Folks have been "borrowing" melodies for ages, from Bach to John Lennon. But perhaps the most outrageous steal involves today's post subject. The Big Three - an early sixties folk group consisting of Mama Cass, Tim Rose, and Jim Hendricks - took Stephen Foster's Old Susanna and wrote an entirely different melody and harmony, calling it The Banjo Song. So give a listen and be amazed at how not just the melody, but even the guitar lick was reused for a chart-topping hit from 1969. I am not naming names but every person alive over 45 should figure it out quickly.
And I have to say that it is wonderful to discover new music (to me) with Mama Cass's great voice.