Young polar bear cubs((곰·사자·이리 등) 짐승 새끼, 어린 짐승), freshly out of the den(굴, 동굴) peek out(훔쳐보다, 엿보다) from behind their mother as she rests on the sea ice(해빙) near Ellesmere Island, Nunavut(누나부트(캐나다 북부의 에스키모족 자치구로 준주(準州); 1999년 설치)). Polar bears are masters at conserving energy(에너지 보존하기의 명수). At this stage, these cubs are drinking milk that has 33% fat content compared to humans at 3-5%(지방 함량이 33%인..