Sentence:  Scales have proliferated like <WSD>tribbles</WSD> in quadra-triticale: just intonations, equal temperaments, scales based on overtones, scales generated from a single interval or pair of intervals, scales without octaves, scales arising from arcane mathematical formulas, scales that reflect cosmological or religious structures, scales that "come from the heart." 
Meaning of the word marked with <WSD> tags:  A fictional alien creature in "Star Trek", a fast-breeding, cooing ball of fur.