Green Iguana (IMAGE) University of Utah Caption University of Utah scientists have shown that the green iguana uses bird-like breathing, bolstering the case that the specialization evolved in a common ancestor of lizards, snakes, crocodiles and dinosaurs including birds. Credit Bob Cieri Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.