肯尼亚发现最古老石器
作者：赵熙熙 来源：中国科学报 发布时间：2015-4-20
本报讯 研究人员在日前于美国加利福尼亚州旧金山召开的一次会议上表示，他们已经发现了由人类祖先制造的迄今最古老的工具——距今约330万年的石片。这一时间比之前已知最古老的工具还要早70万年，表明人类祖先在人属出现之前的几十万年便已经能够制造工具。一旦得到确认，新的证据将能够证实有关早期工具使用的有争议的假设，同时表明古老的更新纪灵长类动物——例如著名的“露西”——或许也能够制造工具。
直到现在，已知最早的石器发现于埃塞俄比亚的贡纳，距今约260万年。这些石器属 于一种被称为奥尔德沃文化的工具制造技术。之后，在2010年，研究人员在埃塞俄比亚迪基卡发现的动物骨骼上的砍切痕迹可以追溯至距今340万年前，他们 推测，是使用工具的人类祖先制造了这些线状标记。然而这一假设立即引发了争议，一些学者提出，这些痕迹可能是被人类或其他动物踩踏而产生的。由于没有发现真正的工具，这一争论似乎将持续下去而没有结论。
如今，这些缺失的工具终于被找到了。
在于旧金山举行的古人类学会年会上，纽约州石溪大学考古学家Sonia Harmand描述了在洛迈奎3号遗址——位于肯尼亚图尔卡纳湖以西——发现的大量史前工具。
2011年，Harmand曾率领研究人员寻找在1998年发现一个有争议的人类“近亲”——肯尼亚平脸人的遗址。然而他们走错了方向，在出土肯尼亚平脸人的不远处偶然发现了名为洛迈奎的另一个区域。研究人员随后在这里的沙地表层发现了Harmand所谓的“明显的石器”，并立即开始了小规模的发掘工作。
研究人员在地下发现了更多的史前工具，例如石核、石片等。研究人员在第二年又返回这里进行了挖掘工作，如今已找到近20件保存完好的石片、石核和石砧——所有这些石器都埋藏在一个能够为年代测定提供安全背景的沉积层中。Harmand介绍说，在地表还发现了其他130件石器碎片。
Harmand在此次会议上表示：“这些史前石器显然是故意敲打后的产物而非岩石偶然破裂的结果。”利用古地磁技术对埋藏这些史前石器的沉积层进行测年分析显示，其具有330万年的历史。
Harmand在她的演讲中指出，尽管最近的研究将人属的起源时间推至距今280万年前，但这些工具依然太过古老而不可能是由第一批完全成熟的人类所制造的。她推断，最可能的解释是，这些石片是由类似于“露西”的更新纪灵长类动物或肯尼亚平脸人制造的。然而无论是哪一种方式，工具制造显然在人属诞生之前便已出现了。
Harmand表示，她和同事建议将这些新工具称为洛迈奎技术，因为它们与奥尔德沃文化太过遥远以及差别太大。
亲眼见过这些史前石器的研究人员对于这项 提议非常热衷。华盛顿哥伦比亚特区乔治华盛顿大学人类学家AlisonBrooks认为，这一发现“令人兴奋”。“它们并非由自然力产生的……同时测年证据是相当可靠的。”Brooks也赞同这些工具太古老了，因此不可能是 由人属制造的，这意味着“技术在人属生物的出现过程中扮演了一个重要的角色”。
对于在迪基卡动物骨骼上发现砍切痕迹的加利福尼亚科学院古人类学家Zeresenay Alemseged来说，这一发现也很让人欣喜。Alemseged说：“迪基卡的切痕让我们拥有了史前石器的牺牲品，而Harmand的发现为我们提供了确凿的证据。”（赵熙熙）
《中国科学报》(2015-04-20 第2版 国际)
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按：原文将Homo 误译为“智人”，改为“人属”。

