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人類學 – 開欄文
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林德索人消失之謎可能有解 -- Katie Hunt
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Cave discovery in France may explain why Neanderthals disappeared, scientists say
Katie Hunt, CNN, 09/12/24
When archaeologist Ludovic Slimak unearthed five teeth in a rock shelter in France’s Rhône Valley in 2015, it was immediately obvious that they belonged to a Neanderthal, the first intact remains of the ancient species to be discovered in that country since 1979.
However, the once-in-a-lifetime find, nicknamed Thorin after a character in “The Hobbit,” remained a well-kept secret for almost a decade while Slimak and his colleagues untangled the significance of the find — a fraught undertaking that pitted experts in ancient DNA against archaeologists.
“We faced a major issue,” said Slimak, a researcher at France’s National Centre for Scientific Research and Paul Sabatier University in Toulouse. “The genetics was sure the Neanderthal we called Thorin was 105,000 years old. But we knew by (the specimen’s) archaeological context that it was somewhere between 40,000 to 50,000 years old.”
“What the DNA was suggesting was not in accordance with what we saw,” he added.
It took the team almost 10 years to piece together the story of the puzzling Neanderthal, adding a new chapter in the long-standing mystery of why these humans disappeared around 40,000 years ago.
The research, published Wednesday in the journal Cell Genomics, found that Thorin belonged to a lineage or group of Neanderthals that had been isolated from other groups for some 50,000 years. This genetic isolation was the reason Thorin’s DNA seemed to come from an earlier time period than it actually did.
Until now, geneticists thought that at the time of extinction there was one Neanderthal population that was genetically homogeneous, but the new study reveals at least two populations were present in Western Europe at that time — and they lived surprisingly close to each other.
“The Thorin population spent 50,000 years without exchanging genes with other Neanderthal populations,” Slimak said in a news release.
“We thus have 50 millennia during which two Neanderthal populations, living about ten days’ walk from each other, coexisted while completely ignoring each other.”
Slimak said that the discovery suggested that Neanderthal communities were small and insular — factors that could be key to understanding their extinction because isolation is generally considered to be an evolutionary disadvantage.
Less genetic variation could make it harder to adapt to changing climate or disease, while less social interaction between groups makes it harder to share knowledge and technology.
“They were happy in their valley and did not need to move, while Homo sapiens all the time they want to explore, to see what is there after this river, after this mountain. (We have) this need, this need to move, and this need to build a social network,” Slimak said.
This pattern of small populations, isolated culturally and genetically from one another, was likely a major factor behind Neanderthal extinction, which occurred around the same time Homo sapiens arrived in Europe, he said.
DNA from Homo sapiens fossils from that time show that these early arrivals interbred with Neanderthals — traces of those encounters remain in present-day human populations. However, no corresponding genetic evidence of that interbreeding has been found in Neanderthal fossils from that time, including Thorin’s remains, the study noted.
Whatever behavior led to this lack of genetic intermingling on one side, along with small and isolated Neanderthal populations such as the one Slimak and his colleagues identified, likely contributed to the disappearance of the Neanderthals, said Chris Stringer, research lead in human evolution at London’s Natural History Museum who wasn’t involved in the study.
“Whatever the reasons for this imbalance (social, biological?) it contributed to the demise of the last Neanderthals, since their already small populations were losing reproductive age individuals to the other species, without any replenishment in return,” Stringer said via email.
“Coupled with economic competition from the newcomers over resources, this could have been a recipe for demographic collapse.”
It’s not clear whether Thorin’s full skeleton is interred within Grotte Mandrin, as the rock shelter in the Rhône Valley near Malataverne, France, is known. The remains were found near the surface in soft, unstable ground, and the excavation continues slowly, Slimak said, with archaeologists tweezing out “one grain at a time.” It’s also unclear whether the specimen, which is male, was deliberately buried or not.
Archaeologists have excavated more of Thorin’s remains: 31 teeth, part of the jaw and five finger bones, so far. The shape of his teeth is typical of a Neanderthal, but he had two extra lower molars — a trait sometimes suggestive of an inbred population, the study noted.
Genetic mystery resolved
The initial genetic analysis suggested that Thorin was much older because his genome was distinct from other later Neanderthals, resembling the genomes of ancient humans who lived more than 100,000 years ago.
To understand Thorin’s origins and confirm the age of his remains, the team analyzed chemical isotopes in his bones and teeth to infer what type of climate he lived in based on the water he would have drunk and other factors. A Neanderthal in Europe 105,000 years ago would have a enjoyed a much warmer climate than one living 45,000 years ago during the Ice Age.
“We worked for seven years to find out who was wrong — archaeologists or genomicists,” Slimak said in the news release.
Slimak has been involved in the excavation of Grotte Mandrin for more than three decades and made a number of exciting finds at the rock shelter. It’s the only known site to have been home to alternating groups of both Homo sapiens and Neanderthals, plus the earliest evidence of bow and arrow use outside Africa.
“Grotte Mandrin keeps delivering surprises,” Stringer said.
For more CNN news and newsletters create an account at CNN.com
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史前人的智慧 -- Darren Orf
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此之謂：「窮則變；變則通」；或：「需要為發明之母」。
Archaeologists Figured Out How Early Humans Killed Ice Age Mammoths. It’s Not How You Think.
190(ish) pounds versus six tons isn’t exactly a fair fight—but our earliest ancestors evened the playing field.
Darren Orf, 08/29/24
* Depictions of ancient humans in both scientific and popular culture contexts picture them throwing spears at the thick hides of mammoths.
* A new study from archaeologists at UC Berkeley suggests that Pleistocene hunters likely used planted pikes, topped with sharp Clovis points, to kill megafauna like mammoths, mastodons, and even saber-toothed cats.
* This theory shows how this system would’ve acted like an ancient hollow-point bullet and delivered a more devastating blow compared to a thrown spear.
