About 15 years ago, during a fishing expedition off the west coast of Greenland, Danish marine biologist John Steffensen spotted a local hunter in a small boat. A large, voluminous dull-gray shark hung from the boat’s edge. “I kind of went,‘Wow, I’ve never seen a Greenland shark before,’” says Steffensen, who then told the captain of his own ship that he’d love to catch one someday. “And the captain on our boat, he was laughing at me.” Why, the captain must have been wondering, would anyone want to catch a…
