Editing Smile (section)

== Evolutionary background ==
Primatologist Signe Preuschoft traces the smile back over 30 million years of evolution to a "fear grin" stemming from monkeys and apes, who often used barely clenched teeth to portray to predators that they were harmless<ref>{{Cite journal |url=https://academic.oup.com/scan/article/1/3/221/2362993 |access-date=2022-05-07 |journal=Social Cognitive and Affective Neuroscience | year=2006 |doi=10.1093/scan/nsl031 |pmc=2555422 |pmid=18985109| last1=Parr | first1=L. A. | last2=Waller | first2=B. M. | title=Understanding chimpanzee facial expression: Insights into the evolution of communication | volume=1 | issue=3 | pages=221–228 }}</ref> or to signal submission to more dominant group members. The smile may have evolved differently among species, especially among humans.<ref>{{cite web|url=https://gizmodo.com/why-do-we-smile-and-laugh-when-were-terrified-1441046376|title=Why do we smile and laugh when we're terrified?|last=Inglis-Arkell|first=Esther|date=7 October 2013|website=Gizmodo|access-date=7 October 2016}}</ref>