People use the internet for various reasons.
人们因各种原因使用着互联网。
It turns out that one of the most popular categories of website is something that people typically consume in private.
一种最受欢迎的网站是人们常常私下浏览的东西。
It involves curiosity, non-insignificant levels of self-indulgence
它涉及到好奇心，无关自我放纵程度，
and is centered around recording the reproductive activities of other people.
并以记录他人的生殖记录为中心。
Of course, I'm talking about genealogy -- the study of family history.
当然，我讨论的是家谱学--也就是对家庭历史的研究。
When it comes to detailing family history, in every family, we have this person that is obsessed with genealogy.
当说到详细的家族历史，在每个家庭中，我们都有一个痴迷于家谱的人。
Let's call him Uncle Bernie.
我们姑且叫他伯尼叔叔吧。
Uncle Bernie is exactly the last person you want to sit next to in Thanksgiving dinner,
伯尼叔叔正是你在感恩节晚餐上，最不想坐在一起的人，
because he will bore you to death with peculiar details about some ancient relatives.
因为他会用一些远古亲戚的奇特细节把你烦死。
But as you know, there is a scientific side for everything,
但正如你所知，任何事物都有科学的一面，
and we found that Uncle Bernie's stories have immense potential for biomedical research.
我们发现伯尼叔叔的故事具有巨大的生物医学研究潜力。
We let Uncle Bernie and his fellow genealogists document their family trees through a genealogy website called geni.com.
我们让伯尼叔叔和他的家谱同行，通过族谱网站geni.com记录他们的家谱。
When users upload their trees to the website, it scans their relatives,
当用户上传他们的家谱树到网站时，网站会扫描他们的亲戚，
and if it finds matches to existing trees, it merges the existing and the new tree together.
如果它发现匹配上现存的家谱树，它会合并现存的和新的家谱树。
The result is that large family trees are created, beyond the individual level of each genealogist.
结果是超大的家族树创建起来了，超越了每个家谱学家的个人水平。
Now, by repeating this process with millions of people all over the world,
现在，凭借着全球数百万人不断重复这个过程，
we can crowdsource the construction of a family tree of all humankind.
我们可以众包全人类家谱树的建设。
Using this website, we were able to connect 125 million people into a single family tree.
使用这个网站，我们能够在一颗家族树上连接1.25亿人。
I cannot draw the tree on the screens over here because they have less pixels than the number of people in this tree.
我无法在这里的屏幕上画家谱树，因为它们的像素比在这棵树上的人还少。
But here is an example of a subset of 6,000 individuals. Each green node is a person.
但这里有一个6000人的子集例子。每一个绿色的节点是一个人。
The red nodes represent marriages, and the connections represent parenthood.
红色的节点代表婚姻，连接代表亲子关系。
In the middle of this tree, you see the ancestors.
在这个树的中央是祖先。
And as we go to the periphery, you see the descendants. This tree has seven generations, approximately.
外围是后代。这棵树大约有7代。
Now, this is what happens when we increase the number of individuals to 70,000 people
而这是当我们增加人数到7万人时的样子，
still a tiny subset of all the data that we have.
仍然是我们拥有的所有数据集的一小部分。
Despite that, you can already see the formation of gigantic family trees with many very distant relatives.
即便如此，你已经能够看到由许多远亲组成的一棵巨大家谱树。
Thanks to the hard work of our genealogists, we can go back in time hundreds of years ago.
感谢家谱学家的努力工作，我们可以回到数百年前。
For example, here is Alexander Hamilton, who was born in 1755.
比如，这是亚历山大·汉密尔顿，他出生于1755年。
Alexander was the first US Secretary of the Treasury, but mostly known today due to a popular Broadway musical.
亚历山大是首任美国财政部长，但主要由于一部流行的百老汇音乐剧而广为人知。
We found that Alexander has deeper connections in the showbiz industry.
我们发现亚历山大在娱乐圈有更深厚的人脉。
In fact, he's a blood relative of ... Kevin Bacon!
事实上，他是凯文·贝肯的血亲！
Both of them are descendants of a lady from Scotland who lived in the 13th century.
他们都是13世纪一位来自苏格兰的女士的后代。
So you can say that Alexander Hamilton is 35 degrees of Kevin Bacon genealogy.
所以你可以说亚历山大·汉密尔顿是35度凯文·贝肯的宗谱。
And our tree has millions of stories like that. We invested significant efforts to validate the quality of our data.
