As anyone who has ever blown bubbles as or with a child knows, if you stop blowing before the sphere is complete, it collapses and disappears. The gas exchange surfaces of our lungs, the alveoli, are also highly curved, thin-walled, moist membranes that are open to the atmosphere. They too, would tend to go poof! and disappear, save for a mixture of phospholipids and proteins that lines the epithelial surfaces of vertebrate lungs, called surfactant. In the alveoli, surfactant’s primary function is to decrease surface tension to ensure that the ‘bubbles’ remain open during successive cycles of respiratory contraction and expansion. Both neonatal and adult respiratory distress syndromes result from a lack of surfactant, leading to increased surface tension, decreased lung compliance, and lung collapse. Animalderived surfactants have been used to treat respiratory distress syndrome in infants since the early 1990s with great success, and an increased understanding of its components, especially surfactant associated proteins, has led to the development of newer synthetic versions. Recent evidence indicates, however, that not all surfactants are created equal. Composition and function differ between vertebrate groups as well as developmentally, depending on pulmonary anatomy and respiratory physiology. These differences interested a group led by Dr Roger Spragg at UC San Diego School of Medicine, who wondered if diving animals, that have evolved to suffer repeatedly lung collapse and re-expansion, would have developed unique surfactants to facilitate such cycles.