“The cozy relationships between natural secretions and savory foods, or accidental emissions and eros, are well known to anyone who has nuzzled the dirty scalp of a loved one, but McGee lays out the molecular evidence for these desires. We might like to think we are most drawn to lovely, “clean” smells—laundry, linden blossoms, a eucalyptus breeze—but more often than not our greatest sensory delight comes from our most intimate, and most odiferous, nooks and crannies.”