Heart Monitor-Wearing Narwhals Reveal the Dangers of Human Encounters - National Geographic

National Geographic

Heart Monitor-Wearing Narwhals Reveal the Dangers of Human Encounters National Geographic Scientists measure the length of an adult narwhal for a study of the animals' response to danger. Narwhals' heart rates plummet to a few beats per minute while they dive deep to escape fishing nets. Photograph by M.P. Heide-Jorgensen. By Jason Bittel ... and more »