Iguanas’ one-way airflow undermines usual view of lung evolution
Not just active birds but sedentary lizards with simple lungs have unusual breathing dynamics
![iguana](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2014/11/sm_iguana_feat_free.jpg?fit=860%2C460&ssl=1)
FANCY BREATH A green iguana’s lungs manage sophisticated one-way air flow with deceptively simple structures.
Christian Mehlführer/Wikimedia Commons (CC BY 2.5)