XVI International Botanical Congess

The Late Paleocene-Early Eocene interval is characterized by a long period of global warming that culminated with the highest temperature of the last 65 million years. This time interval is associated with an extinction and subsequently increases in plant diversity in mid and high latitudes. However, data from tropical regions remain largely unknown. A detailed palynological survey of a Late Paleocene-Early Eocene section was carried out in central Colombia. Fifty samples were analyzed for pollen/spores content. More than 300 species were found, 50% were restricted to the Eocene, 25% restricted to the Paleocene, and only a 25% occur both in Paleocene and Eocene strata, suggesting a major floral turnover at the Late Paleocene-Middle Eocene interval. The pollen/spores diversity increased during the Early and early Middle Eocene reaching levels higher that those of the Late Paleocene. This increase in diversity may be correlated with the Eocene Thermal Maximum. This demonstrates that the Paleogene warming may have played an important role in paleotropical plant diversity.