Neogene - wikipedia Neogene `` Neogenic '' redirects here. For the fictional item featured in Marvel comics and animated series, see Neogenic ( comics ). Neogene Period 23.03 -- 2.58 million years ago PreЄ Є O Pg Mean atmospheric O 2 content over period duration c. 21.5 vol % ( 108 % of modern level Mean atmospheric CO 2 content over period duration c. 280 ppm ( 1 times pre-industrial level ) Mean surface temperature over period duration c. 14 ° C ( 0 ° C above modern level ) Key events in the Neogene view discuss edit - 24 -- -- - 22 -- -- - 20 -- -- - 18 -- -- - 16 -- -- - 14 -- -- - 12 -- -- - 10 -- -- - 8 -- -- - 6 -- -- - 4 -- -- - 2 -- -- 0 -- n o z o i Paleogene o g n Quaternary i o n l i o n Aquitanian Burdigalian Langhian Serravallian Tortonian Messinian Zanclean Piacenzian ← Messinian salinity crisis ← Holocene begins 11.7 ka ago An approximate timescale of key Neogene events. Vertical axis : millions of years ago. The Neogene ( / ˈniːəˌdʒiːn / ) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period 23.03 million years ago ( Mya ) to the beginning of the present Quaternary Period 2.58 Mya. The Neogene is sub-divided into two epochs, the earlier Miocene and the later Pliocene. Some geologists assert that the Neogene can not be clearly delineated from the modern geological period, the Quaternary. During this period, mammals and birds continued to evolve into roughly modern forms, while other groups of life remained relatively unchanged. Early hominids, the ancestors of humans, appeared in Africa near the end of the period. Some continental movement took place, the most significant event being the connection of North and South America at the Isthmus of Panama, late in the Pliocene. This cut off the warm ocean currents from the Pacific to the Atlantic Ocean, leaving only the Gulf Stream to transfer heat to the Arctic Ocean. The global climate cooled considerably over the course of the Neogene, culminating in a series of continental glaciations in the Quaternary Period that follows. Contents 1 Divisions 2 Geography 3 Climate 4 Flora and fauna 5 Disagreements 6 References 7 External links Divisions In ICS terminology, from upper ( later, more recent ) to lower ( earlier ) : The Pliocene Epoch is subdivided into 2 ages : Piacenzian Age, preceded by Zanclean Age The Miocene Epoch is subdivided into 6 ages : Messinian Age, preceded by Tortonian Age Serravallian Age Langhian Age Burdigalian Age Aquitanian Age In different geophysical regions of the world, other regional names are also used for the same or overlapping ages and other timeline subdivisions. The terms Neogene System ( formal ) and upper Tertiary System ( informal ) describe the rocks deposited during the Neogene Period. Geography The continents in the Neogene were very close to their current positions. The Isthmus of Panama formed, connecting North and South America. The Indian subcontinent continued to collide with Asia, forming the Himalayas. Sea levels fell, creating land bridges between Africa and Eurasia and between Eurasia and North America. Climate The global climate became seasonal and continued an overall drying and cooling trend which began at the start of the Paleogene. The ice caps on both poles began to grow and thicken, and by the end of the period the first of a series of glaciations of the current Ice Age began. Flora and fauna Scene featuring Miocene ( Early Neogene ) fauna Marine and continental flora and fauna have a modern appearance. The reptile group Choristodera became extinct in the early part of the period, while the amphibians known as Allocaudata disappeared at the end. Mammals and birds continued to be the dominant terrestrial vertebrates, and took many forms as they adapted to various habitats. The first hominids, the ancestors of humans, appeared in southern Europe and migrated into Africa. In response to the cooler, seasonal climate, tropical plant species gave way to deciduous ones and grasslands replaced many forests. Grasses therefore greatly diversified, and herbivorous mammals evolved alongside it, creating the many grazing animals of today such as horses, antelope, and