Editing Jurassic (section)

==== Cycads ====
[[Cycad]]s reached their apex of diversity during the Jurassic and Cretaceous Periods.<ref name="Cai-2018">{{Cite journal |last1=Cai |first1=Chenyang |last2=Escalona |first2=Hermes E. |last3=Li |first3=Liqin |last4=Yin |first4=Ziwei |last5=Huang |first5=Diying |last6=Engel |first6=Michael S. |date=September 2018 |title=Beetle Pollination of Cycads in the Mesozoic |journal=Current Biology |language=en |volume=28 |issue=17 |pages=2806–2812.e1 |doi=10.1016/j.cub.2018.06.036 |pmid=30122529|s2cid=52038878|doi-access=free |bibcode=2018CBio...28E2806C }}</ref> Despite the Mesozoic sometimes being called the "Age of Cycads", cycads are thought to have been a relatively minor component of mid-Mesozoic floras, with the Bennettitales and [[Nilssoniales]], which have cycad-like foliage, being dominant.<ref name="Coiro-2017">{{Cite journal |last1=Coiro |first1=Mario |last2=Pott |first2=Christian |date=December 2017|title=Eobowenia gen. nov. from the Early Cretaceous of Patagonia: indication for an early divergence of Bowenia? |journal=BMC Evolutionary Biology |language=en |volume=17 |issue=1 |pages=97 |doi=10.1186/s12862-017-0943-x|issn=1471-2148 |pmc=5383990 |pmid=28388891 |doi-access=free |bibcode=2017BMCEE..17...97C }}</ref> The Nilssoniales have often been considered cycads or cycad relatives, but have been found to be distinct on chemical grounds, and perhaps more closely allied with Bennettitales.''<ref name="Vajda-2017">{{Cite journal |last1=Vajda |first1=Vivi |last2=Pucetaite |first2=Milda |last3=McLoughlin |first3=Stephen |last4=Engdahl |first4=Anders |last5=Heimdal |first5=Jimmy |last6=Uvdal |first6=Per |date=August 2017 |title=Molecular signatures of fossil leaves provide unexpected new evidence for extinct plant relationships |url=https://www.nature.com/articles/s41559-017-0224-5 |journal=Nature Ecology & Evolution |language=en |volume=1 |issue=8 |pages=1093–1099 |doi=10.1038/s41559-017-0224-5 |issn=2397-334X |pmid=29046567 |bibcode=2017NatEE...1.1093V |s2cid=3604369}}</ref>'' The relationships of most Mesozoic cycads to living groups are ambiguous,<ref name="Coiro-2017" /> with no Jurassic cycads belonging to either of the two modern groups of cycads, though some Jurassic cycads possibly represent [[stem-group]] relatives of modern [[Cycadaceae]], like the leaf genus ''[[Paracycas]]'' known Europe, and [[Zamiaceae]], like some European species of the leaf genus ''[[Pseudoctenis]]''. Also widespread during the Jurassic was the extinct ''[[Ctenis]]'' lineage, which appears to be distantly related to modern cycads.<ref>{{Cite journal |last1=Coiro |first1=Mario |last2=Allio |first2=Rémi |last3=Mazet |first3=Nathan |last4=Seyfullah |first4=Leyla J. |last5=Condamine |first5=Fabien L. |date=2023-06-11 |title=Reconciling fossils with phylogenies reveals the origin and macroevolutionary processes explaining the global cycad biodiversity |journal=New Phytologist |volume=240 |issue=4 |pages=1616–1635 |language=en |doi=10.1111/nph.19010 |pmid=37302411 |s2cid=259137975 |issn=0028-646X|doi-access=free |pmc=10953041 |bibcode=2023NewPh.240.1616C }}</ref> Modern cycads are pollinated by beetles, and such an association is thought to have formed by the Early Jurassic.<ref name="Cai-2018" />