill him, thanks to Fido the Faithful, it made him so unrecognizable that when he arrived home in Montpellier, he was thrown in jail as an impostor. When he died, his jailers found a birthmark that proved his identity. Why they did not think to look for the birthmark while he was alive remains a mystery.

It is hard to imagine a dog being caught so long by a case of mistaken identity. Smell is not so deceptive, I think, as sight. Sure, diet and health can change the overtones, but out genetic code gives us our basic smell. Even humans with their comparitive dearth of olfactory information processing, it turns out, can read genes by sniffing. Co-eds in a college experiment got to smell men's t-shirts, and chose as smelling "sexy" the shirts worn by guys whose genetic profile meant an immune system that complemented their own, and as "dull" the shirts of guys whose were the most genetically similar. "He smells like my brother" was a comment that was genetically accurate. The nose knows more than we think.