Guardian: Polar bears may get more attention – and later this week a court-ordered decision by the US government will almost certainly see them listed as a threatened species – but new research suggests the narwhal, the mysterious whale with a long spiral tusk, may be more at risk from climatic change. Researchers fear that the narwhal is so attuned to its environment, so narrow in its range of habitat and specific in diet, that it may be one of the least able of Arctic mammals to adapt to rapid …