Neandertals went underwater to collect clam shells and pumice for their tools
Neandertals went underwater for their tools
Neandertals collected clam shells and pumice from coastal waters to use as tools
Neandertals collected clam shells and volcanic rock from the beach and coastal waters of Italy during the Middle Paleolithic, according to a study published January 15, 2020 in the open-access journal PLOS ONE by Paola Villa of the University of Colorado and colleagues.
Neandertals are known to have used tools, but the extent to which they were able to exploit coastal resources has been questioned. In this study, Villa and colleagues explored artifacts from the Neandertal archaeological cave site of Grotta dei Moscerini in Italy, one of two Neandertal sites in the country with an abundance of hand-modified clam shells, dating back to around 100,000 years ago.
The authors examined 171 modified shells, most of which had be retouched to be used as scrapers. All of these shells belonged to the Mediterranean smooth clam species Callista chione. Based on the state of preservation of the shells, including shell damage and encrustation on the shells by marine organisms, the authors inferred that nearly a quarter of the shells had been collected underwater from the sea floor, as live animals, as opposed to being washed up on the beach. In the same cave sediments, the authors also found abundant pumice stones likely used as abrading tools, which apparently drifted via sea currents from erupting volcanoes in the Gulf of Naples (70km south) onto the Moscerini beach, where they were collected by Neandertals.
These findings join a growing list of evidence that Neandertals in Western Europe were in the practice of wading or diving into coastal waters to collect resources long before Homo sapiens brought these habits to the region. The authors also note that shell tools were abundant in sediment layers that had few stone tools, suggesting Neandertals might have turned to making shell tools during times where more typical stone materials were scarce (though it's also possible that clam shells were used because they have a thin and sharp cutting edge, which can be maintained through re-sharpening, unlike flint tools).
The authors add: "The cave opens on a beach. It has a large assemblage of 171 tools made on shells collected on the beach or gathered directly from the sea floor as live animals by skin diving Neandertals. Skin diving for shells or fresh water fishing in low waters was a common activity of Neandertals, according to data from other sites and from an anatomical study published by E. Trinkaus. Neandertals also collected pumices erupted from volcanoes in the gulf of Naples and transported by sea to the beach."
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Citation: Villa P, Soriano S, Pollarolo L, Smriglio C, Gaeta M, D'Orazio M, et al. (2020) Neandertals on the beach: Use of marine resources at Grotta dei Moscerini (Latium, Italy). PLoS ONE 15(1): e0226690. https:/
Funding: National Science Foundation Grant 1118143, BCS Archaeology, to PV (PI) and SS (co-PI). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.
Press release from the Public Library of Science
Beach-combing Neanderthals dove for shells
Did Neanderthals wear swimsuits? Probably not. But a new study suggests that some of these ancient humans might have spent a lot of time at the beach. They may even have dived into the cool waters of the Mediterranean Sea to gather clam shells.
The findings come from Grotta dei Moscerini, a picturesque cave that sits just 10 feet above a beach in what is today the Latium region of central Italy.
In 1949, archaeologists working at the site dug up some unusual artifacts: dozens of seashells that Neanderthals had picked up, then shaped into sharp tools roughly 90,000 years ago.
Now, a team led by Paola Villa of the University of Colorado Boulder has uncovered new secrets from those decades-old discoveries. In research published today (editor's note: January 15) in the journal PLOS ONE, she and her colleagues report that the Neanderthals didn't just collect shells that were lying out on the beach. They may have actually held their breath and went diving for the perfect shells to meet their needs.
Villa, an adjoint curator in the CU Museum of Natural History, said the results show that Neanderthals may have had a much closer connection to the sea than many scientists thought.
"The fact they were exploiting marine resources was something that was known," Villa said. "But until recently, no one really paid much attention to it."
Cave discoveries
When archaeologists first found shell tools in Grotta dei Moscerini, it came as a surprise. While Neanderthals are well-known for crafting spear tips out of stone, few examples exist of them turning shells into tools.
