Clarkforkian

The Clarkforkian North American Stage, on the geologic timescale, is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 56,800,000 to 55,400,000 years BP lasting 1.4 million years.[1]

Considered to be within the Paleocene, more specifically the Late Paleocene, the Clarkforkian shares its upper boundary with the Thanetian.

The Clarkforkian is preceded by the Tiffanian and followed by the Wasatchian NALMA stages.

Substages

It is considered to contain the following substages:

  • Cf3: (shares the upper boundary) and lower boundary source of the base of Clarkforkian (approximate) and upper boundary source of the base of the Ypresian (approximate).
  • Cf2: Is the lower boundary source of the base of the Clarkforkian (approximate)
  • Cf1: Upper boundary source of the base of the Ypresian (approximate)

Fauna

Notable mammals[2][3]

Multituberculata - non-therian mammals

Metatheria - marsupials

Carnivora - carnivores, including living carnivorous mammals

Condylarthra - archaic ungulates

Creodonta - extinct group of carnivorous mammals

Dinocerata - large, tusked herbivores

Eulipotyphla - insectivorous mammals

  • Plagioctenodon, nyctitheriid insectivore
  • Wyonycteris, nyctitheriid insectivore

Mesonychia - carnivorous hoofed mammals

Pantodonta - large herbivorous mammals

Primatomopha - primates and relatives

Rodentia - rodents

Tillodontia - medium sized, digging herbivores

  • Esthonyx, esthonychid tillodont
gollark: You're welcome. As payment I request 1 (one) zettosoul.
gollark: "E-books" contain text and images similarly to a normal book, but as digital information rather than paper.
gollark: Of course, in the interweb era™ "book" has become somewhat generalized, and often refers to the content itself, as this can be shipped as an "ebook".
gollark: <@213674115700097025>
gollark: Books:- mostly used to refer to objects of bound paper with covers (covers can be various materials, often card/harder paper)- paper inside the book ("pages") typically contains information about a topic encoded as patterns of ink on them- topics can include someone's notes on a subject, or something intended for wider distribution/other people such as a story/set of stories ("fiction") which did not really occur, or true information ("non-fiction")- cover generally contains art related to the contents, as well as what the book is named ("title") and who wrote it ("author")- the back will often contain a "blurb" describing the contents somewhat, as well as potentially reviews by others

References
  1. Paleobiology Database, Clarkforkian
  2. "The Clarkforkian Land-Mammal Age and Mammalian Faunal Composition Across the Paleocene-Eocene Boundary". hdl:2027.42/48626. Cite journal requires |journal= (help)
  3. Wilf, Peter; Beard, K. Christopher; Davies-Vollum, K. Sian; Norejko, Jay W. (December 1998). "Portrait of a Late Paleocene (Early Clarkforkian) Terrestrial Ecosystem: Big Multi Quarry and Associated Strata, Washakie Basin, Southwestern Wyoming". PALAIOS. 13 (6): 514. Bibcode:1998Palai..13..514W. doi:10.2307/3515344. ISSN 0883-1351. JSTOR 3515344.


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.