It’s been long suggests that the arrival of Homo sapiens in the Americas caused (or at very least contributed to) the disappearance of megafauna like mammoths through overhunting—but how exactly did a collection of small, fragile humans take down these four-to-six ton behemoths some 13,000 years ago?
The typical depiction of humans hunting mammoths toward the tail of the Pleistocene imagines them chucking spears, tipped with sharp rocks known as Clovis points, as the beasts rear up on their hind legs in fury, but a new study from archaeologists at UC Berkeley think that ancient humans likely worked smarter, not harder.
Instead of throwing spears, which likely would’ve had little impact force on the animal, this new study published in the journal PLOS One says that hunters likely planted their spears in the ground and waited for charging mastodons, bison, or even saber-toothed cats to impale themselves upon the fearsome spiked tips. This would have driven the spear much deeper into the animals, almost acting like a modern hollow-point bullet, according to the researchers.
“This ancient Native American design was an amazing innovation in hunting strategies,” UC Berkeley’s Scott Byram, first author of the study, said in a press statement. “This distinctive Indigenous technology is providing a window into hunting and survival techniques used for millennia throughout much of the world.”
This mystery initially began with the discovery of Clovis points, an array of various-sized sharp rocks made from material like flint or jasper that use fluted indentations at the base of the stone. This rock is one of the most common archaeological items found during this period, but experts weren’t exactly sure how they used them, as the Clovis point is usually the only part of the weapon system that survives the ravages of time.
After analyzing historical records of people hunting or fighting with planted pikes, the team also designed a test platform to see how much force a spear could withstand before snapping. Similar experiments that launched spiked weapons at ballistic gels showed that a spear, thrown at an animal like a mastodon, would’ve felt like little more than a pinprick, the researchers say. But the foreshaft collapse following the Clovis point's entry into an animal’s hide likely would’ve increased the damage.
“The kind of energy that you can generate with the human arm is nothing like the kind of energy generated by a charging animal,” UC Berkeley’s Jun Sunseri, a co-author of the study, said in a press statement. “It’s an order of magnitude different. These spears were engineered to do what they’re doing to protect the user.”
This new theory also supports another idea surrounding Clovis points, which is that they’re very time-consuming to make and also more resource-intensive than typical arrowheads. This means it’s unlikely that an ancient hunter could want to waste such a resource on an attack method with a low success rate.
“Sometimes in archaeology,” Byram said, “the pieces just start fitting together like they seem to now with Clovis technology, and this puts pike hunting front and center with extinct megafauna. It opens up a whole new way of looking at how people lived among these incredible animals during much of human history.”
Although the strategy behind ancient humans’ megafauna hunting efforts appears to be coalescing, Byram and his team want to conduct a more realistic test involving a replica mammoth to simulate what would happen if a charging animal ran directly into this theorized pike system. However, because archaeologists only find Clovis points and not the accompanying weapon system, it's difficult to know for sure if such a system was used.
If it works as expected, we’ll need to rewrite our understanding of how indigenous peoples survived and thrived in the Americas 13,000 years ago and beyond.
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新定時技術有助於了解早期人類史 -- Aristos Georgiou
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Major' Archaeological Development May Help Rewrite Early Human History
Aristos Georgiou, 06/09/24
An innovative technique used in a study of Neanderthal hearths—places where fires were created—has been described by researchers as a "major" development in archaeology, one that could help shed light on prehistoric humans' behavior.
For a study published in the journal Nature, an interdisciplinary team of researchers found that a series of six Neanderthal hearths at El Salt, a Paleolithic site in Spain, were formed over at least 200 to 240 years, with each one likely having been created decades apart.
The findings are significant because determining the timescale of human activity in the Paleolithic period, also known as the Old Stone Age, has long been one of the most challenging problems in prehistoric archaeology. (This period in human prehistory extends from the earliest use of stone tools more than 3 million years ago to around 12,000 years ago.)
Resolving the timescale of such activity is difficult largely because of the limitations of dating techniques. For example, radiocarbon techniques cannot date samples that are older than around 50,000 to 60,000 years. Meanwhile, other techniques can produce errors of several thousand years.
Researcher Santiago Sossa-Ríos examines a hearth at El Salt, an archaeological site in Spain. Researchers have used an innovative technique to shed light on the chronology of six Neanderthal hearths at the site. SVEN KLEINHAPL/UNIVERSITY OF VALENCIA 請至原網頁觀看照片
"Although it has been proposed that Paleolithic hunter-gatherers were highly mobile, key aspects of their lifestyle, such as the time between camps and the size of traveling groups, remain unclear," the study's authors wrote. "Complexity in the formation of Paleolithic sites makes it difficult to single out human occupation episodes and resolve the time between them."
In the latest study, the research team—led by Ángela Herrejón-Lagunilla of Spain's University of Burgos—attempted to address this problem by examining hearths at El Salt, dated to around 52,000 years ago, with an innovative technique.
The technique involved a combination of "archaeostratigraphic" analyses—which helped the team determine the order the hearths were created in, based on their relative position in the ground layers—and an approach known as archaeomagnetic dating.
This technique studies and interprets signatures of the Earth's past magnetic field as recorded in burned archaeological remains. The approach works, given that burnt materials hold a record of the direction and/or intensity of the magnetic field at the time of the last fire.
The combination of the two approaches revealed that the Neanderthal hearths at El Salt were created decades or even up to a century apart—a finding that sheds light on the behavior of these early humans, who went extinct around 40,000 years ago. The results provide an indication of the timing of the hearths in unprecedented resolution.
"When we excavate archaeological settlement areas, we assume that they are the result of many events of human activity, but until now we did not know exactly how much time had passed between these activities. We did not know whether it was decades, centuries or thousands of years," said Santiago Sossa-Ríos, a researcher in prehistory, archaeology and ancient history at Spain's University of Valencia and an author on the study, in a press release.
