SOPP339: How do you develop "melodik ohr"?

This question was sent by Irineo, and he wrote: Splendid/illustrative podcast, maestros. Great guns. But I think maestro Rob left something missing: One of my teachers many years ago told me "if you possess what's called a 'melodic ore', you have an advantage over those who don't". My questions are: 1-How can you teach students to develop that "ore"? 2-Where does it originate? 3-Are some people just born with it? 4-If not, is it possible at all to teach those who don't possess it how to develop it, you think? Irineo