In a moment that stunned the world, marine biologist Nan Hauser found herself in the middle of an extraordinary rescue — by a humpback whale. While diving off the Cook Islands, Hauser suddenly felt a 40-ton whale pressing against her, nudging, even tucking her beneath its massive fin. Confused, she tried to move away — until she saw what the whale had seen first: a tiger shark, circling nearby. For over seven minutes, the whale shielded her — lifting her above the surface, blocking the shark wit