Cumbia might be the original crossover genre. Originating within the Afro and indigenous diaspora of the Caribbean coast of Colombia and Panama, the rustic style started lighting up slums with its infectious dance rhythms in the early 1800s; these days it's as likely to be piped through a high-end resort. Often driven by guiros and accordions, the tropical genre achieved global popularity in the mid-20th century thanks to a compelling sonic diversity that keeps its intoxicating rhythm intact. Raw, playful and dense, Colombia's vallenato is one of its earlier spin-offs. The style became grittier and more lyrically cunning in the streets of Mexico, where DJs dubbed it sonidera. Influenced by psychedelic rock and rooted in Amazonian folklore, Peruvian cumbia is a trippy affair known as chicha. And the irreverent bad boys of Argentina made cumbia villera ("slum cumbia") sound mischievous by plugging in the synths and turning up the sardonic banter.