Stalk the Arctic ice with the fiercest predator, the polar bear, as it prowls one of the most forbidding places on the planet: a hidden kingdom of magnificent creatures. Armed with a keen sense of smell and backed up by 1,700 pounds, fur an...
世界极地,只有强者能生存。 美国国家地理学会邀请您到北极冰原、一处蕴涵神奇生物的王国,和世界最残忍的掠食者-北极熊一起漫步,看它在地表最艰险的地域徘徊觅食。因...