Sorry, inherently hard to find again again on google, so no links, but I remember 2 different studies, one in Central- or Eastern Africa and another in the Amazon rain forest: People who where never exposed to harmonic music don't have an innate preference for harmonies over disharmonies. IIRC they preferred whatever was closest to what they knew, which was interpreted as a clue that music perception is heavily influenced by the expectations of the listeners.
In context, "have octaves" mean treating notes whose frequencies are powers of two as the "same", just shifted up. I believe the pentatonic scale still has this feature.