Ah! Now I see what was meant. But I disagree. There are similarities at the beginnings of the two tunes, both melodically and harmonically; but they branch off radically. After all, it is rhythm that distinguishes many melodies from one another, since the pitch and harmonic possibilities are restricted. Someone once said genius only becomes evident after the first several bars of a tune. (See my home page on this very issue.) What Riders in the Sky does with its material is much more interesting than what WJCMH does with its. Very few melodies would be "original" if we ignored "rhythm."