“He won’t eat anything but cornflakes,” complained the mother of a boy I used to know. Breakfast, lunch, dinner — always a bowl of cornflakes and milk. Even at other people’s houses, he made no concessions. To his mother, his extreme diet was a source of worry and exasperation. To the rest of us, he was a fascinating case study. Where did it come from, this bizarre cornflake fixation? It just seemed to be part of his personality, something no one could do anything about.
Whether you’re a child or a parent, the question of “likes and dislikes” is one of the great mysteries. Human tastes are astonishingly diverse and can be mulishly stubborn. Even within the same family, likes can vary dramatically from person to person. Some prefer the components of a meal served separate and unsullied, with nothing touching; others can fully enjoy them only when the flavors mingle in a pot.
Because our tastes are such an intimate part of our selves, it’s easy to make the leap to thinking they must be mostly genetic: something you just have to accept as your lot in life. Parents often tell children their particular passions place them on this or that side of the family — you got your fussiness from your grandfather! — as if you were destined from birth to eat a certain way.
The question remains to what extent we can override this genetic inheritance and learn new tastes. This riddle can seem impossible to unravel, given children don’t learn to eat under laboratory conditions. As we take our first bites, our parents supply us simultaneously with both nature (genes) and nurture (environment in its broadest sense, including everything from cuisine to family dynamics to religion to cutlery and table manners to the ethics of meat to views on whether it’s acceptable to eat food off the floor if it was there for only five seconds). The two are so intertwined, it’s hard to tell where one starts and the other stops.
In one remarkable experiment, however, a group of children did learn to eat under lab conditions. In the 1920s and ’30s, Clara Davis, a pediatrician from Chicago, spent six years trying to study what children’s appetites would look like if allowed to blossom without any preconceived ideas of what tasted good. Davis’ results have often been taken as a clear indication that likes and dislikes are fundamentally built-in and natural, though, as we’ll see, Davis herself drew a rather different conclusion.