The accrued palynological data obtained from the subsurface sediments of South Kerala Sedimentary Basin have been found to be useful for identifying various ecological complexes and their environmental preferences. The occurrence and relative abundance
of Cullenia exarillata pollen along with other wet evergreen
forest members at certain intervals are of great significance as they indicate the prevalence of heavy rainfall during Early Holocene. This aspect is further complemented by the presence of a large number of fungal remains. In contrast, their scarcity and even absence at higher levels in boreholes point towards
relatively dry climate during Late Holocene.