He describes Southern Athabascan music, that of the Apache and Navajo, as the simplest next to the Great Basin style, featuring strophic form, tense vocals using pulsation and falsetto, tritonic and tetratonic scales in triad formation, simple rhythms and values of limited duration (usually only two per song), arc-type melodic contours, and large melodic intervals with a predominance of major and minor thirds and perfect fourths and fifths with octave leaps not rare. Peyote songs share characteristics of Apache music and Plains-Pueblo music having been promoted among the Plains by the Apache people.