bison. Disagreements The Neogene traditionally ended at the end of the Pliocene Epoch, just before the older definition of the beginning of the Quaternary Period ; many time scales show this division. However, there was a movement amongst geologists ( particularly marine geologists ) to also include ongoing geological time ( Quaternary ) in the Neogene, while others ( particularly terrestrial geologists ) insist the Quaternary to be a separate period of distinctly different record. The somewhat confusing terminology and disagreement amongst geologists on where to draw what hierarchical boundaries is due to the comparatively fine divisibility of time units as time approaches the present, and due to geological preservation that causes the youngest sedimentary geological record to be preserved over a much larger area and to reflect many more environments than the older geological record. By dividing the Cenozoic Era into three ( arguably two ) periods ( Paleogene, Neogene, Quaternary ) instead of seven epochs, the periods are more closely comparable to the duration of periods in the Mesozoic and Paleozoic eras. The International Commission on Stratigraphy ( ICS ) once proposed that the Quaternary be considered a sub-era ( sub-erathem ) of the Neogene, with a beginning date of 2.58 Ma, namely the start of the Gelasian Stage. In the 2004 proposal of the ICS, the Neogene would have consisted of the Miocene and Pliocene epochs. The International Union for Quaternary Research ( INQUA ) counterproposed that the Neogene and the Pliocene end at 2.58 Ma, that the Gelasian be transferred to the Pleistocene, and the Quaternary be recognized as the third period in the Cenozoic, citing key changes in Earth 's climate, oceans, and biota that occurred 2.58 Ma and its correspondence to the Gauss - Matuyama magnetostratigraphic boundary. In 2006 ICS and INQUA reached a compromise that made Quaternary a subera, subdividing Cenozoic into the old classical Tertiary and Quaternary, a compromise that was rejected by International Union of Geological Sciences because it split both Neogene and Pliocene in two. Following formal discussions at the International Geological Congress, Oslo Norway, August 2008, the ICS decided in May 2009 to make the Quaternary the youngest period of the Cenozoic Era with its base at 2.58 Mya and including the Gelasian age, which was formerly considered part of the Neogene Period and Pliocene Epoch. Thus the Neogene Period ends bounding the succeeding Quaternary Period at 2.58 Mya. References Jump up ^ Image : Sauerstoffgehalt - 1000mj. svg Jump up ^ File : OxygenLevel - 1000ma. svg Jump up ^ Image : Phanerozoic Carbon Dioxide. png Jump up ^ Image : All palaeotemps. png Jump up ^ Krijgsman, W. ; Garcés, M. ; Langereis, C.G. ; Daams, R. ; Van Dam, J. ; Van Der Meulen, A.J. ; Agustí, J. ; Cabrera, L. ( 1996 ). `` A new chronology for the middle to late Miocene continental record in Spain ''. Earth and Planetary Science Letters. 142 ( 3 - 4 ) : 367 -- 380. Bibcode : 1996E&PSL. 142... 367K. doi : 10.1016 / 0012 - 821X ( 96 ) 00109 - 4. Jump up ^ `` Neogene ''. Merriam - Webster Dictionary. Jump up ^ `` Neogene ''. Dictionary.com Unabridged. Random House. Jump up ^ https://phys.org/news/2017-05-scientists-million-year-old-pre-human-balkans.html Jump up ^ Tucker, M.E. ( 2001 ) Sedimentary Petrology ( 3rd ed. ) Blackwell Science, Osney Nead, Oxford, UK, ISBN 0 - 632 - 05735 - 1 Jump up ^ Lourens, L., Hilgen, F., Shackleton, N.J., Laskar, J., Wilson, D., ( 2004 ) `` The Neogene Period ''. In : Gradstein, F., Ogg, J., Smith, A.G. ( Eds. ), Geologic Time Scale Cambridge University Press, Cambridge. Jump up ^ Clague, John et al. ( 2006 ) `` Open Letter by INQUA Executive Committee '' Quaternary Perspective, the INQUA Newsletter International Union for Quaternary Research 16 ( 1 ) Jump up ^ ICS : Consolidated Annual Report for 2006, last retrieved on 15 June 2007 Jump up ^ International Geological Congress, General Proceedings for 33rd congress, Oslo, August 6 -- 14, 2008 ( 1 ) Jump up ^ See the 2009 version of the ICS geologic time scale External links Wikimedia Commons