"From there, within this temporary framework, we can open up new lines of investigation to study, for example, patterns of mobility, technological change or differences in the use of space," he continued. "The time is there, the challenge lies in combining and extracting everything that the methods offer us to uncover it."
Hearths can yield useful information about Neanderthal life because they are good indicators of occupation within a given site.
The new findings indicate that while Neanderthals were highly mobile, in some cases they may have returned to previous settlements after lengthy periods but still within the space of individual lifetimes.
In Paleolithic archaeology, a discipline in which human behavior is usually studied on long timescales typical of geological processes, being able to observe changes on timescales closer to a human lifespan is a significant development.
As a result, the techniques employed in the study could help to shed light on Paleolithic hunter-gatherers. They could even be applied to other archaeological contexts to resolve the timings of human activity.
"It is definitely a major step forward in archaeology, which will help us to better understand human behavior in the past," the study's authors said in the press release.
Aristos Georgiou is a Newsweek science reporter with the London, U.K., bureau. He reports on science and health topics, including; animal, mental health, and psychology-related stories. Aristos joined Newsweek in 2018 from IBTimes UK and had previously worked at The World Weekly. He is a graduate of the University of Nottingham and City University, London. Languages: English. You can get in touch with Aristos by emailing a.georgiou@newsweek.com.
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現代人和林德索人混血兒 ---- BENJAMIN TAUB
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How A Human-Neanderthal Hybrid Child Rewrote Human History
Our family tree is much messier than we thought.
BENJAMIN TAUB, Edited by Laura Simmons, 05/08/24
The Lapedo Child has a modern human jaw but Neanderthal limbs. Image credit: Microgen/Shutterstock.com (請至原網頁觀看相關照片)
Around 24,500 years ago, the body of a 4-year-old child was wrapped in an ochre-dyed shroud and lowered into a burial pit in the Lapedo Valley of central Portugal. Unlike any whippersnapper alive today, however, this extraordinary child exhibited a unique blend of modern human and Neanderthal features, disproving everything we thought we knew about the history of our species.
Known as the Lapedo Child, the youngster’s complete skeleton was discovered in 1998. Until then, anthropologists had assumed that modern humans evolved in East Africa before spreading across Eurasia and replacing the more archaic hominids that lived there – including Neanderthals.
This narrative supposed that we and our ancient relatives were completely separate species that could not interbreed, and that our expansion resulted in the extinction of our more primitive cousins. The Lapedo Child ripped up this script, prompting the discoverers to propose that modern humans did mate with Neanderthals, and that the genetic code of this extinct species persisted within the hybrid lineage that flowed from the loins of our cross-pollinating ancestors.
Thought to have been a male, the child himself possessed the chin and inner ear of an anatomically modern human, along with the stocky frame and limbs of a Neanderthal. Such a finding initially sent shockwaves through the anthropological world, sparking fierce debate as to what this all meant for human history.
In their original study on the skeleton, the authors note that the child lived several thousand years after Neanderthals had supposedly disappeared, suggesting that these ancestral traits must have been deeply ingrained within the human genome and that the young boy was therefore “the descendant of extensively admixed populations.” In other words, interbreeding between humans and Neanderthals didn’t just happen once or twice, but occurred on a population level, resulting in significant hybridization.
This, in turn, implies that Neanderthals didn’t simply die out when modern humans came along, but repeatedly hooked up with their new neighbours to the extent that they partially merged with them.
At the time of the discovery, this idea was seen as pretty radical and somewhat shocking, prompting some scholars to refute the original findings. One analysis, for instance, concluded that the Lapedo Child was not a hybrid after all but, was just an oddly-shaped modern human sprog.
However, the admixture theory was finally proven in 2010 when researchers sequenced the Neanderthal genome. In doing so, they revealed that all modern non-African populations contain between 1 and 4 percent Neanderthal DNA, thus confirming that our ancient ancestors did interbreed with these extinct hominids.
Thankfully, our phenotypes have straightened out somewhat over the millennia and we no longer possess the Neanderthal physique. However, like the Lapedo Child, those of us who hail from outside of Africa are all modern human-Neanderthal hybrids.
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現代日本人來源-Emily Cooke
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索引：
Jomon：繩文人
Yayoi people：彌生人
Modern Japanese people arose from 3 ancestral groups, 1 of them unknown, DNA study suggests
Emily Cooke, 04/18/24
Modern Japanese people largely originated from three ancestral groups and carry ancient DNA that may influence their risk of developing certain diseases, genetic analyses suggest.
A large new study has revealed new insight into the evolutionary history of Japanese people. (Image credit: Grant Faint via Getty Images) (請至原網頁參看照片)
Modern Japanese people largely descend from three ancestral groups, a new study suggests. The research also reveals genetic ties with our closest extinct relatives — the Neanderthals and Denisovans — and how these genes may affect present-day disease risk.
In one of the largest non-European analyses of its kind, scientists sequenced the DNA of more than 3,200 Japanese people across seven regions of the country, extending from the snowy mountains of Hokkaido in the north to the subtropical southern shores of Okinawa.
The researchers collated these genetic data, along with relevant clinical information, into a large new database called the Japanese Encyclopedia of Whole-Genome/Exome Sequencing Library (JEWEL).
The team discovered that modern Japanese people mostly descended from three ancestral groups: Neolithic Jomon hunter-gatherers; a group believed to have been the ancient predecessors of the Han Chinese; and an unidentified group with ties to Northeast Asia. This finding further challenges a contested, three-decades-long hypothesis that Japanese people originated from the Jomon people and, later, rice-farming Yayoi migrants from continental Asia.
