For decades, baby bottles have been cylindrical—a design that, while functional, can be confusing for breastfed infants and problematic for parents who need to heat milk quickly and evenly.

THE HOOD MILK BOTTLE JUST OUTSIDE THE BOSTON CHILDREN’S MUSEUM ON FORT POINT CHANNEL. I REMEMBER THE FIRST TIME I SAW IT, I THOUGHT, WHAT IS THIS? AND I THINK THAT’S THE REACTION A LOT OF ...