Séminaire de groupe
|Paleontology in Venezuelan Tar pits|
|Ecologie - IVIC - Caracas|
|jeudi 06 septembre 2012 , 10h25|
|Salle de séminaire du groupe de Physique Statistique|
South America was an isolated continent by 65 million years, but 3 to 4 million years ago, this continent was connected by a land bridge with North America, originating a biotic flow between both Americas. We called this fact The Great American Biotic Interchange (GABI), this phenomenon was the responsible of the modern ecosystems because this allowed the interaction of two very different bioregions, and creating a biogeographical balance until originated the modern biomes of America. We are studying two localities in Venezuela (Northern South America) where we have been found evidences of the GABI. Also we are working on paleoenvironmental hypothesis for both sites. Mene de Inciarte and El Breal de Orocual localities have a common feature; both are deposited on tar seeps. Tar seeps are a very helpful tool to reconstruct past environments because they catch every organism, which pass over its surface, and this could became a fossil. They are a record of the past life on the area where they was. We have been interpreted Mene de Inciarte (27 thousand year old, in Zulia State) as a savanna with patches of trees environment and El Breal de Orocual (2,8 to 0,5 millions years old, in Monagas State) as a shrub savanna with trees. El Beral de Orocual could be represents the beginning of the GABI, and Mene de Inciarte the end of the GABI.