Editing Dinosaur (section)

===Behavioral evidence===
Fossils of the troodonts ''[[Mei long|Mei]]'' and ''[[Sinornithoides]]'' demonstrate that some dinosaurs slept with their heads tucked under their arms.<ref name=XUNorell2004/> This behavior, which may have helped to keep the head warm, is also characteristic of modern birds. Several [[Deinonychosauria|deinonychosaur]] and oviraptorosaur specimens have also been found preserved on top of their nests, likely brooding in a bird-like manner.<ref name="norell1995">{{cite journal |last1=Norell |first1=Mark A. |last2=Clark |first2=James M. |last3=Chiappe |first3=Luis M. |last4=Dashzeveg |first4=Demberelyin |display-authors=3 |year=1995 |title=A nesting dinosaur |journal=Nature |location=London |publisher=Nature Research |volume=378 |issue=6559 |pages=774–776 |bibcode=1995Natur.378..774N |doi=10.1038/378774a0 |s2cid=4245228 |issn=0028-0836}}</ref> The ratio between egg volume and body mass of adults among these dinosaurs suggest that the eggs were primarily brooded by the male and that the young were highly precocial, similar to many modern ground-dwelling birds.<ref name=Varricchioetal2008>{{cite journal |last1=Varricchio |first1=David J. |last2=Moore |first2=Jason R. |last3=Erickson |first3=Gregory M. |author3-link=Gregory M. Erickson |last4=Norell |first4=Mark A. |last5=Jackson |first5=Frankie D. |last6=Borkowski |first6=John J. |display-authors=3 |year=2008 |title=Avian Paternal Care Had Dinosaur Origin |journal=Science |location=Washington, D.C. |publisher=American Association for the Advancement of Science |volume=322 |issue=5909 |pages=1826–1828 |bibcode=2008Sci...322.1826V |doi=10.1126/science.1163245 |issn=0036-8075 |pmid=19095938|s2cid=8718747 |doi-access=free }}</ref>

Some dinosaurs are known to have used [[gizzard]] stones like modern birds. These stones are swallowed by animals to aid digestion and break down food and hard fibers once they enter the stomach. When found in association with fossils, gizzard stones are called gastroliths.<ref name=wings2007/>