World’s oldest stone tools discovered inKenya

The shores of Lake Turkana, where manyfossils of human ancestors have been found, are also the home of what may bethe oldest known tools.
By
Michael Balter
14 April 2015 5:30 pm
SAN FRANCISCO, CALIFORNIA—Researchers at a meeting here say they have found the oldest toolsmade by human ancestors—stone flakes dated to 3.3 million years ago. That’s700,000 years older than the oldest-known tools to date, suggesting that ourancestors were crafting tools several hundred thousand years before our genus Homoarrived on the scene. If correct, the new evidence could confirm disputedclaims for very early tool use, and it suggests that ancient australopithecineslike the famed “Lucy” may have fashioned stone tools, too.
Until now, the earliest known stone toolshad been found at the site of Gona in Ethiopia and were dated to 2.6 millionyears ago. These belonged to a tool technology known as the Oldowan, so calledbecause the first examples were found more than 80 years ago at Olduvai Gorgein Tanzania by famous paleoanthropologists Louis and Mary Leakey. Then, in2010, researchers working at the site of Dikika in Ethiopia—where anaustralopithecine child was also discovered—reported cut marks on animal bonesdated to 3.4 million years ago; they argued that tool-using human ancestorsmade the linear marks. The claim was immediatelycontroversial, however, and some argued that what seemed to be cut marksmight have been the result of trampling by humans or other animals. Without thediscovery of actual tools, the argument seemed likely to continue withoutresolution.
Now, those missing tools may have beenfound. In a talk at the annual meeting of the Paleoanthropology Society here,archaeologist Sonia Harmand of Stony BrookUniversity in New York described the discovery of numerous tools at the site of Lomekwi 3, just west of Lake Turkana in Kenya, about1000 kilometers from Olduvai Gorge. In 2011, Harmand’s team was seeking thesite where a controversialhuman relative called Kenyanthropus platyops had been discovered in1998. They took a wrong turn and stumbled upon another part of the area, calledLomekwi, near where Kenyanthropus had been found. The researchersspotted what Harmand called unmistakable stone tools on the surface of thesandy landscape and immediately launched a small excavation.
More tools were discovered under theground, including so-called cores from which human ancestors struck off sharpflakes; the team was even able to fit one of the flakes back to its originalcore, showing that a hominin had crafted and then discarded both core and flakein this spot. The researchers returned for more digging the following year andhave now uncovered nearly 20 well-preserved flakes, cores, and anvilsapparently used to hold the cores as the flakes were struck off, all sealed insediments that provided a secure context for dating. An additional 130 pieceshave also been found on the surface, according to the talk.
“The artifacts were clearly knapped[created by intentional flaking] and not the result of accidental fracture ofrocks,” Harmand told the meeting. Analysis of the tools showed that they hadbeen rotated as flakes were struck off, which is also how Oldowan tools werecrafted. The Lomekwi tools were somewhat larger than the average Oldowanartifacts, however. Dating of the sediments using paleomagnetictechniques—which track reversals in Earth’s magnetic field over time and havebeen used on many hominin finds from the well-studied Lake Turkana area—putthem at about 3.3 million years old.
Although very recent research has now pushed backthe origins of the genus Homo to as early as 2.8 million years ago,the tools are too old to have been made by the first fully fledged humans,Harmand said in her talk. The most likely explanation, she concluded, was thatthe artifacts were made either by australopithecines similar to Lucy or by Kenyanthropus.Either way, toolmaking apparently began before the birth of our genus. Harmandand her colleagues propose to call the new tools the Lomekwian technology, shesaid, because they are too old and too distinct from Oldowan implements torepresent the same technology.
Researchers who have seen the tools inperson are enthusiastic about the claim. The finds are “very exciting,” saysAlison Brooks, an anthropologist at George Washington University in Washington,D.C. “They could not have been created by natural forces … [and] the datingevidence is fairly solid.” She agrees that the tools are too early to have beenmade by Homo, suggesting that “technology played a major role in theemergence of our genus.”
The claim also looks good topaleoanthropologist Zeresenay Alemseged of the California Academy of Scienceshere, a leader of the team that found cut marks on the Dikika animal bones. (Atthe meeting, another team member presented new arguments for the cut marks’authenticity.) “With the cut marks from Dikika we had the victim” of the stonetools, Alemseged says. “Harmand’s discovery gives us the smoking gun.”
Posted in Africa, Archaeology Human Evolution
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Science|DOI: 10.1126/science.aab2487

