The bends, formally called decompression sickness, occurs when scuba divers rise to the surface too quickly. During dives, divers breathe in compressed air containing nitrogen. This isn’t a problem at the bottom, and if divers rise slowly, the nitrogen is safely released through the lungs. If the process is rushed, nitrogen bubbles begin forming in the body, causing a case of “the bends.”
Symptoms include everything from confusion and odd behavior to paralysis and death. Dolphins have an intriguing adaptation to avoid these unpleasant side effects of deep dives. They can collapse their ribcage completely, forcing air pressure (and excess nitrogen) out of their lungs and funneling it into a series of complex air chambers below its blowhole.