But the find wasn't a fluke. The 1949 excavation of the cave unearthed 171 such tools, all valves from shell belonging to a local species of mollusk called the smooth clam (Callista chione). Villa explained that the ancient humans used stone hammers to chip away at these shells, forming cutting edges that would have stayed thin and sharp for a long time.
"No matter how many times you retouch a clam shell, its cutting edge will remain very thin and sharp," she said.
But did the Neanderthals, like many beachgoers today, simply collect these shells while taking a stroll along the sand?
To find out, Villa and her colleagues took a closer look at those tools. In the process, they found something they weren't expecting. Nearly three-quarters of the Moscerini shell tools had opaque and slightly abraded exteriors, as if they had been sanded down over time. That's what you'd expect to see, Villa said, on shells that had washed up on a sandy beach.
The rest of the shells had a shiny, smooth exterior.
Those shells, which also tended to be a little bit bigger, had to have been plucked directly from the seafloor as live animals.
"It's quite possible that the Neanderthals were collecting shells as far down as 2 to 4 meters," Villa said. "Of course, they did not have scuba equipment."
Researchers also turned up a large number of pumice stones from the cave that Neanderthals had collected and may have used as abrading tools. The stones, Villa and her colleagues determined, washed onto the Moscerini beach from volcanic eruptions that occurred more than 40 miles to the south.
Going for a dip
She's not alone in painting a picture of beach-loving Neanderthals.
In an earlier study, for example, a team led by anthropologist Erik Trinkaus identified bony growths on the ears of a few Neanderthal skeletons. These features, called "swimmer's ear," can be found in people who practice aquatic sports today.
For Villa, the findings are yet more proof that Neanderthals were just as flexible and creative as their human relatives when it came to eking out a living--a strong contrast to their representation in popular culture as a crude cavemen who lived by hunting or scavenging mammoths.
"People are beginning to understand that Neanderthals didn't just hunt large mammals," Villa said. "They also did things like freshwater fishing and even skin diving."
Other coauthors on the new study included researchers from the French National Centre for Scientific Research, the University of Geneva, Roma Tre University, Sapienza University of Rome and the University of Pisa.
Press release from the University of Colorado at Boulder
A warrior on a unique Bronze Age battlefield site in the Tollense Valley
Lost in Combat? Researchers discover belongings of a warrior on unique Bronze Age battlefield site
Recent archaeological investigations in the Tollense Valley led by the University of Göttingen, the State Agency for Cultural Heritage in Mecklenburg-Vorpommern and the University of Greifswald have unearthed a collection of 31 unusual objects. Researchers believe this is the personal equipment of a Bronze Age warrior who died on the battlefield 3,300 years ago. This unique find was discovered by a diving team headed by Dr Joachim Krüger, from the University of Greifswald, and seems to have been protected in the river from the looting, which inevitably followed fighting. The study was published in Antiquity.
The archaeological records of the European Bronze Age are dominated by settlement finds, hoards and evidence of funeral sites. However, the site at the river Tollense in Northern Germany is very different and provides for the first time in Europe the evidence of a prehistoric battlefield. Over 12,000 pieces of human bone have already been recovered from the valley and osteoanthropologist Ute Brinker, from the State Agency has identified more than 140 individuals – young adult males in good physical condition. Their bones showed signs of recent trauma – the result of close and long-range weapons – and healed lesions, which probably indicate they were accustomed to combat. Isotopic results suggested that at least some of the group were not from the local area, but until now, it was not clear how far they travelled.
