I've known about this since the 1990's.
Which of course makes perfect sense because they domesticated every single major animal species in use today and were herders from about 300,000 years onwards. The Neanderthals domesticated the horse over a quarter million years ago and were likely using them in herding for ten times the length of the entire history of Homo Sapiens. Herding peoples start by using flutes and whistles to call their flocks and soon thereafter discover the possibilities of music in such devices.
Note that the diatonic scale implies a long standing structure of songs and music that were transmitted from generation to generation, or else why develop structured sound waves based on a scale most pleasing to the human ear.
Abel was a herder. His brother Cain murdered him because he resented the fact his brother's offering was acceptable to God but he was rejected. Scripture tells us that Cain then pretended he did not know what had happened to his brother when asked. "He must have failed to adapt," he said to God. "He must have committed suicide because his brow stuck out too far. At least according to my skull reconstruction it did."