Waimanu is a genus of early penguin which lived during the Early Paleocene soon after the Cretaceous–Paleogene extinction event. Its discovery helped support the idea that the radiation of the Neoaves (including most modern birds) either took place before the extinction of the non-avian dinosaurs, or extremely rapid in geological terms immediately after. DNA-studies, e.g., the extensive one by Hackett and colleagues, seem to indicate the latter. While it was a very early member of the sphenisciformes (the order that included modern Penguins), Waimanu was flightless like all modern penguins. Though its wing bones do not show the extreme specializations modern penguins have for an aquatic lifestyle, it does seem adapted for wing-propelled diving, and may have resembled a flightless loon in b