@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev “The respiratory organs of vertebrates exhibit a tremendous degree of diversity, but the lung-air sac system of birds is truly unique among extant species,” says Dr. Markus Lambertz from the Institute for Zoology at the University of Bonn in Germany. Air sacs are bellows-like protrusions of the lung, […]