The discovery of a new set of artefacts from the remains of battle provides important new clues. The divers could document a number of Bronze finds in their original position on the river ground, among them a decorated belt box, three dress pins and also arrow heads. Surprisingly they also found 31 objects (250g) tightly packed together, suggesting they were in a container made of wood or cloth that has since rotted away. The items include a bronze tool with a birch handle, a knife, a chisel and fragments of bronze. Radiocarbon dating of the collection of objects demonstrates that the finds belong to the battlefield layer and they were probably the personal equipment of one of the victims. The finds were studied in a Master’s thesis by Tobias Uhlig and the new results make it increasingly clear that there was a massive violent conflict in the older Nordic Bronze Age (2000–1200 BC). In fact, recent evidence suggests that it is likely to have been on a large scale, clearly stretching beyond regional borders.
Professor Thomas Terberger, from the Department of Pre- and Early History at the University of Göttingen, says, “This is the first discovery of personal belongings on a battlefield and it provides insights into the equipment of a warrior. The fragmented bronze was probably used as a form of early currency. The discovery of a new set of artefacts also provides us with clues about the origins of the men who fought in this battle and there is increasing evidence that at least some of the warriors originated in southern Central Europe.”
Original publication: Tobias Uhlig et al. Lost in combat? A scrap metal find from the Bronze Age battlefield site at Tollense (2019), Antiquity. DOI: 10.15184/aqy.2019.137
Press release (No. 207 - 15.10.2019) from the University of Göttingen / DE
A Stone Age boat building site has been discovered underwater
A Stone Age boat building site has been discovered underwater
The Maritime Archaeological Trust has discovered a new 8,000 year old structure next to what is believed to be the oldest boat building site in the world on the Isle of Wight.
Director of the Maritime Archaeological Trust, Garry Momber, said "This new discovery is particularly important as the wooden platform is part of a site that doubles the amount of worked wood found in the UK from a period that lasted 5,500 years."
The site lies east of Yarmouth, and the new platform is the most intact, wooden Middle Stone Age structure ever found in the UK. The site is now 11 meters below sea level and during the period there was human activity on the site, it was dry land with lush vegetation. Importantly, it was at a time before the North Sea was fully formed and the Isle of Wight was still connected to mainland Europe.
The site was first discovered in 2005 and contains an arrangement of trimmed timbers that could be platforms, walkways or collapsed structures. However, these were difficult to interpret until the Maritime Archaeological Trust used state of the art photogrammetry techniques to record the remains. During the late spring the new structure was spotted eroding from within the drowned forest. The first task was to create a 3D digital model of the landscape so it could be experienced by non-divers. It was then excavated by the Maritime Archaeological Trust during the summer and has revealed a cohesive platform consisting of split timbers, several layers thick, resting on horizontally laid round-wood foundations.
Garry continued "The site contains a wealth of evidence for technological skills that were not thought to have been developed for a further couple of thousand years, such as advanced wood working. This site shows the value of marine archaeology for understanding the development of civilisation.
Yet, being underwater, there are no regulations that can protect it. Therefore, it is down to our charity, with the help of our donors, to save it before it is lost forever."
The Maritime Archaeological Trust is working with the National Oceanography Centre (NOC) to record and study, reconstruct and display the collection of timbers. Many of the wooden artefacts are being stored in the British Ocean Sediment Core Research facility (BOSCORF), operated by the National Oceanography Centre.
As with sediment cores, ancient wood will degrade more quickly if it is not kept in a dark, wet and cold setting. While being kept cold, dark and wet, the aim is to remove salt from within wood cells of the timber, allowing it to be analysed and recorded. This is important because archaeological information, such as cut marks or engravings, are most often found on the surface of the wood and are lost quickly when timber degrades. Once the timbers have been recorded and have desalinated, the wood can be conserved for display.
Dr Suzanne Maclachlan, the curator at BOSCORF, said "It has been really exciting for us to assist the Trust's work with such unique and historically important artefacts. This is a great example of how the BOSCORF repository is able to support the delivery of a wide range of marine science."
When diving on the submerged landscape Dan Snow, the history broadcaster and host of History Hit, one of the world's biggest history podcasts, commented that he was both awestruck by the incredible remains and shocked by the rate of erosion.