The new analysis also revealed 42 pieces of DNA that Japanese people inherited from Neanderthals and two from Denisovans that could be linked to complex traits, meaning those that are encoded by multiple genes. This inheritance was likely the result of earlier interbreeding events between these ancient groups and early Homo sapiens, the authors wrote in the paper.
Denisovan-derived DNA within a gene called NKX6-1 was associated with the development of type 2 diabetes (T2D), and within the gene POLR3E, it was tied to height, the authors found. Eleven Neanderthal-derived DNA sequences were found to be associated with seven diseases, including T2D, coronary artery disease, prostate cancer and the inflammatory disorder rheumatoid arthritis. Most of these 44 chunks of ancient DNA are unique to East Asians, the authors said.
Until recently, large-scale genetic sequencing research has focused on analyzing DNA from people of European descent, leaving a significant gap in our understanding of other human populations, including those in Asia. Therefore, the new findings may provide some long-coveted answers.
"This comprehensive genetic dataset enables us to delve into uncharted territories concerning population and medical genetics of the Japanese population," the authors wrote in a paper describing their findings, published Wednesday (April 17) in the journal Science Advances.
These discoveries could even supplement research that could lead to the development of personalized medicine, the authors wrote.
For instance, the team identified gene mutations that could be clinically important within the Japanese population. One notable example is a mutation in a gene called PTPRD that was found in six people in the cohort. Clinical information was available for three of these individuals, who experienced several of the same health conditions, including having heart attacks, kidney failure and high blood pressure.
JEWEL will serve as a "reference for future genetic research within and beyond the Japanese population," the study authors concluded.
Emily Cooke is a health news writer based in London, United Kingdom. She holds a bachelor's degree in biology from Durham University and a master's degree in clinical and therapeutic neuroscience from Oxford University. She has worked in science communication, medical writing and as a local news reporter while undertaking journalism training. In 2018, she was named one of MHP Communications' 30 journalists to watch under 30. (emily.cooke@futurenet.com)
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Ancient bones reveal previously unknown Japanese ancestors
Freckled woman with high alcohol tolerance lived in Japan 3,800 years ago
Analysis of ancient teeth questions theory that Native Americans originated from Japan
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龍人與丹尼索文人同源同種？ - Robin McKie
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根據DNA分析和發現的頭骨，人類學家認為：中國龍人(Homo longi)和丹尼索文斯人很可能同源同種。
Scientists link elusive human group to 150,000-year-old Chinese ‘dragon man’
Researchers have found fresh evidence that may connect the mysterious Denisovans to the early human species Homo longi
Robin McKie, Science editor, 03/30/24
A preliminary portrait of a young woman from the Denisovans, early humans whom scientists know little about. Photograph: Maayan Harel (請至原網頁查看圖片)
They remain one of the most elusive groups of humans to have walked on earth. Evidence from the DNA traces left by Denisovans shows they lived on the Tibetan plateau, probably travelled to the Philippines and Laos in south Asia and might have made their way to northern China more than 100,000 years ago. They also interbred with modern humans.
What Denisovans looked like or how they lived has remained a mystery, however. Only a jaw fragment, a few bits of bone and one or two teeth provide any evidence of their physical characteristics.
Their DNA, which was first found in samples from the Denisova cave in Siberia in 2010, provides most of our information about their existence.
But recently scientists have pinpointed a strong candidate for the species to which the Denisovans might have belonged. This is Homo longi – or “Dragon man” – from Harbin in north-east China. This key fossil is made up of an almost complete skull with a braincase as big as a modern human’s and a flat face with delicate cheekbones. Dating suggests it is at least 150,000 years old.
“We now believe that the Denisovans were members of the Homo longi species,” said Prof Xijun Ni of the Chinese Academy of Sciences in Beijing, last week. “The latter is characterised by a broad nose, thick brow ridges over its eyes and large tooth sockets.”
The possible Denisovan-Homo longi link is one of several recent developments by researchers working on these humans with whom Homo sapiens shared the planet for hundreds of thousands of years. It is even thought they could have played a key role in our own evolution.
A reconstruction of the head of a young woman belonging to the Denisovan group of early humans based on a skeletal profile from DNA. Photograph: Maayan Harel (請至原網頁查看圖片)
Scientists in Tibet have discovered a Denisovan gene in local people, the result of interbreeding between the two species in the distant past. Crucially, this gene has been shown to help modern men and women survive at high altitudes.
In addition, evidence to support the Denisovan-Homo longi link has also been traced to the Tibetan plateau, where scientists began studying a jawbone initially found in a remote cave 3,000 metres (10,000ft) above sea level by a Buddhist monk, who kept it as a relic.
The bone was found not to come from a modern human. But only when researchers began to study the cave where the jawbone had been originally discovered did they find its sediments were rich in Denisovan DNA. In addition, it was found the fossil itself contained proteins that indicated Denisovan origins.
“It was the first time a Denisovan fossil find had been made outside Sibera and that was very important,” said Janet Kelso of the Max Planck Institute of Evolutionary Anthropology in Leipzig, Germany. “Equally intriguing was the fact that the jawbone has teeth that are similar to the teeth found in Homo longi. So I think the evidence suggests a link between the cranium and Denisovans”
This view was backed by Prof Chris Stringer of the Natural History Museum in London. “The evidence supports the idea that Denisovans were members of Homo longi but we are still short of absolute proof. Nevertheless, that will come with time, I believe.”
A big problem for researchers has been the fact that no DNA has yet been found in Chinese fossils such as Homo longi, added Stringer. “Their genes have not survived the passing of time. However, using the techniques of proteomics may provide key new data. These focus on a fossil’s proteins, which survive for far longer than its DNA and could tell us much more about the species.”
Recent research also suggests these people might have played a key role in the evolution of our own species.
The impact of the Denisovan gene found in Tibetans today provides one example. But Denisovan DNA has also been found in other modern populations, including people in New Guinea, northern Australia and the Philippines, and appears to have helped them fight infections from diseases such as malaria.
