Ostracodes and pollen preserved in a 75.9-m-long sediment core (PI-6) recovered from Lake Petén Itzá, Guatemala were used to assess the magnitude and velocity of aquatic and terrestrial community responses during the last 85,000 years. Our ostracode data (adults and juveniles) includes information on Detrended Correspondence Analysis (DCA) species scores along the first two DCA axes, stratigraphic DCAs (axes 1 and 2), ecological change and rates of ecological change. The following pollen data are provided as well: DCA taxa scores along the first two DCA axes, stratigraphic DCAs (axes 1 and 2), ecological change and rates of ecological change.