“…a,b (With 1 figure) Amazon watersheds are a complex ecosystem: the interaction between terrestrial and aquatic ecosystems and the water level fluctuations are the main forcing function that regulates the biodiversity, the evolutionary processes and the interaction between terrestrial and aquatic biota in the large internal deltas, the extensive floodplains regions and the network of channels, creeks, rivers, meanders and lakes (Haffer, 2008). Chemical and physical environment resulting from the inundation periods and the forest, promotes a chain of morphological, anatomical, physiological, geological and ethological adaptations with its characteristics structures (Junk et al, 1989;Alho, 2008).…”