地圖顯示丹尼索文人種分佈地區 (請至原網頁查看圖片)
Denisovans settled in areas that covered a very varied geography, said Stringer. “Some were hot and low-lying, others were cold and mountainous. They represented very diverse habitats, from the Tibetan plateau to islands like Sulawesi [in Indonesia].”
By contrast, the Neanderthals, the third large grouping of humans that evolved over the past few hundreds of thousands of years, confined themselves to the cooler climates of a region that stretched east from Europe to southern Siberia.
They did not expand from this relatively uniform environment. So is the rich variety of homelands adopted by the Denisovans a sign that they were capable of much more diverse and adaptive behaviour than Neanderthals, scientists are now asking?
Homo sapiens also appears to have interbred with Denisovans on more than one occasion. “Indeed, there is good evidence that some modern humans interbred with genetically distinct Denisovans on multiple occasions,” said Kelso. “This suggests that the two groups coexisted for an extended time, with some studies suggesting a last contact as recently as 25,000 years ago.”
Crucially, by this time, Neanderthals were already extinct.
Research being carried out by Ni and Stringer also suggests that of the three main bands of humans who evolved at this time, Homo sapiens and the Homo longi group were the last to diverge on different evolutionary pathways, possibly a million years ago, with the Neanderthals branching off even earlier.
However, DNA analyses have suggested more recent divergence dates, with Homo sapiens splitting off first, so this is a crucial question for future research, said Stringer.
“How often our paths crossed after that parting of the ways is also now a topic of intense scientific interest,” he added. “We have got so much to learn.”
Related Reading：
Where did they all go? How Homo sapiens became the last human species left
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人類起源於何時？何地？ –--- Gemma Tarlach
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Where Did Humans Evolve? (Probably Not Where You’re Thinking)
For decades, East Africa was considered the birthplace of our species. Fossils from Morocco suggest otherwise.
GEMMA TARLACH, 02/22/24
DRIVE WEST ABOUT TWO HOURS from the vibrant souks of Marrakech and you will reach the small village of Tlet Ighoud. The rural community stretches along the intersection of two narrow, minor highways. If you follow one of them north for a couple miles, you’ll find an old pit from an abandoned mining operation.
In this arid region, the site’s tumble of red and orange rocks seems like nothing special, but it was here, more than 60 years ago, that miners uncovered what appeared to be a human skull. The find was the first of many from the site known as Jebel Irhoud. Collectively, the discoveries there have shaken up the story of our species, by challenging two of the most fundamental questions we can ask: When did we evolve and where did we come from?
For decades, those questions have been answered based on bones. But all of the early Homo sapiens fossils known to science could comfortably fit in your living room with space to spare. Most come from East African sites, such as northern Tanzania’s Ngaloba beds, or Omo Kibish, a collection of locations nestled in a remote Ethiopian river valley. Fossils from both of those locales, and others in East Africa, have been dated to between 120,000 and 200,000 years ago, and long represented what scientists thought was the earliest chapter in the story of H. sapiens. (In 2022, using a more refined dating method, researchers discovered that Omo I, a skull from Omo Kibish, is around 233,000 years old.) Working with that fossil evidence, it made sense to think that we had evolved in East Africa. After all, the region had also been home to several earlier members of our family tree, including celebrity fossil Lucy (the most famous example of Australopithecus afarensis, which lived around three million years ago).
The first skull fossil from Jebel Irhoud, found by a miner in the early 1960s, was initially thought to belong to a Neanderthal. RYAN SOMMA, CC BY-SA 2.0/WIKIMEDIA (請至原網頁觀看相關照片)
When miners unearthed that first skull from Jebel Irhoud in 1961, it was assumed to belong to a Neanderthal—modern humans’ closest evolutionary relative, H. neanderthalensis—who had lived some 40,000 years ago. Subsequent analysis suggested it was actually H. sapiens, and pushed the age of the skull back to about 160,000 years—much earlier in the human story, but still younger than several of the fossils found in East Africa. Our species evolved to walk and run long distances, so it would be no great feat for early humans to spread across Africa in the millennia after our birth in the east.
Then, in the early years of the 21st century, a new team of paleoanthropologists arrived at Jebel Irhoud. They picked over spots that had been chewed up by the mining operation, where the first fossils were found, but also began excavating new and previously undisturbed areas. They went back further in time as they dug. There, in those older layers of rock, they found additional skulls, other human bones, stone tools, and ribs of zebras and gazelles that show clear evidence of having been butchered for food.
Later came the biggest news of all: Using multiple methods, the team determined the finds were about 300,000 years old. The Jebel Irhoud fossils, which include skulls with distinctively modern human faces, were tens of thousands of years older than any human fossil found in East Africa.
The discovery, published in a series of papers and reactions in Nature in 2017, made headlines—and created controversy. Critics noted that while the facial features of the Jebel Irhoud skulls were remarkably modern, the overall shape of the skulls was longer and lower than the bubble-like, rounded braincase of modern humans. That difference, they argued, made a case that the Jebel Irhoud individuals were actually not H. sapiens, but might belong to an earlier species, such as H. antecessor, which lived about a million years ago in Spain.
A reconstruction of an early Homo sapiens skull from Jebel Irhoud shows strikingly modern facial features, but a braincase (in blue) that is less bubble-like than the rounded skull of our species today. PHILIPP GUNZ, CC-BY-SA 2.0/MPI EVA LEIPZIG (請至原網頁觀看相關照片)
The team behind the 2017 findings, led by paleoanthropologists from Germany’s Max Planck Institute for Evolutionary Anthropology, remained steadfast in their assessment of the Jebel Irhoud fossils as H. sapiens. But they were also the first to caution that Morocco should not be considered the birthplace of our species.
