Editing Miocene (section)

===Flora===
[[File:Socotra dragon tree.JPG|thumbnail|The [[Dracaena cinnabari|dragon blood tree]] is considered a remnant of the Mio-Pliocene Laurasian subtropical forests that are now almost extinct in North Africa.<ref>{{Cite journal| doi = 10.1016/j.biocon.2007.05.009| title = Will dragonblood survive the next period of climate change? Current and future potential distribution of Dracaena cinnabari (Socotra, Yemen)| year = 2007| last1 = Attorre | first1 = F.| last2 = Francesconi | first2 = F.| last3 = Taleb | first3 = N.| last4 = Scholte | first4 = P.| last5 = Saed | first5 = A.| last6 = Alfo | first6 = M.| last7 = Bruno | first7 = F.| journal = [[Biological Conservation (journal)|Biological Conservation]]| volume = 138| issue = 3–4| pages = 430–439| bibcode = 2007BCons.138..430A| hdl = 11573/234206}}</ref>]]

The [[coevolution]] of [[phytolith|gritty]], fibrous, fire-tolerant [[Poaceae|grasses]] and long-legged [[herd behavior|gregarious]] [[ungulate]]s with [[hypsodont|high-crowned teeth]], led to a major expansion of grass-grazer [[ecosystems]]{{citation needed|date=January 2024}}. Herds of large, [[cursorial|swift]] [[Grazing|grazers]] were hunted by [[Predation|predators]] across broad sweeps of open [[grassland]]s, displacing desert, woodland, and browsers{{citation needed|date=January 2024}}.

The higher organic content and water retention of the deeper and richer [[Mollisol|grassland soils]], with long-term [[Carbon sequestration|burial of carbon]] in sediments, produced a [[Greenhouse gas|carbon and water vapor]] sink. This, combined with higher surface albedo and lower [[evapotranspiration]] of grassland, contributed to a cooler, drier climate.<ref>{{cite journal
 |last        = Retallack
 |first       = Gregory
 |title       = Cenozoic Expansion of Grasslands and Climatic Cooling
 |year        = 2001
 |journal     = [[The Journal of Geology]]
 |volume      = 109
 |issue       = 4
 |pages       = 407–426
 |publisher   = University of Chicago Press
 |url         = http://pages.uoregon.edu/dogsci/_media/directory/faculty/greg/grasslandscooling.pdf?id=directory%3Afaculty%3Agreg%3Aabout&cache=cache
 |bibcode     = 2001JG....109..407R
 |doi         = 10.1086/320791
 |s2cid = 15560105
 |archive-url  = https://web.archive.org/web/20130506232759/http://pages.uoregon.edu/dogsci/_media/directory/faculty/greg/grasslandscooling.pdf?id=directory%3Afaculty%3Agreg%3Aabout&cache=cache
 |archive-date = 2013-05-06
}}</ref> [[C4 carbon fixation#The evolution and advantages of the C4 pathway|C<sub>4</sub>]] grasses, which are able to assimilate [[carbon dioxide]] and water more efficiently than [[C3 carbon fixation|C<sub>3</sub>]] grasses, expanded to become ecologically significant near the end of the Miocene between 6 and 7 million years ago,<ref name="Osborne2006">{{cite journal |author=Osborne, C.P. |author2=Beerling, D.J. |author-link2=David Beerling |year=2006 |title=Nature's green revolution: the remarkable evolutionary rise of C4 plants |journal=[[Philosophical Transactions of the Royal Society B: Biological Sciences]] |volume=361 |issue=1465 |pages=173–194 |doi=10.1098/rstb.2005.1737 |pmc=1626541 |pmid=16553316}}</ref> although they did not expand northward during the Late Miocene.<ref>{{Cite journal |last1=Fraser |first1=Danielle |last2=Theodor |first2=Jessica M. |date=1 January 2013 |title=Ungulate diets reveal patterns of grassland evolution in North America |url=https://www.sciencedirect.com/science/article/pii/S0031018212006311 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |language=en |volume=369 |pages=409–421 |doi=10.1016/j.palaeo.2012.11.006 |access-date=1 November 2024 |via=Elsevier Science Direct}}</ref> The expansion of grasslands and [[Evolutionary radiation|radiations]] among terrestrial herbivores correlates to fluctuations in CO<sub>2</sub>.<ref>{{cite journal |author=Wolfram M. Kürschner, Zlatko Kvacek & David L. Dilcher |title=The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of terrestrial ecosystems |year=2008 |journal=[[Proceedings of the National Academy of Sciences of the United States of America]] |volume=105 |issue=2 |pages=449–53 |doi=10.1073/pnas.0708588105 |bibcode = 2008PNAS..105..449K |pmid=18174330 |pmc=2206556|doi-access=free }}</ref> One study, however, has attributed the expansion of grasslands not to a CO<sub>2</sub> drop but to the increasing seasonality and aridity, coupled with a monsoon climate, which made wildfires highly prevalent compared to before.<ref>{{cite journal |last1=Keeley |first1=Jon E. |last2=Rundel |first2=Philip W. |date=28 April 2005 |title=Fire and the Miocene expansion of C4 grasslands |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1461-0248.2005.00767.x |journal=[[Ecology Letters]] |volume=8 |issue=7 |pages=683–690 |doi=10.1111/j.1461-0248.2005.00767.x |bibcode=2005EcolL...8..683K |access-date=21 March 2023}}</ref> The Late Miocene expansion of grasslands had cascading effects on the global carbon cycle, evidenced by the imprint it left in carbon isotope records.<ref>{{Cite journal |last1=Du |first1=Jinlong |last2=Tian |first2=Jun |last3=Ma |first3=Wentao |date=15 April 2022 |title=The Late Miocene Carbon Isotope Shift driven by synergetic terrestrial processes: A box-model study |url=https://www.sciencedirect.com/science/article/pii/S0012821X22000930 |journal=[[Earth and Planetary Science Letters]] |volume=584 |pages=117457 |doi=10.1016/j.epsl.2022.117457 |bibcode=2022E&PSL.58417457D |s2cid=247307062 |issn=0012-821X |access-date=30 December 2023 |via=Elsevier Science Direct}}</ref>

[[Cycad]]s between 11.5 and 5 million years ago began to rediversify after previous declines in variety due to climatic changes, and thus modern cycads are not a good model for a "living fossil".<ref>{{cite journal |author=Susanne S. Renner |title=Living fossil younger than thought |year=2011 |journal=[[Science (journal)|Science]] |volume=334 |issue=6057 |pages=766–767 |doi=10.1126/science.1214649 |pmid=22076366|bibcode = 2011Sci...334..766R|s2cid=206537832 }}</ref> [[Eucalyptus]] fossil leaves occur in the Miocene of [[New Zealand]], where the genus is not native today, but have been introduced from [[Australia]].<ref>{{cite web|url=https://mikepole.wordpress.com/2014/09/22/eucalyptus-fossils-in-new-zealand-the-thin-end-of-the-wedge/|title=Eucalyptus fossils in New Zealand - the thin end of the wedge - Mike Pole|date=2014-09-22}}</ref>