The Danian is the oldest age or lowermost stage of the Paleocene epoch or series, the Paleogene period or system and the Cenozoic era or erathem. The beginning of the Danian age (and the end of the precessing Maastrichtian age) is at the Cretaceous-Tertiary extinction event 65.5 ± 0.3 Ma (million years ago). The age ended 61.7 ± 0.2 Ma, being followed by the Selandian age. Stratigraphic definitions The Danian was introduced in scientific literature by German-Swiss geologist Pierre Jean… (More on Danian)