There are, after all, a few other very early fossils, such as a skull from Florisbad, South Africa, that is at least 260,000 years old. That skull resembles the Jebel Irhoud examples, found on the opposite side of the continent, and is also considered by some paleoanthropologists to belong to early H. sapiens. The only way both the Florisbad and Jebel Irhoud individuals could belong to our species is if humans evolved much earlier than we thought, which could put our true birthplace anywhere on the continent.
While exactly where and how the Jebel Irhoud humans fit into our origin story remains uncertain, their fossils have fueled a shift in how we view human evolution. Since 2017, more paleoanthropologists have moved away from the idea that we evolved fully in East Africa and then dispersed across the continent and beyond.
Today, more researchers embrace a Pan-African idea of human evolution, which hypothesizes that our species evolved across a wide geographic area as multiple populations mixed and mingled. That theory got a boost in 2023, when genomic research published in Nature concluded that humans evolved from two ancestral populations that occasionally interbred over hundreds of thousands of years.
It was beyond the scope of that 2023 paper to determine the geographic range of these ancestral populations, but the role geography plays in forming our ideas about human evolution is often overlooked. There are many regions of Africa where highly acidic soil or other environmental conditions make fossilization almost impossible — bones there break down before they can be preserved, erasing any evidence of our ancestors. In other areas, notably East Africa, paleoanthropologists have found early human fossils because, frankly, that’s where they went looking for them. (It’s a similar story in South Africa, home to several important fossils of multiple early human relatives and the boldly named Cradle of Humankind, which stakes the country’s claim, over East Africa, as our first home.)
But back to your living room, the one theoretically filled with every early H. sapiens fossil ever found: That’s still all we have from our earliest chapters. Interpreting them is like trying to read a version of Darwin’s On the Origin of Species that’s been printed without any vowels—or most of the consonants, for that matter. Understanding the true map and timeline of human evolution will require finding and analyzing many, many more fossils, and as well as the clues tucked into DNA from both living and ancient populations. We may never know exactly where and when the first human was born, but with every fossil found, the likeliest spot shifts in both time and place. The next big shift may be only one strike of a miner’s pickaxe away.
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歐洲人類史新發現 2 -- Ellyn Lapointe
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下文所報導的研究論文與《歐洲人類史新發現 1》一文相同(本欄02/04/24)；但兩者重點略有差異。現代人類祖先曾與林德索人比鄰而居甚至交媾，數年前已經由基因學領域的研究證實。此研究則從考古人類學領域以實體物件做為證據。
兩文可與《石器文化演進新理論》參看(本欄02/10/24)。
Human bones unearthed from a German cave have altered the timeline of ancient human history
Ellyn Lapointe, 02/13/24
* Human bones in a German cave place Homo Sapiens in Europe 7,500 years earlier than experts thought.
* The findings suggest Homo sapiens lived near Neanderthals for millennia, which is a new revelation.
* Previously, scientists thought Homo sapiens arrived right around the time Neanderthals went extinct.
For years, archaeologists have argued over an ancient culture with the unwieldy title: the Lincombian-Ranisian-Jerzmanowician technocomplex. Even scientists know that’s a mouthful, so they call it the LRJ for short.
The LRJ is characterized by the creation of specific blades and leaf points, which share aspects of both Neanderthal and Homo sapien craftsmanship.
LRJ stone tools newly excavated from Ranis. Josephine Schubert / Museum Burg Ranis (請至原網頁查看圖片)
The debate is over who made them, and the answer could help offer clues as to what happened about 45,000 years ago — when Neanderthals, one of our closest human relatives, mysteriously went extinct across Europe while Homo sapiens, ultimately, thrived.
“The usual wisdom was to consider that they were made most likely by late Neanderthals,” said study co-author Jean-Jacques Hublin, a professor of paleoanthropology at the College of France.
But Hublin and his colleagues wanted to settle the debate once and for all.
This led them to Ilsenhöhle cave in Ranis, Germany, one of several sites across Northwestern Europe where LRJ artifacts have been found.
The opening of Ilsenhöhle cave in Ranis, Germany. Tim Schüler / TLDA (請至原網頁查看圖片)
Besides solving the mystery they sought, the researchers wound up discovering so much more.
Mining ancient DNA
When they excavated the cave, the researchers uncovered more than just LRJ artifacts — they came upon tiny bone fragments, too.
Most of the bones were too small to identify what animal they came from based on looks, alone.
But thanks to a revelatory new analysis called zooarchaeology by mass spectrometry, or ZooMS, the researchers were able to determine that 13 of the roughly 2,000 bone fragments they analyzed belonged to early humans.
The researchers analyzed animal teeth found at Ranis to gain insight into the climate these animals lived in. Max Planck Institute for Evolutionary Anthropology (請至原網頁查看圖片)
The next step was determining which species of ancient human they were from. If the team could figure that out, then it would likely point them to who made the LRJ artifacts in the cave, thus solving the mystery, Hublin said.
To that end, they extracted DNA, which confirmed the bones belong to Homo sapiens, providing strong evidence that they were responsible for the LRJ artifacts. “Voila!” Hublin said triumphantly.
But they weren’t done, yet.
The researchers extracted protein from the bone fragments to analyze their DNA. Dorothea Mylopotamitaki (請至原網頁查看圖片)
The team also used radiocarbon dating to date the bones, and were surprised by what they discovered.
According to their data, Homo sapiens were present in Ranis 47,500 years ago — thousands of years earlier than previously thought.
Unlikely neighbors
Until this discovery, archaeologists believed Homo sapiens did not arrive in Western Europe until 42,000 years ago, contributing to the extinction of Neanderthals.
To get to the LRJ layer, archeologists had into an 8-meter-deep shaft below Ranis. Marcel Weiss (請至原網頁查看圖片)
A growing library of evidence has been pushing this timeline back more and more. Hublin and the team's discoveries are the latest series of studies adding to the mounting pile.
