Micronesia was initially settled from at least three quite separate points of origin and comprises multiple cultural and linguistic stocks. It nevertheless manifests a striking uniformity in its sociopolitical organization. I argue that these shared aspects of Micronesian societies diffused out of the Eastern Caroline Islands as a consequence of a prehistoric sociocultural efflorescence driven at least in part by the hybridization of two entirelydifferent breadfruit species. The characteristic form of Micronesia's dispersed conical clans was spread throughout the entire region, carriedalongwiththe economic successes conferred by productive new breadfruit varieties. Botanical, linguistic, archaeological and ethnological data are marshaled to substantiate this argument.Although Micronesia constitutes a coherent geographic region, it is sometimes dismissed as having little or no validity as an ethnological concept. Archaeological and linguistic evidence make it clear that the eastern and western reaches of the area were initially settled by different peoples moving out of distinctly different homelands, probably at different times. It is primarily because of these disparate origins, as compared, say, to the relative homogeneity of the Polynesians, that the existence of a valid Micronesian culture area is denied, although other sociocultural differences have also been cited (