来自这个古老文明的DNA，揭示了现代南亚人的祖先
Long before climate change drove them to abandon their thriving cities, a group of hunter-gatherers settled in the Indus River Valley as farmers, leading to the creation of one of the world's first large-scale urban societies, complete with booming economies and long-distance trade.
早在气候变化迫使他们放弃繁荣昌盛的城市之前，一群狩猎采集者就以农民的身份定居在印度河流域，伴随着蓬勃发展的经济和长途贸易，形成了世界上最早的大规模城市社会。
The Harappan civilisation, which peaked around 2,600 to 1,900 BCE, boasted pioneering town planning, elaborate drainage systems and granaries. They were a multicultural society and even had their own standardised system of weights and measures. But what enticed these people to drastically change their roaming ways in the first place?
哈拉帕文明在公元前2600年到1900年达到顶峰，以其开创性的城镇规划、精心设计的排水系统和粮仓而自豪。他们是一个多元文化的社会，甚至有自己标准化的度量衡体系。但是，是什么诱使这些人一开始就彻底改变了他们原有的漫游方式呢?
"A mainstream view is that farming came to South Asia through the large-scale westward movement of Iranian farmers," geneticist David Reich from Harvard University told ScienceAlert.
来自哈佛大学的遗传学家Reich在接受《科学警报》采访时说：“主流观点认为，农业是通过伊朗农民的大规模西进运动来到南亚的。”
Hints of Iranian ancestry in modern South Asians led researchers to suspect that when these ancient Iranians migrated from the Fertile Crescent in the Middle East (where the earliest evidence of farming has been found), they took their new agricultural way of life with them.
现代南亚人有伊朗血统的迹象，使研究人员怀疑，当这些古代伊朗人从中东的新月沃土(在那里发现了最早的农耕证据)迁移过来时，他们带走了新的农耕生活方式。
But a team of researchers led by archaeologist Vasant Shinde from Deccan College in India has just up-ended that scenario's timeline.
但是，由印度德干学院考古学家瓦桑·辛德领导的研究小组刚刚推翻了这种设想。
For the first time, the team successfully sequenced a genome from an individual found buried in this ancient civilisation's remains, in a cemetery at the site of Rakhigarhi in Haryana, India.
在印度哈里亚纳邦Rakhigarhi遗址的一个墓地里，研究小组第一次成功地对埋葬在这个古代文明遗迹中的一个人的基因组进行了测序。
(Vasant Shinde/Deccan College Post Graduate Research Institute)
While this site has long been of interest, the hot South Asian climate provides the perfect conditions for degrading biological material, leaving little intact DNA to extract. But the team managed to find enough DNA from the 4,000 to 5,000 year old remains by re-sampling the skeleton over 100 times and pooling the results.
虽然这个地方长期以来一直很受关注，但炎热的南亚气候为降解生物材料提供了完美的条件，几乎没有留下完整的DNA可供提取。但研究小组通过对这具4000至5000年历史的遗骸进行100多次重新采样，并将结果汇集起来，终于找到了足够的DNA。
Their analysis showed that the genes associated with this individual's Iranian ancestry came from before the time when farmers and hunter-gatherers in the area separated from each other. This individual's Iranian ancestors left before farming spread through Iran, explained Reich.
他们的分析表明，与这个人的伊朗血统相关的基因来自于这个地区的农民和狩猎采集者彼此分离之前。Reich解释说，这个人的伊朗祖先在农业传播到伊朗之前就离开了。
"Our study says that farming arose in South Asia either through local invention or adoption of ideas from western neighbours (cultural communication) or some combination," he said.
他说:“我们的研究表明，南亚的农业要么是通过当地的发明，要么是通过吸收西方邻国的思想(文化交流)，要么是通过某种结合而兴起的。”
Comparing this individual's genome with those from another study about to be published in Science, the team also provided some insights into the trade and movements between these ancient civilisations.
将这个个体的基因组与即将发表在《科学》(Science)杂志上的另一项研究的基因组进行比较，研究小组还对这些古代文明之间的贸易和运动提供了一些见解。
Eleven individuals out of 523 genetically sampled from Gonur in Turkmenistan and Shahr-i-Sokhta in Iran belonged to the same genetic group as the South Asian individual.
在从土库曼斯坦的贡努尔和伊朗的shahr-i-sokhta采集的523个基因样本中，有11个个体与南亚个体属于同一基因群。
"This suggests that these 11 individuals were migrants or recent descendants of migrants from the Indus Valley Civilisation," Reich said, which is supported by the cultural connections seen between the sites.
“这表明，这11个人是来自印度河流域文明移民的后代。”Reich说，这是有遗址之间的文化联系支持的。
(Shinde et al. Cell, 2019)
"The Harappans were one of the earliest civilisations of the ancient world and a major source of Indian culture and traditions, and yet it has been a mystery how they related both to later people as well as to their contemporaries," Shinde explained.
Shinde解释说：“哈拉帕人是古代世界最早的文明之一，也是印度文化和传统的主要来源，但他们如何与后来的人以及同时代的人联系在一起一直是个谜。”
While we now know them through their urban remains and 4,000 year old relics, this newly sequenced genome revealed the ancient Harappan civilisation has a much greater legacy.
虽然我们现在通过它们的城市遗迹和4000年的历史遗迹了解它们，但这个最新测序的基因组显示，古哈拉帕文明的遗产要丰富得多。
"This individual buried in an Indus Valley Civilisation cemetery, was part of a population that is the single largest source of ancestry in nearly all South Asians today," explained Reich.
Reich解释说:“这个人被埋葬在印度河流域文明的墓地里，他们是今天几乎所有南亚人最大的单一祖先来源。”
Of course there's only so much that can be learnt from one individual's genome, so the researchers hope the technique they used will allow them to study the genomes of many other individuals from the Harappa civilisation to create a bigger picture of this rich history.
当然，从一个人的基因组中能学到的东西太多了，所以研究人员希望他们所使用的技术，能让他们研究哈拉帕文明中许多其他人的基因组，从而对这段丰富的历史有一个更大的了解。
"We also want to study individuals from other time periods and geographic locations in South Asia," Reich said, "particularly just before and after the advent of farming in order to understand the extent to which genetic change accompanied these economic transformations."
Reich说:“我们还想研究南亚其他时期和地理位置的个体，特别是农业出现前后的个体，以便了解基因变化在这些经济转型中所伴随的程度。”
Their findings have been published in Cell.
这一发现发表在《细胞》杂志上。