The research was published in three papers in the peer-reviewed journals Nature and Nature Ecology and Evolution and paints a very different picture of history.
It suggests there were small “pioneer” groups of Homo sapiens living in Europe with Neanderthals for thousands of years before the species went extinct.
Whether these two groups ever interacted during that time remains unclear.
“It’s not at all the picture we had years ago of this wave of Homo sapiens moving into Europe and replacing the Neanderthals,” said Hublin. “What we see now is that it was not a wave, it was several wavelets,”
Moreover, the research suggests these early Homo sapien “pioneers” were more hardcore than we’ve given them credit for.
Hardcore humans
Previous research asserted that Homo sapiens were only able to enter Europe during warmer time periods because they were adapted to the warm climate of Africa, where they originated from.
But the specimens and artifacts found at Ranis suggest they actually entered directly through the chilly Northwest, and that this region was much colder than previously thought.
Analysis of animal teeth collected at the site revealed the climate was 7 to 15 degrees Celsius colder than it is today, similar to that of northern Scandinavia or parts of Siberia, said Hublin.
Additionally, analysis of animal remains revealed that mammals adapted to extreme cold were present at Ranis, including wooly mammoths, reindeer, and wolverines.
Analysis of over 1,000 animal bones from Ranis showed that early Homo sapiens processed the carcasses of deer but also of carnivores, including wolves. Geoff M. Smith (請至原網頁查看圖片)
Questions remain about how warm-weather-adapted Homo sapiens survived such a dramatic transition. But they likely made warm clothing out of furs from these animals, explains study co-author Geoff Smith, a zooarchaeologist at the University of Kent.
Rewriting prehistory
Together, these findings paint a picture of human prehistory that is very different from the one we had before. But there are still questions to be answered.
The researchers have no plans to excavate Ranis further, and the cave has been closed off for safety reasons. But they will continue to study the specimens and artifacts from this last dig to dive deeper into interactions between Homo sapiens and Neanderthals during this time.
“I think we have more to discover,” Hublin said. “What’s ahead of us is understanding what was going on among the late Neanderthals. To what extent have they been penetrated by these newcomers? What kind of interactions do they have with them? But I think it’s a great step to have resolved the LRJ story.”
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石器文化演進新理論-Mirjam Guesgen
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索引：
flint：燧石；燧石由于堅硬，破碎後產生鋒利的斷口，所以是最早為石器時代的原始人所青睞。
Neolithic：新石器時代
Epipaleolithic period：中石器時代；refer to the geographic areas of Levant and, often, the rest of the Near East
Mesolithic：中石器時代；refer to the geographic areas of parts of Southeast Europe
Paleolithic Period：舊石器時代
Lower Paleolithic period：舊石器時代早期
Middle Paleolithic period：舊石器時代中期
Upper Paleolithic period：舊石器時代晚期
A Prehistoric Tool Discovery May Have Just Rewritten Human History
New research suggests a sudden "revolution" in human history that allowed our species to thrive and spread was a longer and more complex process.
Mirjam Guesgen, 02/09/24
Somewhere between 50-40,000 years ago, anatomically modern humans overtook Neanderthals and other archaic humans, spreading out all over Eurasia.
That shift has mostly been attributed to a dramatic and sudden "revolution" called the Middle-Upper Paleolithic cultural transition, where modern humans improved their tool-making, found new and different sources of food, took to the seas, and expressed themselves through ornaments and cave art. Now, a study published Wednesday in Nature Communications has challenged this narrative, instead implying that this “revolution” was more of a gradual and complex process.
Researchers came to this conclusion by analyzing how productive ancient humans were when it came to turning rocks into tools during a 50,000-year span between the Late Middle Paleolithic (69,000 years ago), through the Upper Paleolithic, to the Epipaleolithic period (15,000 years ago). The tools came from five sites across the western Hisma Basin in southern Jordan.
Specifically, researchers quantified the ratio between the length of a particular stone tool’s cutting edge with the mass of the stone as a whole. The more cutting-edge length per mass of stone, the more efficiently early humans used the raw stone material. “Stone raw material, like flint, is not everywhere. It needs to be procured from certain sources,” the study’s lead author, Seiji Kadowaki from Nagoya University in Japan, told Motherboard in an email. “So, more economical consumption of stone raw material reduces the cost for the procurement of raw material.”
Kadowaki said they chose this metric because they needed a way to compare very different types of stone tools in a systematic way. “Because stone tool forms and their production technology changed and varied from the Middle Paleolithic to the Upper Paleolithic, the classification system for stone tools differs between the two periods. Thus, it is difficult to have consistent criteria for comparison of the two periods,” he told Motherboard in an email.
He and his colleagues noticed that modern humans became more productive not before or at the beginning of the Middle-Upper Paleolithic cultural transition, but after they’d already started to spread out into new geographical areas in the Early Upper Paleolithic. “In terms of the productivity of cutting-edge length, its development does not simply coincide with the timing of the dispersal of modern humans.”
Much of this shift came down to the stones humans used to make tools becoming smaller and lighter. This was probably because around the same time, humans started developing bladelets—small, long, symmetrical stone tools probably used as spear- or arrowheads.
These technological changes came with a shift from humans being more mobile hunter-gatherers to having slightly more stable base camps. Many of the sites researchers looked at were small, with a few hearths—typical for more wandering groups. Some however were “more intensive occupations” where people would stay for longer periods of time. Under this new system, people may have carried around smaller, more portable blades or partially-made ones that they could use to cut up food stored at these base camps.
The latest findings agree with other studies that have been published in recent years, which also argue that the so-called revolution was actually a slower, multi-step process.
