Truffles smell of sex. Even if we can’t quite say what we mean by ‘smell’ or ‘sex’ in this sentence, the much sought-after underground fungi emit something analogous to the pheromones that subconsciously attract us to other human beings. On the conscious level, these members of the family Tuberaceae release aromas ranging from floral to garlic to petrol to old socks, which pigs and dogs also find appealing.