North American Land Mammal Ages

The interval definitions in this timescale are derived from the following sources:

  • A. D. Barnosky, M. Holmes, R. Kirchholtes, E. Lindsey, K.C. Maguire, A.W. Poust, M.A. Stegner, J. Sunseri, B. Swartz, J. Swift, N.A. Villavicencio and G. Wogan. 2014. Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs). The Anthropocene Review I(3):225-242 view
  • M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
  • J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 view

There are 13 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

This timescale is used in the definition of 7507 collections

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International Chronostratigraphic TimescaleNorth American Land Mammal AgesNorth American Mammal Subages/Zones
QuaternaryHoloceneMeghalayanSaintaugustinean0
Santarosean0.0004
Northgrippian0.0042
Greenlandian0.0082
PleistoceneLate PleistoceneSheridanian0.0117
Rancholabrean0.014
Chibanian0.129
IrvingtonianCudahyan/Sappan0.21
Calabrian0.774
BlancanSenecan/Rexroadian1.4
Gelasian1.8
NeogenePliocenePiacenzian2.58
Zanclean3.6
HemphillianLate Hemphillian/late Early Hemphillian/early Early Hemphillian4.7
MioceneMessinian5.333
Tortonian7.246
ClarendonianLate Clarendonian/Early Clarendonian9.4
Serravallian11.63
Barstovianlate Late Barstovian/early Late Barstovian/Early Barstovian12.5
Langhian13.82
Burdigalian15.98
HemingfordianLate Hemingfordian/Early Hemingfordian16.3
Arikareeanlate Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonian18.5
Aquitanian20.44
PaleogeneOligoceneChattian23.03
Monroecreekian23.1 *
Geringian24.7 *
Rupelian27.82
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronianLate Chadronian/Middle Chadronian/Early Chadronian33.9
Duchesnean37
Bartonian37.71
UintanLate Uintan/Early Uintan39.7
Lutetian41.2
BridgerianTwinbuttean/Blacksforkian/Gardnerbuttian46.2
Ypresian47.8
WasatchianLostcabinian/Lysitean/Graybullian/Sandcouleean50.5
ClarkforkianCf3/Cf2/Cf154.9
PaleoceneThanetian56
TiffanianTi6/Ti5/Ti4/Ti3/Ti2/Ti156.2
Selandian59.2
TorrejonianTo3/To2/To160.9
Danian61.6
PuercanPu3/Pu2/Pu163.8
66