An LC at a nearby hospital made a display of artificial teats for her staff. She talked about how they all knew babies could show strong preferences for one teat over another, refusing some shapes altogether; why should anyone think the human nipple would be the only one exempt from preferences, especially since it, too, comes in such a vast array of shapes and sizes. She also talked with them about the effect of a "super-normal stimulus". Some birds will abandon their own eggs in favor of similarly colored but much bigger eggs - or will ignore their own young's gaping mouths in favor of a more brightly colored or wider gaping mouth. They are built to respond to a certain stimulus - and the bigger the stimulus the stronger their response, even if it means the response is totally maladaptive. But then, in a real world, those birds would simply never encounter a super-normal stimulus. It's interference that sets them up for inappropriate responses. In the same way, a baby is at risk of ignoring the normal stimulus in favor of the super-normal stimulus of a bottle teat. I thought her presentation (heard about it; didn't see it) was as logical and persuasive as any I've seen or read. -Diane Wiessinger, LC in private practice, Ithaca, NY