我们的家谱树有数百万类似的故事。我们投入了不小的工作在验证数据的质量上。
Using DNA, we found that .3 percent of the mother-child connections in our data are wrong,
使用DNA，我们发现我们数据中有0.3%的母子关系是错误的，
which could match the adoption rate in the US pre-Second World War.
这可能与二战前美国的收养率相当。
For the father's side, the news is not as good: 1.9 percent of the father-child connections in our data are wrong.
父亲方面，消息也并不乐观：我们的数据中1.9%的父子关系是错误的。
And I see some people smirk over here. It is what you think -- there are many milkmen out there.
我看到有人在这儿讪笑。这是你们在想的--外面有很多挤牛奶的人。
However, this 1.9 percent error rate in patrilineal connections is not unique to our data.
然而这1.9%的父子关系错误率不是我们数据独有的。
Previous studies found a similar error rate using clinical-grade pedigrees.
早先使用临床级血统的研究也发现了类似的错误率。
So the quality of our data is good, and that should not be a surprise.
所以我们的数据质量是良好的，并且这也不应该是个意外。
Our genealogists have a profound, vested interest in correctly documenting their family history.
我们的系谱学家对正确记录他们的家族史有着浓厚的兴趣。
We can leverage this data to learn quantitative information about humanity, for example, questions about demography.
我们可以利用这些数据来了解人类的定量信息，比如，有关人口统计学的问题。
Here is a look at all our profiles on the map of the world.
这是我们的资料在世界地图上的样子。
Each pixel is a person that lived at some point.
每个像素代表一个生活在特定位置的人。
And since we have so much data, you can see the contours of many countries, especially in the Western world.
由于我们有很多数据，你可以看到很多国家的轮廓，尤其在西方世界。
In this clip, we stratified the map that I've showed you based on the year of births of individuals from 1400 to 1900,
在这个视频片段中，我们把给你展示的地图根据1400-1900年出生的人口进行分层，
and we compared it to known migration events.
并且跟已知的迁移事件比较。
The clip is going to show you that the deepest lineages in our data go all the way back to the UK,
这个视频将向你展示我们数据中最深的血统，可以追溯到英国，
where they had better record keeping, and then they spread along the routes of Western colonialism. Let's watch this.
这里有更好的记录保存，然后他们沿着西方殖民主义的道路传播。让我们来看看这个。
I love this movie. Now, since these migration events are giving the context of families, we can ask questions such as:
我爱这个视频。因为这些移民时间提供了家庭的背景，我们可以问诸如此类的问题：
What is the typical distance between the birth locations of husbands and wives?
丈夫和妻子出生地的特定距离是多少？
This distance plays a pivotal role in demography,
这一距离在人口统计学中起着重要的作用，
because the patterns in which people migrate to form families determine how genes spread in geographical areas.
因为人们迁移形成家庭的模式决定了基因如何在地理位置上传播。

We analyzed this distance using our data, and we found that in the old days, people had it easy.
我们使用我们的数据分析了这个距离，我们发现在古时候，人们过得很轻松。
They just married someone in the village nearby. But the Industrial Revolution really complicated our love life.
他们只是跟村子附近的某人结婚。但工业革命复杂化了我们的爱情生活。
And today, with affordable flights and online social media,
今天，凭着可负担的航班和网络社交媒体，
people typically migrate more than 100 kilometers from their place of birth to find their soul mate.
人们通常从出生地迁移100多公里来寻找灵魂伴侣。
So now you might ask: OK, but who does the hard work of migrating from places to places to form families?
所以现在你可能会问：好吧，但是谁会卖力从一个地方迁移到另一个地方去构建家庭呢？
Are these the males or the females?
是男人还是女人？
We used our data to address this question, and at least in the last 300 years,
我们使用我们的数据解答了这个问题，至少在过去300年中，
we found that the ladies do the hard work of migrating from places to places to form families.
我们发现女性从一个地方迁移到另一个地方去构建家庭上是最辛苦的。
Now, these results are statistically significant, so you can take it as scientific fact that males are lazy.
这些结果在统计上很显著，所以你可以把男性懒惰当作科学事实。
We can move from questions about demography and ask questions about human health.
我们可以把问题从人口统计学开始转向人类健康问题。
For example, we can ask to what extent genetic variations account for differences in life span between individuals.
比如，我们可以问遗传变异能在多大程度上影响个体的寿命差异。
Previous studies analyzed the correlation of longevity between twins to address this question.
之前的研究通过分析双胞胎寿命的相关性来解答这个问题。
They estimated that the genetic variations account for about a quarter of the differences in life span between individuals.
他们估计出遗传变异对个体寿命差异的影响大约占1/4。
But twins can be correlated due to so many reasons, including various environmental effects or a shared household.
