La evolución de las comunidades de moluscos y su relación con el desarrollo geológico del sur de América Central

Abstract

Mollusks fossil communities found in southern Central America developed in accordance to tectonic, and hence favorable environmental conditions of the Isthmus evolution. The initial stage of the island arc, during the Late Cretaceous, determined the appearance of rudistic bioherms on the shallow platforms surrounding the islands. Later, during the Early Tertiary the predominance of deeper sedimentary environments and the intense volcanic activity restricted the mollusks populations to rather small groups. During the Oligocene to Miocene, the island are evolved to a number of island of greater area separated by narrow channels. This provided an appropiate environment for the development of homogeneous malacological faunistic communities with high diversity of species. The final uplift of the Central America isthmus during the Pliocene stopped the faunistic interchange between Pacific and Caribbean communities which decrease diversitifation of species at the Caribbean side