Editing Pleistocene (section)

==Etymology==
[[Charles Lyell]] introduced the term "Pleistocene" in 1839 to describe strata in [[Sicily]] that had at least 70% of their molluscan fauna still living today. This distinguished it from the older [[Pliocene|Pliocene Epoch]], which Lyell had originally thought to be the youngest fossil rock layer. He constructed the name "Pleistocene" ('most new' or 'newest') from the [[Greek language|Greek]] ''πλεῖστος'' (''pleīstos'') 'most' and ''καινός'' (''kainós'' ([[Latin]]ized as ''cænus'') 'new').<ref>{{cite book |last1=Lyell |first1=Charles |title=Nouveaux éléments de géologie |date=1839 |publisher=Pitois-Levranet |location=Paris, France |page=621 |url=https://archive.org/stream/elmentsdegologi00meulgoog#page/n657/mode/2up |language=fr}} From p. 621:  ''"Toutefois, en même temps … et de substituer à la dénomination de Nouveau Pliocène celle plus abrégée de ''Pleistocène'', tirée du grec pleiston, ''plus'', et kainos, ''récent''."'' (However, at the same time that it became necessary to subdivide the two periods mentioned above, I found that the terms intended to designate these subdivisions were of an inconvenient length, and I have proposed to use in the future the word "Pliocene" for "old Pliocene", and to substitute for the name "new Pliocene" this shorter "Pleistocene", drawn from the Greek ''pleiston'' (most) and ''kainos'' (recent).)</ref><ref>{{cite book |last1=Wilmarth |first1=Mary Grace |title=Bulletin 769: The Geologic Time Classification of the United States Geological Survey Compared With Other Classifications, accompanied by the original definitions of era, period and epoch terms |date=1925 |publisher=U.S. Government Printing Office |location=Washington, D.C., U.S. |page=47 |url=https://books.google.com/books?id=my7x_PBkpm4C&pg=PA47}}</ref><ref name=OnlineEtDict>{{cite dictionary|title=Pleistocene|url=http://www.etymonline.com/index.php?term=Pleistocene&allowed_in_frame=0|dictionary=[[Online Etymology Dictionary]]}}</ref> This contrasts with the immediately preceding [[Pliocene]] ("newer", from ''πλείων'' (''pleíōn'', "more") and ''kainós'') and the immediately subsequent [[Holocene]] ("wholly new" or "entirely new", from ''ὅλος'' (''hólos'', "whole") and ''kainós'') [[Geologic time scale|epoch]], which extends to the present time.