Although the latest study is specific to archeological finds in Jordan, the authors say it serves as a working hypothesis for other places worldwide, including Europe and Central-North Asia where archeologists have seen similar patterns in tool evolution.
Kadowaki also says they need more evidence from other sources before they can definitively paint a new picture of how stone tools evolved. “We need to look at other aspects of stone tools as well as other archaeological records to better understand the technological behaviors and their development at the Middle-Upper Paleolithic transition.”
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歐洲人類史新發現 1 -- Katie Hunt
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Bones found in 8-meter-deep pit may ‘fundamentally change’ history of humans in Europe
Katie Hunt, CNN, 02/02/24
Microscopic fragments of protein and DNA recovered from bones discovered in 8-meter-deep cave dirt have revealed Neanderthals and humans likely lived alongside one another in northern Europe as far back as 45,000 years ago.
The genetic analysis of the fossils, which were found in a cave near the town of Ranis in eastern Germany, suggested that modern humans were the makers of distinctive, leaf-shaped stone tools that archaeologists once believed were crafted by Neanderthals, the heavily built hominins who lived in Europe until about 40,000 years ago.
Modern humans, or homo sapiens, weren’t previously known to have lived as far north as the region where the tools were made.
“The Ranis cave site provides evidence for the first dispersal of Homo sapiens across the higher latitudes of Europe. It turns out that stone artifacts that were thought to be produced by Neanderthals were, in fact, part of the early Homo sapiens toolkit,” said research author Jean-Jacques Hublin, a professor at the Collège de France in Paris and emeritus director at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, in a news release.
“This fundamentally changes our previous knowledge about the period: Homo sapiens reached northwestern Europe long before Neanderthal disappearance in southwestern Europe.”
The discovery means the two groups, who once interbred and left most humans alive today with traces of Neanderthal DNA, may have overlapped for several thousand years. It also shows that Homo sapiens, our species, crossed the Alps into the cold climes of northern and central Europe earlier than thought.
Three studies detailing the discoveries and lab analysis were published Wednesday in the journals Nature and Nature Ecology & Evolution.
Earliest Homo sapiens fossils found north of the Alps
The style of stone tool found at Ranis has also been discovered elsewhere across Europe, from Moravia and eastern Poland to the British Isles, according to the studies. Archaeologists call the tool style Lincombian-Ranisian-Jerzmanowician, or LRJ, in reference to the places where it was first identified.
To identify who made the artifacts, the team excavated Ilsenhöhle cave near Ranis from 2016 to 2022. When the cave was first excavated in the 1930s, only the tools were found and analyzed. This time around the team was able to dig deeper and more systematically, ultimately uncovering human fossils there for the first time.
“The challenge was to excavate the full 8-metre sequence from top to bottom, hoping that some deposits were left from the 1930s excavation,” said study coauthor Marcel Weiss, a researcher at Friedrich-Alexander University Erlangen-Nürnberg and the Max Planck Institute for Evolutionary Anthropology, in a statement. “We were fortunate to find a 1.7 metre thick rock the previous excavators did not get past. After removing that rock by hand, we finally uncovered the LRJ layers and even found human fossils.”
However, the human remains weren’t immediately identifiable among the hundreds of bone fragments unearthed during the six-year dig. It was only later the team knew definitively that the layers of sediment that contained the LRJ stone tools also included humans remains.
The researchers used proteins extracted from bone fragments to identify animal and human remains they found, a technique known as palaeoproteomics. It allows scientists to identify human and animal bones when their form is unclear or uncertain. Using the same technique, the team also managed to identify human remains among bones excavated during the 1930s.
However, the protein analysis was only able to identify the bones as belonging to hominins — a category that includes Homo sapiens and Homo neanderthalensis, or Neanderthals. To distinguish between the two, the team was able to extract fragments of ancient DNA from the 13 human fossils they identified.
“We confirmed that the skeletal fragments belonged to Homo sapiens,” said study coauthor Elena Zavala, a postdoctoral research fellow at the University of California, Berkeley, and Max Planck Institute for Evolutionary Anthropology, in the release.
“Interestingly, several fragments shared the same mitochondrial DNA sequences — even fragments from different excavations,” Zavala added. “This indicates that the fragments belonged to the same individual or were maternal relatives, linking these new finds with the ones from decades ago.”
Unexpected adaptability
Radiocarbon dating of the fossils and other artifacts in the cave suggested that these early humans were living there from around 45,000 years ago, making them the earliest Homo sapiens known to have inhabited northwestern Europe.
The region would have had a dramatically different climate then, with conditions typical of steppe tundra such as that found in present-day Siberia. The dig revealed the presence of reindeer, cave bears, woolly rhinoceroses and horses. The researchers also concluded that hibernating cave bears and denning hyenas primarily used the cave, which had only periodic human presence.
“This shows that even these earlier groups of Homo sapiens dispersing across Eurasia already had some capacity to adapt to such harsh climatic conditions,” said coauthor Sarah Pederzani, a postdoctoral fellow at the University of La Laguna in Spain, who led the paleoclimate study of the site. “Until recently, it was thought that resilience to cold-climate conditions did not appear until several thousand years later, so this is a fascinating and surprising result,” she said, according to the news release.
William E. Banks, a researcher at the University of Bordeaux in France, said the studies showed how new methods are allowing archaeologists to examine sites in unprecedented detail, improving the ability to pinpoint when a site was occupied.
The “discoveries provide another important piece of the puzzle of this culturally and demographically complex period in Europe,” Banks noted in a commentary published alongside the studies. However, Banks, who wasn’t involved in the research, added that archaeologists “must be careful not to generalize findings from one or two sites.”
He noted that recent discoveries suggested Neanderthals were more culturally and cognitively complex than popular stereotypes suggest and that archaeologists should “not necessarily assume” in all cases that modern humans made more complex styles of stone tools from that pivotal period before Neanderthals disappeared.
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