Panbiogeography, originally proposed by the French-Italian scholar Léon Croizat (1894–1982) in 1958, is a cartographical approach to biogeography that plots distributions of a particular taxon or group of taxa on maps and connects the disjunct distribution areas or collection localities together with lines called tracks , regarding vicariance as the primary mechanism for the distribution of organisms rather than dispersal. While Panbiogeography influenced development of modern biogeography, the ideas in their original form are not considered mainstream biogeographical theory, and the theory was described in 2007 as "almost moribund".