information:classification, stylistic:tone
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 (crocodilians and birds). This may be evidence that unidirectional airflow is an ancestral trait in diapsids.