The freediving champions of the dolphin world

For the first time, researchers have explored the physiological adaptations that enable different populations of the same species of dolphin to vary in diving ability by almost 1000m. The research, published in two complementary studies in Frontiers in Physiology, compared the lung mechanics and metabolic rates of bottlenose dolphin populations known for their different hunting depths. Using theoretical estimates of gas management, the results support a new hypothesis that lung architecture and the management of blood flow allow the dolphins to access oxygen in the lungs while preventing uptake of nitrogen, thereby avoiding decompression sickness.