但双胞胎之间的关联有很多原因，包括多样的环境影响或共同的家庭。
Large family trees give us the opportunity to analyze both close relatives,
庞大的家谱树给了我们分析这些近亲，
such as twins, all the way to distant relatives, even fourth cousins.
比如双胞胎，到远房亲戚，甚至四代表亲这样的机会。
This way we can build robust models that can tease apart the contribution of genetic variations from environmental factors.
这样我们可以构建稳健的模型，从环境因素中分离出遗传变异的贡献来。
We conducted this analysis using our data,
我们使用数据执行了这个分析，
and we found that genetic variations explain only 15 percent of the differences in life span between individuals.
发现遗传变异只解释了15%的个体寿命差异。
That is five years, on average. So genes matter less than what we thought before to life span.
平均而言，就是5年之差。所以基因对寿命的重要性比我们之前想象的少。
And I find it great news, because it means that our actions can matter more.
我发现这是个好消息，因为这意味着我们的行动更为重要。
Smoking, for example, determines 10 years of our life expectancy -- twice as much as what genetics determines.
举个例子，吸烟会影响大约10年的预期寿命--是基因所能影响的两倍。
We can even have more surprising findings as we move from family trees
我们能有更多惊奇的发现，随着我们从家谱树展开，
and we let our genealogists document and crowdsource DNA information. And the results can be amazing.
让我们的家谱学专家建档，并且众包DNA信息。结果将是惊人的。
It might be hard to imagine,
可能令人难以想象，
but Uncle Bernie and his friends can create DNA forensic capabilities that even exceed what the FBI currently has.
伯尼叔叔和他的朋友能够创建DNA法医能力，甚至超过了FBI目前拥有的水平。
When you place the DNA on a large family tree, you effectively create a beacon that illuminates the hundreds of distant relatives
当你把DNA放在一棵大的家谱树中，你就有效地创造了一个照亮数百个远亲的灯塔，
that are all connected to the person that originated the DNA.
他们都与DNA的拥有者有联系。
By placing multiple beacons on a large family tree, you can now triangulate the DNA of an unknown person,
通过在一棵大的家谱树中放置不同的灯塔，你现在可以对一个陌生人的DNA进行三角测量，
the same way that the GPS system uses multiple satellites to find a location.
就跟GPS系统利用不同的卫星来定位一样。
The prime example of the power of this technique is capturing the Golden State Killer,
这种技术威力一个的主要例子是追捕“金州杀手”，
one of the most notorious criminals in the history of the US.
美国历史上最臭名昭著的罪犯之一。
The FBI had been searching for this person for over 40 years.
FBI已经寻找这人超过40年。
They had his DNA, but he never showed up in any police database.
他们有他的DNA，但他从未出现在警方的数据库中。
About a year ago, the FBI consulted a genetic genealogist,
大约一年前，FBI咨询了一位基因谱系学家，
and she suggested that they submit his DNA to a genealogy service that can locate distant relatives.
她建议他们提交他的DNA到可以定位远房亲戚的家谱服务平台上。
They did that, and they found a third cousin of the Golden State Killer.
FBI这样做了，他们找到了金州杀手的第三代表亲。
They built a large family tree, scanned the different branches of that tree,
他们构建了一棵巨大的家谱树，扫描树上的不同分支，
until they found a profile that exactly matched what they knew about the Golden State Killer.
直到他们找到完美匹配他们所了解的金州杀手信息的人。
They obtained DNA from this person and found a perfect match to the DNA they had in hand.
他们从这人身上取得DNA并发现跟他们手上的DNA一致。
They arrested him and brought him to justice after all these years.
过了这么些年，他们终于逮捕了他，并绳之与法。
Since then, genetic genealogists have started working with local US law enforcement agencies
自那之后，基因谱系学家开始跟美国当地执法机构合作，
to use this technique in order to capture criminals.
使用这种技术来抓捕罪犯。
And only in the past six months, they were able to solve over 20 cold cases with this technique.
仅仅在过去的6个月，他们使用这个技术就破获了超过20个铁证悬案。
Luckily, we have people like Uncle Bernie and his fellow genealogists These are not amateurs with a self-serving hobby.
幸好，我们有这群人，像伯尼叔叔和他的家谱学同行，他们不只是业余爱好者。
These are citizen scientists with a deep passion to tell us who we are.
他们是满怀热情的公民科学家，想要揭开我们所有人身份的秘密。
And they know that the past can hold a key to the future. Thank you very much.
他们知道，过去是通向未来的钥匙。谢谢大家。