Editing Lizard (section)

===Respiration===
Recent studies (2013 and 2014) on the lung anatomy of the [[savannah monitor]] and [[green iguana]] found them to have a unidirectional airflow system, which involves the air moving in a loop through the lungs when breathing. This was previously thought to only exist in the [[archosaurs]] ([[crocodilian]]s and [[bird]]s). This may be evidence that unidirectional airflow is an ancestral trait in [[diapsid]]s.<ref>{{cite journal |author1=Schachner, Emma R. |author2=Cieri, Robert L. |author3=Butler, James P. |author4=Farmer, C. G. |year=2014 |title=Unidirectional pulmonary airflow patterns in the savannah monitor lizard |journal=Nature |volume=506 |issue=7488 |pages=367–370 |doi=10.1038/nature12871|pmid=24336209 |bibcode=2014Natur.506..367S |s2cid=4456381 |url=http://nrs.harvard.edu/urn-3:HUL.InstRepos:32631102 |url-access=subscription }}</ref><ref>{{cite journal |author1=Robert L. |author2=Craven, Brent A. |author3=Schachner, Emma R. |author4=Farmer, C. G. |year=2014 |title=New insight into the evolution of the vertebrate respiratory system and the discovery of unidirectional airflow in iguana lungs |journal=PNAS |volume=111 |issue=48 |pages=17218–17223 |doi=10.1073/pnas.1405088111|pmid=25404314 |pmc=4260542 |bibcode=2014PNAS..11117218C |doi-access=free }}</ref>