How Some Mammals Nearly Stop Their Hearts to Stay Alive

A healthy human heart beats around 60 to 100 times every minute, constantly pumping blood to keep the body alive. Stopping or dramatically slowing the heartbeat would usually be life-threatening. Yet in the natural world, some mammals do exactly that as a remarkable survival strategy. During hibernation or deep dives, these animals can reduce their heart rate to just a handful of beats per minute, conserving precious energy and oxygen when resources are limited. This extraordinary adaptation has fascinated scientists for decades, offering valuable insights into biology, medicine and even the future of long-duration space travel.