Discover how cetaceans like dolphins and whales masterfully regulate their body temperature in water, 25 times more conductive than air. Their secret lies in a remarkable subcutaneous blubber layer, adapting to cold and warmth like a cozy jacket. Chinese researchers used ultrasound to unveil changing blubber thickness in Yangtze finless porpoises as water temperature shifts, shedding light on appetite's role. This intricate interplay between energy intake, blubber, and temperature beckons further exploration, offering insights into cetaceans' adaptive prowess and potential conservation strategies. Explore the science in Water Biology and Security.