Editing Stoma (section)

==Evolution==
[[File:Tomato stoma observed through immersion oil.gif|thumb|Tomato stoma observed through immersion oil]]
There is little evidence of the evolution of stomata in the fossil record, but they had appeared in land plants by the middle of the Silurian period.<ref>{{Cite journal
 | last1 = D. Edwards | first1 = H. Kerp
 | last2 = Hass | first2 = H.
 | year = 1998
 | title = Stomata in early land plants: an anatomical and ecophysiological approach
 | journal = Journal of Experimental Botany
 | volume = 49
 | pages = 255–278
 | doi = 10.1093/jxb/49.Special_Issue.255
 | issue = Special Issue
| doi-access = free
 }}</ref> They may have evolved by the modification of [[conceptacles]] from plants' alga-like ancestors.<ref>{{cite book
 | last = Krassilov | first = Valentin A.
 | chapter = Macroevolutionary events and the origin of higher taxa
 | pages=265–289
 | chapter-url=https://books.google.com/books?id=tJeZC885-OcC&pg=PA265
 | isbn = 978-1-4020-1693-6
 | editor-first = Solomon P.
 | editor-last= Wasser
 | year = 2004
 | publisher = Kluwer Acad. Publ.
 | location = Dordrecht
 | title = Evolutionary theory and processes : modern horizons : papers in honour of Eviatar Nevo }}</ref>
However, the evolution of stomata must have happened at the same time as the waxy [[Plant cuticle|cuticle]] was evolving&nbsp;– these two traits together constituted a major advantage for early terrestrial plants.{{citation needed|date=May 2017}}