has media related to Neogene. Wikisource has original works on the topic : Cenozoic # Neogene Digital Atlas of Neogene Life for the Southeastern United States -- by San Jose State University via Web Archive. Neogene Period Miocene Pliocene Aquitanian Burdigalian Langhian Serravallian Tortonian Messinian Zanclean Piacenzian Preceded by Proterozoic Eon Phanerozoic Eon Paleozoic Era Mesozoic Era Cenozoic Era Cambrian Ordovician Silurian Devonian Carboniferous Permian Triassic Jurassic Cretaceous Paleogene Neogene 4ry Geologic history of Earth Cenozoic era ( present -- 66.0 Mya ) Quaternary ( present -- 2.588 Mya ) Holocene ( present -- 11.784 kya ) Pleistocene ( 11.784 kya -- 2.588 Mya ) Neogene ( 2.588 -- 23.03 Mya ) Pliocene ( 2.588 -- 5.333 Mya ) Miocene ( 5.333 -- 23.03 Mya ) Paleogene ( 23.03 -- 66.0 Mya ) Oligocene ( 23.03 -- 33.9 Mya ) Eocene ( 33.9 -- 56.0 Mya ) Paleocene ( 56.0 -- 66.0 Mya ) Mesozoic era ( 66.0 -- 252.17 Mya ) Cretaceous ( 66.0 -- 145.0 Mya ) Late ( 66.0 -- 100.5 Mya ) Early ( 100.5 -- 145.0 Mya ) Jurassic ( 145.0 -- 201.3 Mya ) Late ( 145.0 -- 163.5 Mya ) Middle ( 163.5 -- 174.1 Mya ) Early ( 174.1 -- 201.3 Mya ) Triassic ( 201.3 -- 252.17 Mya ) Late ( 201.3 -- 237 Mya ) Middle ( 237 -- 247.2 Mya ) Early ( 247.2 -- 252.17 Mya ) Paleozoic era ( 252.17 -- 541.0 Mya ) Permian ( 252.17 -- 298.9 Mya ) Lopingian ( 252.17 -- 259.8 Mya ) Guadalupian ( 259.8 -- 272.3 Mya ) Cisuralian ( 272.3 -- 298.9 Mya ) Carboniferous ( 298.9 -- 358.9 Mya ) Pennsylvanian ( 298.9 -- 323.2 Mya ) Mississippian ( 323.2 -- 358.9 Mya ) Devonian ( 358.9 -- 419.2 Mya ) Late ( 358.9 -- 382.7 Mya ) Middle ( 382.7 -- 393.3 Mya ) Early ( 393.3 -- 419.2 Mya ) Silurian ( 419.2 -- 443.8 Mya ) Pridoli ( 419.2 -- 423.0 Mya ) Ludlow ( 423.0 -- 427.4 Mya ) Wenlock ( 427.4 -- 433.4 Mya ) Llandovery ( 433.4 -- 443.8 Mya ) Ordovician ( 443.8 -- 485.4 Mya ) Late ( 443.8 -- 458.4 Mya ) Middle ( 458.4 -- 470.0 Mya ) Early ( 470.0 -- 485.4 Mya ) Cambrian ( 485.4 -- 541.0 Mya ) Furongian ( 485.4 -- 497 Mya ) Series 3 ( 497 -- 509 Mya ) Series 2 ( 509 -- 521 Mya ) Terreneuvian ( 521 -- 541.0 Mya ) Proterozoic eon ( 541.0 Mya -- 2.5 Gya ) Neoproterozoic ( 541.0 Mya -- 1 Gya ) Ediacaran ( 541.0 - ~ 635 Mya ) Cryogenian ( ~ 635 - ~ 720 Mya ) Tonian ( ~ 720 Mya - 1 Gya ) Mesoproterozoic ( 1 -- 1.6 Gya ) Stenian ( 1 - 1.2 Gya ) Ectasian ( 1.2 - 1.4 Gya ) Calymmian ( 1.4 - 1.6 Gya ) Paleoproterozoic ( 1.6 -- 2.5 Gya ) Statherian ( 1.6 - 1.8 Gya ) Orosirian ( 1.8 - 2.05 Gya ) Rhyacian ( 2.05 - 2.3 Gya ) Siderian ( 2.3 - 2.5 Gya ) Archean eon ( 2.5 -- 4 Gya ) Eras Neoarchean ( 2.5 -- 2.8 Gya ) Mesoarchean ( 2.8 -- 3.2 Gya ) Paleoarchean ( 3.2 -- 3.6 Gya ) Eoarchean ( 3.6 -- 4 Gya ) Hadean eon ( 4 -- 4.6 Gya ) ( Informal ) kya = thousands years ago. Mya = millions years ago. Gya = billions years ago. Source : ( 2015 / 01 ). International Commission on Stratigraphy. Retrieved 13 July 2015. Divisions of Geologic Time -- Major Chronostratigraphic and Geochronologic Units USGS Retrieved 10 March 2013. GND : 4130779 - 3 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Neogene&oldid=792778312 '' Categories : Neogene Cenozoic Cenozoic geochronology Geological periods Hidden categories : Periods with timeline in infobox Wikipedia articles with GND identifiers Talk Contents About Wikipedia Afrikaans Alemannisch Asturianu Bahasa Banjar Bân - lâm - gú Беларуская Беларуская ( тарашкевіца ) ‎ Български Brezhoneg Català Čeština Cymraeg Dansk Deutsch Eesti Ελληνικά Español Esperanto Euskara فارسی Français Galego 한국어 Հայերեն Bahasa Indonesia Íslenska Italiano עברית ქართული Қазақша Кыргызча Latina Latviešu Lëtzebuergesch Lietuvių Magyar Bahasa Melayu Nederlands 日本 語 Norsk Norsk nynorsk Occitan Oʻzbekcha / ўзбекча پنجابی Plattdüütsch Polski Português Română Русский Саха тыла Scots Simple English Slovenčina Slovenščina Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska Tagalog ไทย Türkçe Українська Tiếng Việt Yorùbá 粵語 中文 Edit links This page was last edited on 28 July 2017, at 16 : 28. 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Question: the uppermost epoch of the neogene period is
Answer: Pliocene