來自這個古老文明的DNA，揭示了現(xiàn)代南亞人的祖先

來自這個古老文明的DNA，揭示了現(xiàn)代南亞人的祖先

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.

早在氣候變化迫使他們放棄繁榮昌盛的城市之前，一群狩獵采集者就以農(nóng)民的身份定居在印度河流域，伴隨著蓬勃發(fā)展的經(jīng)濟和長途貿(mào)易，形成了世界上最早的大規(guī)模城市社會。

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年達到頂峰，以其開創(chuàng)性的城鎮(zhèn)規(guī)劃、精心設(shè)計的排水系統(tǒng)和糧倉而自豪。他們是一個多元文化的社會，甚至有自己標準化的度量衡體系。但是，是什么誘使這些人一開始就徹底改變了他們原有的漫游方式呢?

"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.

來自哈佛大學(xué)的遺傳學(xué)家Reich在接受《科學(xué)警報》采訪時說：“主流觀點認為，農(nóng)業(yè)是通過伊朗農(nóng)民的大規(guī)模西進運動來到南亞的。”

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.

現(xiàn)代南亞人有伊朗血統(tǒng)的跡象，使研究人員懷疑，當這些古代伊朗人從中東的新月沃土(在那里發(fā)現(xiàn)了最早的農(nóng)耕證據(jù))遷移過來時，他們帶走了新的農(nóng)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，由印度德干學(xué)院考古學(xué)家瓦桑·辛德領(lǐng)導(dǎo)的研究小組剛剛推翻了這種設(shè)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.

在印度哈里亞納邦Rakhigarhi遺址的一個墓地里，研究小組第一次成功地對埋葬在這個古代文明遺跡中的一個人的基因組進行了測序。

(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.

雖然這個地方長期以來一直很受關(guān)注，但炎熱的南亞氣候為降解生物材料提供了完美的條件，幾乎沒有留下完整的DNA可供提取。但研究小組通過對這具4000至5000年歷史的遺骸進行100多次重新采樣，并將結(jié)果匯集起來，終于找到了足夠的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.

他們的分析表明，與這個人的伊朗血統(tǒng)相關(guān)的基因來自于這個地區(qū)的農(nóng)民和狩獵采集者彼此分離之前。Reich解釋說，這個人的伊朗祖先在農(nóng)業(yè)傳播到伊朗之前就離開了。

"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.

他說:“我們的研究表明，南亞的農(nóng)業(yè)要么是通過當?shù)氐陌l(fā)明，要么是通過吸收西方鄰國的思想(文化交流)，要么是通過某種結(jié)合而興起的。”

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.

將這個個體的基因組與即將發(fā)表在《科學(xué)》(Science)雜志上的另一項研究的基因組進行比較，研究小組還對這些古代文明之間的貿(mào)易和運動提供了一些見解。

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.

在從土庫曼斯坦的貢努爾和伊朗的shahr-i-sokhta采集的523個基因樣本中，有11個個體與南亞個體屬于同一基因群。

"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.

“這表明，這11個人是來自印度河流域文明移民的后代。”Reich說，這是有遺址之間的文化聯(lián)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解釋說：“哈拉帕人是古代世界最早的文明之一，也是印度文化和傳統(tǒng)的主要來源，但他們?nèi)绾闻c后來的人以及同時代的人聯(lián)系在一起一直是個謎。”

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.

雖然我們現(xiàn)在通過它們的城市遺跡和4000年的歷史遺跡了解它們，但這個最新測序的基因組顯示，古哈拉帕文明的遺產(chǎn)要豐富得多。

"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解釋說:“這個人被埋葬在印度河流域文明的墓地里，他們是今天幾乎所有南亞人最大的單一祖先來源。”

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.

當然，從一個人的基因組中能學(xué)到的東西太多了，所以研究人員希望他們所使用的技術(shù)，能讓他們研究哈拉帕文明中許多其他人的基因組，從而對這段豐富的歷史有一個更大的了解。

"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說:“我們還想研究南亞其他時期和地理位置的個體，特別是農(nóng)業(yè)出現(xiàn)前后的個體，以便了解基因變化在這些經(jīng)濟轉(zhuǎn)型中所伴隨的程度。”

Their findings have been published in Cell.

這一發(fā)現(xiàn)發(fā)表在《細胞》雜志上。