Now having evolved language, though, we did something peculiar, even bizarre. 尽管我们有发达的语言，但我们也做了件特殊，甚至可以说是件奇怪的事

　　As we spread out around the world, we developed thousands of different languages. 当我们分散到全世界，我们发展出成千上万种语言

　　Currently, there are about seven or 8,000 different languages spoken on Earth. 目前，全球大约有七千到八千种在使用的语言

　　Now you might say, well, this is just natural. 也许你觉得这是很自然的事

　　As we diverge, our languages are naturally going to diverge. 当我们越分散，语言也越高度分化

　　But the real puzzle and irony is that the greatest density of different languages on Earth 但真正令人困惑并且讽刺的是，世界上最密集的语言分布区域

　　is found where people are most tightly packed together. 恰恰是人口最密集聚居的地方

　　If we go to the island of Papua New Guinea, 在巴布新几内亚

　　we can find about 800 to 1,000 distinct human languages, 那里有八百到一千种独特的人类语言

　　different human languages, spoken on that island alone. 不同的人类语言，仅仅在那一座岛上

　　There are places on that island where you can encounter a new language every two or three miles. 岛上一些地方，你每走上两三英里就能碰上一种新语言

　　Now, incredible as this sounds, I once met a Papuan man, and I asked him if this could possibly be true. 更神奇的是，有次我碰上一个巴布人，问他这是不是真的

　　And he said to me, "Oh no. They're far closer together than that." 他说：“不，不是。比这要近多了。”

　　And it's true; there are places on that island where you can encounter a new language in under a mile. 这是真的，岛上有些地方，一英里之内就能发现另一语言的使用

　　And this is also true of some remote oceanic islands. 同样在一些遥远的大洋小岛上也是这样

　　And so it seems that we use our language, not just to cooperate, 这样看来我们利用语言不仅仅是为了合作

　　but to draw rings around our cooperative groups and to establish identities, 也是在集团周围划分界限确立身份

　　and perhaps to protect our knowledge and wisdom and skills from eavesdropping from outside. 也许是保护我们的知识，智慧和技能，以防落入外人之手

　　And we know this because when we study different language groups and associate them with their cultures, 我们也深知如此，因为当我们研究不同的语言群落，他们有着各自的文化

　　we see that different languages slow the flow of ideas between groups. 会发现不同的语言，减缓了群落间想法的交流

　　They slow the flow of technologies. And they even slow the flow of genes. 也阻碍了技术交流，甚至是基因交流