[00:01.75]The same signs appear in young male mammoth tusks, 
在年轻雄性猛犸象的象牙上也显示了同样的信息，
[00:06.56]but those living in North America at the end of Ice Age laid down their stress rings three years earlier than usual. 
但是在冰河时代末期，那些生活在北美的猛犸象却提前三年开始自谋生路。
[00:13.59]In other words, it seems that young males were leaving the herd at an earlier age. 
换言之，似乎那些年轻的雄性猛犸象很早就离开了族群。
[00:21.18]Some scientists believe the only thing that could cause such a major change in mammoth’s social structure would be hunting by humans. 
一些科学家认为，唯一导致猛犸象社会结构主要变化的原因就是人类的捕杀。
[00:29.97]If hunting pressure was extreme enough to push the mammoths to extinction, 
如果猎杀的程度已经导致它们灭亡，
[00:33.61]then we would expect them to survive in areas that people couldn’t reach. 
那么它们也只有在人类触及不到的地区才能存活。
[00:41.04]And for a while, they did, here on Wrangel Island off the coast of Siberia. 
事实上的却如此，在西伯利亚海岸的弗兰格尔岛上，它们的确幸存了。
[00:46.35]There are no mammoths on Wrangel Island today, but it is home to another large animal, the polar bear. 
如今，弗兰格尔岛上已经没有猛犸象了，但是这里却又另一种大型动物——北极熊。
[01:00.17]And there is evidence that polar bears and mammoths once lived side by side during the last Ice Age. 
有证据显示在冰河时代末期，猛犸象曾和北极熊共同定居于此。
[01:10.20]They would have shared the island’s meager offerings. 
他们共同分享着这个贫瘠之地能给予它们的一切。
[01:20.11]This inhospitable and isolated place seems to have been a sanctuary for mammoths. 
这个荒凉并与世隔绝的地方似乎对于猛犸系来说是一个天然的庇护所。
[01:29.56]The Wrangel Island herds were the last on the planet to survive. 
迁徙到弗兰格尔岛的猛犸象是地球上最后一支猛犸象族群了。
[01:38.28]Remarkably, they survived here long after their North American relatives had all died out. 
很明显，他们在这里得以幸存，而它们的其他族群都已灭绝。
[01:45.18]But they were still on borrowed time. When people finally reached Wrangel Island 4,000 years ago, 
然而，它们也只不过是延长了死亡的时间而已。当4000年前，人类最终找到弗兰格尔岛后，
[01:52.15]these last remaining mammoths also became extinct. 
这里的最后一支猛犸象族群也灭绝了。
[02:00.61]The events on Wrangel Island mirrored what had happened on the North American continent. 
弗兰格尔岛的这个事件反映了北美大陆的状况。
[02:10.45]Mammoths only became extinct after they came into contact with people.
在与人类接触后，猛犸象便会灭绝。