Meetings Version of the Paleoanthropology Abstracts
San Francisco, CA, 14–15 April 2015
(Please note that the meetings version is not the official publication; abstracts
will be published in our on-line journal, PaleoAnthropology, in May 2015)
[abstracts below have been only minimally copy-edited, as this is not the published version]
Harmand et al.
Early tools from West Turkana, Kenya
Recently, there has been increasing openness in paleoanthropology to the possibility of hominin tool manufacture before 2.6 Ma. The earliest artifacts from the sites of Gona, Hadar, and Omo in Ethiopia, and especially Lokalalei 2C in Kenya already demonstrate hominin knappers’ planning depth, spatial coordination, manual dexterity, and raw material selectivity. It has been argued that artifacts before 2.6 Ma might be of too low densities or that archaeologists haven't recognized such stone tools because they might not directly resemble known Oldowan lithics. In 2011, the West Turkana Archaeological Project began new survey in the Lomekwi member (3.44-2.53 Ma) of the Nachukui Formation in Kenya, to search for evidence of earlier hominin lithic behavior. We report the discovery of Lomekwi 3 (LOM3), an archaeological site where stone artifacts have been found in situ in spatiotemporal association with Pliocene hominin fossils and from a wooded environment. The LOM3 knappers, with a developing understanding of the fracture properties of stone, and using simple bipolar and passive hammer techniques, were combining battering activities with core reduction. The LOM3 tools mark a new beginning to the known archaeological record.

真是无巧不成书，今年1月Science刚发了一篇文章，从化石对比的角度论证早于300万年的南方古猿很可能具有使用工具的能力。才过了几个月，这边就报出消息发现了300多万年的石器……
还是国家地理的资讯：
Human Ancestors May Have Used Tools Half-Million Years Earlier Than Thought
Fossil hand bones show evidence of tool use more than three million years ago.

By Dan Vergano, National Geographic
PUBLISHEDJanuary 22, 2015

Who swung the first hammer stone? Earlyhuman ancestors may have hefted tools more than three million years ago,ancient hand bones suggest. That’s roughly half a million years earlier thanthe oldest stone tools yet discovered.
The hand-bone analysis, led by the UnitedKingdom’s MatthewSkinner of the University of Kent in Canterbury, compared the internalstructure of hand bones from modern people, chimps, apes, Neanderthals, andearly human species.
Most notably in thestudy, released Thursday by the journal Science, researchers reporton the hands of Australopithecus africanus, best known from the piercedskull of the famed “Taungchild,” who may have been killed by an eagle about 2.5 million years ago.
While the pattern of spongy bone in apehands doesn’t show signs of humanlike uses such as pinching or hammer holding,the researchers write, the hand bones of Australopithecus do. Ratherthan bones for knuckle-walking or tree climbing, under the palms of these earlyhumans were anchor bones “consistent with forceful opposition of the thumb andfingers typically adopted during tool use.”
Why It Matters
Human-origins experts have long argued overthe timing of the first tools, seeing in them the earliest expression of auniquely human mode of survival. For decades, the earliest known stone toolswere associated with their presumed maker, an ancestor less than two millionyears old called Homo habilis, or “Handy Man.”
In 2000, scientists announced the discoveryof 2.6-million-year-old tools in Ethiopia, pushing this pivotal moment inprehistory back more than half a million years. Cut marks on animal bones inEthiopia dated to 3.4 million years ago may also suggest tool use, but this hasbeen debated. The current study supports that earlier origin.

Top row: First metacarpals of the thumb in various primates. Bottom row: 3-D renderings from the micro-CT scans of the same specimens, showing a cross-section of the structure inside.

The Big Picture
Experiments suggest that pinching sharp flakes of stone to use “to remove meat from the bone,” says the study, puts the biggest demands on the precision grip. Finding hand bones with internal structure molded by that behavior throughout life is a much better way of discerning when this critical step in our evolution took place than looking at the external shape of hand bones, as previous studies have done.
What’s more, the study shows a way to reveal tool use in our ancestors even when no actual tools are found.
What’s Next
The study findings suggest that our ancestors were using stone tools at least three million years ago, opening up new opportunities for archaeologists to search for the stone tools themselves.
Follow Dan Vergano on Twitter.

Illustration of the species Homo habilis (genus Homo between 2.1 and 1.5 million years ago) shaping a tool by “knapping”. Credit: Vassar.edu

最近正看到这里。东非，人类发源地。