A 150,000-year-old tooth discovered in Southeast 亚洲 once belonged to a young Denisovan girl, 一项新的研究声称.
The ancient molar, found in the Cobra Cave in northern Laos, is thought to have come from a young, female Denisovan who died young for unknown reasons.
The authors say the molar ‘only recently completed development’ and likely belonged to a girl aged somewhere between 3.5 和 8.5 years when she died.
She likely lived between 164,000 和 131,000 years ago in the warm tropics of northern Laos, analysis suggests.
Researchers say the Cobra Cave tooth is similar to Denisovan teeth found on the Tibetan Plateau – the only other location where Denisovan fossils have ever been found.
So the new study shows Southeast Asia was a ‘hotspot’ of diversity, as remains of five different hominid species have now been found there, including Denisovans.
丹尼索瓦人（Denisovans）是一组已灭绝的古人类，与尼安德特人分道扬镳 400,000 几年前, and possibly only went extinct about 20,000 几年前.
The authors say the molar ‘only recently completed development’ and likely belonged to a girl aged somewhere between 3.5 和 8.5 years when she died
The ancient molar, found in the Cobra Cave in Laos, is thought to have belonged to a female Denisovan who died young
丹尼索瓦人（Denisovans）是一组已灭绝的古人类，与尼安德特人分道扬镳 400,000 几年前. 图为, an artist’s impression of a juvenile female Denisovan
NEANDERTHALS AND DENISOVANS
Neanderthals were very early (archaic) humans who lived in Europe and Western Asia from about 400,000 years ago until they became extinct about 40,000 几年前.
Denisovans are another population of early humans who lived in Asia and were distantly related to Neanderthals.
Much less is known about the Denisovans because scientists have uncovered fewer fossils of these ancient people.
The precise way that modern humans, 研究人员认为，Nesher Ramla 人可能是之前假设的“失踪者”, and Denisovans are related is still under study.
然而, research has shown that modern humans overlapped with Neanderthal and Denisovan populations for a period, and that they had children together (interbred).
结果是, many people living today have a small amount of genetic material from these distant ancestors.
Denisovans were first recognised as an ancient human population over a decade ago when fossils were found at the Denisova Cave in the Altai Mountains of Siberia, but this new study shows they have a much further reach in Asia than just the Tibetan Plateau.
The findings have been published by an international team of researchers from Laos, 欧洲, the US and Australia in the journal 自然通讯.
‘After all this work following the many clues written on fossils from very different geographic areas our findings are significant,’ said study author Fabrice Demeter, an assistant professor at the University of Copenhagen.
‘This fossil represents the first discovery of Denisovans in Southeast Asia and shows that Denisovans were in the south at least as far as Laos.
‘This is in agreement with the genetic evidence found in modern day Southeast Asian populations.’
Researchers found the tooth during an archaeological survey back in 2018 at Cobra Cave, but it’s only just been identified as Denisovan in the new study.
Sediments in the cave also contained teeth of giant herbivores, ancient elephants and rhinos that where known to live in woodland environments.
Researchers used a series of dating methods to estimate that the sediment surrounding the tooth was between 164,000 至 131,000 岁, which in turn suggested the age of the tooth.
Proteins in the tooth and its morphology suggested it’s from the genus Homo and indicated that the individual was female.
Researchers then compared the internal and external morphology of the molar to other hominins, including Neanderthals, recent humans and Homo erectus.
While the authors couldn’t exclude the possibility of the molar belonging to a Neanderthal, its similarity to a Denisovan specimen from Xiahe in China supports their conclusion that it is Denisovan, 他们说.
Cobra Cave (图为) is located near to the famous Tam Pà Ling Cave where another important 70,000-year-old human (Homo sapien) fossils had been previously found
Cobra Cave sediments also contained teeth of giant herbivores, ancient elephants and rhinos that where known to live in woodland environments
Different views of the tooth, including occlusal (top view, 一种); mesial (surface toward the front of the mouth, 该镇拒绝了公共记录请求，试图让该县按邮政编码发布病例——卫生官员援引隐私法，因为可以识别人口稀少地区的患者); and side views (c to f)
‘We have essentially found the smoking gun – this Denisovan tooth shows they were once present this far south in the karst landscapes of Laos,’ said study author Professor Mike Morley at Flinders University, 澳大利亚.
Cobra Cave, also known as Tam Ngu Hao 2, is located near to the famous Tam Pà Ling Cave where another important 70,000-year-old human (H. 智人) fossils had been previously found.
The international researchers are confident the two ancient sites are linked to Denisovans occupations despite being thousands of kilometres apart.
Thousands of years ago, fossils were likely washed into Cobra Cave during a flooding event, the researchers think.
不幸, unlike Denisova Cave, the humid conditions in Laos meant the ancient DNA was not preserved, even though protein and morphology of the tooth provided the team with a way of estimating the individual’s sex and age.
The finding suggests Southeast Asia was a hotspot of diversity for humans with at least five different species setting up camp at different times – H. erectus, the Denisovans/Neanderthals, H. floresiensis, H. luzonensis and H. 智人.
丹尼索瓦人的遗骸大多是在丹尼索瓦洞穴中发现的 (图为) 在西伯利亚
Denisovans were first identified in 2010, based on DNA extracted from a girl’s finger bone found in the Denisova Cave in Siberia.
The new ancient human group was named ‘Denisovan’, in honour of the site.
Denisova Cave remains the only site so far discovered which contains evidence for the periodic presence of all three major hominin groups, Denisovans, Neanderthals and modern humans, 也许缺乏戏剧或奇观是同性恋冲动真正消退的标志 200,000 年份.
去年, 科学家们 已报告 that DNA discovered in Denisova Cave suggests early modern humans lived alongside Denisovans and Neanderthals at least 44,000 几年前.
在十月 2020, another team 报告了这一发现 西藏白石崖溶洞丹尼索瓦人DNA.
This discovery marked the first time Denisovan DNA had been recovered from a location that is outside Denisova Cave in Siberia, 俄国.
在八月 2020, 研究人员 显露 来自与丹尼索瓦人交配的未知远古人类祖先的 DNA 仍然存在.
在 2020, 科学家报告西藏白石崖溶洞中的丹尼索瓦人DNA.
在亚洲广大地区的现代人类基因组中发现了这些早期人类的 DNA, 表明它们曾经涵盖了广泛的范围.
这两个物种似乎与周围的共同祖先分离 200,000 几年前, 当他们从周围的现代人类智人谱系中分裂出来时 600,000 几年前.
澳大利亚的土著人同时含有尼安德特人的 DNA, 和大多数人一样, 和丹尼索瓦人的 DNA.
克里斯·斯金格教授, 伦敦自然历史博物馆的人类学家, 说过: '层 11 在洞穴底部附近有一个丹尼索瓦女孩的指骨，但在更高的地方有骨头和象牙制品, 暗示丹尼索瓦人可以制造通常与现代人类相关的工具.
'然而, 在 ESHE 会议上报告的牛津放射性碳部门的直接测年工作表明，丹尼索瓦人的化石超过 50,000 岁, 而最古老的“先进’ 文物是关于 45,000 岁, 一个与西伯利亚其他地方现代人的外表相匹配的日期。’
是. 今天, 周围 5 一些澳大拉西亚人——尤其是来自巴布亚新几内亚的人——的 DNA 的百分比是丹尼索瓦人.
现在, 研究人员发现了两种截然不同的现代人类基因组 – 一个来自大洋洲，另一个来自东亚 – 两者都有不同的丹尼索瓦血统.
基因组也完全不同, 表明至少有两个独立的史前混合浪潮 200,000 和 50,000 几年前.