The final style of Chinchorro mummification was the mud-coat (3000-1300 BCE). Ecologically speaking, at the time of the Chinchorro culture the region was relatively stable. It has been suggested by environmentalists that the incredible preservation of these mummies is also influenced by the pedogenic (the evolution of soil) creation of clays and gypsum, which act as cementing agents, and the latter as a natural desiccant. The malleable clay allowed for the morticians to mold and create the colorful appearances of mummies, with the added bonus of the fact that the foul smell of the desiccating mummy would be covered. Artisans no longer removed the organs of the dead; instead a thick coat of mud, sand and a binder like egg or fish glue was used to cover the bodies. Once completed the mummies were cemented into their graves. The change in style may have come from exposure to outsiders and their different cultures, or from the association of disease with the rotting corpses.