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During the Paleocene, about 60 million years ago, the earth´s temperature was about 10°C higher than today. Several transient warming events as the Paleocene-Eocene Thermal Maximum (PETM, 56 million years ago) and the Latest Danian Event (LDE, 62.14 million years ago) rose the temperatures even higher. These warming events (or hyperthermals) took place due to several causes: 1. methane release by a change in ocean water circulation, 2. mantle plume volcanism at North Atlantic Igneous Provinces emitting CO2 gasses, and 3. a variation in the Milanković variables (eccentricity of earth’s orbit, axial tilt and axial precession of the earth) changing the intensity and distribution of sun insolation. In the LDE, the deep ocean and surface water warmed up additionally with respectively 1.6-2°C and 2.8°C. Temperature reconstruction and the recognition of these climatic events can be conducted by carbon and oxygen isotope studies in foraminifera (unicellular organisms with a calcareous test). δ13C and δ18O show both negative values during a warming event, due to the input of light 12C isotopes in the ocean and the preference of foraminifera to take up less of the heavy oxygen 18O isotope in their skeleton. Besides these geochemical measurements, a geological event is also recorded in sediments by characteristic lithology. A popular example is the Chicxulub asteroid impact at the Cretaceous/Paleogene boundary which is recognized by an ejecta rich deposit of iridium in the clay on an almost global scale. Also, biotic changes in the fossil record help to locate and date events in geological history. Planktic foraminifera are useful due to the fast evolution of distinctive species and widespread occurrence in marine sediments. The first and last appearance of a species can function as geological marker for an event, but reworking of material by other organisms (e.g. burrowing) may bring older fossils up and relocates the time marker. A more reliable marker is provided by the use of consistent appearances rather than focus on the ultimate first or last species in the record. The geological timescale units are correlated with rock strata, sea level changes, climate, geological events and the fossil record. In the planktic foraminifera Zone P3, which is in the Paleocene, the LDE is currently marked with the first appearance of Igorina albeari. Strikingly, this small biconvex and keeled (rim around test) planktic foraminifera species only correlates to the LDE for the former Tethys Ocean and lower latitudes. For the South Atlantic and Pacific Ocean the first appearance of Igorina albeari is 500.000 years older than the LDE. The last consistent appearance of Praemurica spp. has been defined a better marker for the onset of the LDE. This planktic foraminifera species with pustules, a low trochospiral and globular to ovoid chambers is a more useful marker on a global level based on studies in the former Tethys Ocean, North Pacific Ocean, North and South Atlantic Ocean and Indian Ocean. This revision of planktic foraminiferal Zone P3 is needed.