Question: Information: - The Selandian is in the geologic timescale an age or stage in the Paleocene . It spans the time between 61.6 and 59.2 Ma . It is preceded by the Danian and followed by the Thanetian . Sometimes the Paleocene is subdivided in subepochs , in which the Selandian forms the '' Middle Paleocene '' . - The Thanetian is, in the ICS Geologic timescale, the latest age or uppermost stratigraphic stage of the Paleocene Epoch or series. It spans the time between . The Thanetian is preceded by the Selandian age and followed by the Ypresian age (part of the Eocene). The Thanetian is sometimes referred to as the Late Paleocene sub-epoch. - The Maastrichtian is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned the interval from . The Maastrichtian was preceded by the Campanian and succeeded by the Danian (part of the Paleogene and Paleocene). - An era is a span of time marked by character, events, changes on earth, etc. When used in science, for example geology, an "era" denotes a clearly defined period of time of arbitrary but well-defined length, such as for example the Mesozoic Era frozen m 252 Ma66 Ma, delimited by a start event and an end event. When used in social history, eras may for example denote a period of some monarch's reign. In colloquial language, eras denote longer spans of time, before and after which the practices or fashions change to a significant degree. When era is extended to a calendar system, it is known as a calendar era. In Sanskrit or Indian culture eras are known as yugas. - In the geologic timescale the Ypresian is the oldest age or lowest stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian age (part of the Paleocene) and is followed by the Eocene Lutetian age. - 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 preceding Maastrichtian age) is at the CretaceousPaleogene extinction event . The age ended , being followed by the Selandian age. - The Paleocene or Palaeocene, the "old recent", is a geologic epoch that lasted from about . It is the first epoch of the Paleogene Period in the modern Cenozoic Era. As with many geologic periods, the strata that define the epoch's beginning and end are well identified, but the exact ages remain uncertain. - In stratigraphy, paleontology, geology, and geobiology an erathem is the total stratigraphic unit deposited during a certain corresponding span of time during an era in the geologic timescale. - The Paleogene (or ; also spelled Palaeogene or Palogene; informally Lower Tertiary) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago (Mya) to the beginning of the Neogene Period Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon. The Paleogene is most notable for being the time during which mammals diversified from relatively small, simple forms into a large group of diverse animals in the wake of the CretaceousPaleogene extinction event that ended the preceding Cretaceous Period. - The Eocene Epoch, lasting from , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope C in the atmosphere was exceptionally low in comparison with the more common isotope C. The end is set at a major extinction event called the "Grande Coupure" (the "Great Break" in continuity) or the EoceneOligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. - The Cenozoic Era (also Cnozoic, Caenozoic or Cainozoic ; meaning "new life", from Greek "kainos" "new", and "zoe" "life") is the current and most recent of the three Phanerozoic geological eras, following the Mesozoic Era and covering the period from 66 million years ago to present day. Given the information, choose the subject and object entities that have the relation of 'subclass of'.
Answer:
selandian , palaeocene