This material, coupled with advanced wood working skills and finely crafted tools suggests a European, Neolithic (New Stone Age) influence. The problem is that it is all being lost. As the Solent evolves, sections of the ancient land surface are being eroded by up to half a metre per year and the archaeological evidence is disappearing.
Research in 2019 was funded by the Scorpion Trust, the Butley Research Group, the Edward Fort Foundation and the Maritime Archaeology Trust. Work was conducted with the help of volunteers and many individuals who gave their time and often money, to ensure the material was recovered successfully.
Press release from National Oceanography Centre
Bird three times larger than ostrich discovered in Crimean cave
Bird three times larger than ostrich discovered in Crimean cave
First evidence that giant ostrich-like birds once roamed Europe
A surprise discovery in a Crimean cave suggests that early Europeans lived alongside some of the largest ever known birds, according to new research published in the Journal of Vertebrate Paleontology.
It was previously thought that such gigantism in birds only ever existed on the islands of Madagascar and New Zealand as well as Australia. The newly-discovered specimen, discovered in the Taurida Cave on the northern coast of the Black Sea, suggests a bird as giant as the Madagascan elephant bird or New Zealand moa. It may have been a source of meat, bones, feathers and eggshell for early humans.
"When I first felt the weight of the bird whose thigh bone I was holding in my hand, I thought it must be a Malagasy elephant bird fossil because no birds of this size have ever been reported from Europe. However, the structure of the bone unexpectedly told a different story," says lead author Dr Nikita Zelenkov from the Russian Academy of Sciences.
"We don't have enough data yet to say whether it was most closely related to ostriches or to other birds, but we estimate it weighed about 450kg. This formidable weight is nearly double the largest moa, three times the largest living bird, the common ostrich, and nearly as much as an adult polar bear."
It is the first time a bird of such size has been reported from anywhere in the northern hemisphere. Although the species was previously known, no one ever tried to calculate the size of this animal. The flightless bird, attributed to the species Pachystruthio dmanisensis, was probably at least 3.5 metres tall and would have towered above early humans. It may have been flightless but it was also fast.
While elephant birds were hampered by their great size when it came to speed, the femur of the current bird was relatively long and slim, suggesting it was a better runner. The femur is comparable to modern ostriches as well as smaller species of moa and terror birds. Speed may have been essential to the bird's survival. Alongside its bones, palaeontologists found fossils of highly-specialised, massive carnivores from the Ice Age. They included giant cheetah, giant hyenas and sabre-toothed cats, which were able to prey on mammoths.
Other fossils discovered alongside the specimen, such as bison, help date it to 1.5 to 2 million years ago. A similar range of fossils was discovered at an archaeological site in the town of Dmanisi in Georgia, the oldest hominin site outside Africa. Although previously neglected by science, this suggests the giant bird may have been typical of the animals found at the time when the first hominins arrived in Europe. The authors suggest it reached the Black Sea region via the Southern Caucasus and Turkey.
The body mass of the bird was reconstructed using calculations from several formulae, based on measurements from the femur bone. Applying these formulae, the body mass of the bird was estimated to be around 450kg. Such gigantism may have originally evolved in response to the environment, which was increasingly arid as the Pleistocene epoch approached. Animals with a larger body mass have lower metabolic demands and can therefore make use of less nutritious food growing in open steppes.
"The Taurida cave network was only discovered last summer when a new motorway was being built. Last year, mammoth remains were unearthed and there may be much more to that the site will teach us about Europe's distant past," says Zelenkov.
Neanderthals used resin 'glue' to craft their stone tools
Neanderthals used resin 'glue' to craft their stone tools
Archaeologists working in two Italian caves have discovered some of the earliest known examples of ancient humans using an adhesive on their stone tools--an important technological advance called "hafting."
The new study, which included CU Boulder's Paola Villa, shows that Neanderthals living in Europe from about 55 to 40 thousand years ago traveled away from their caves to collect resin from pine trees. They then used that sticky substance to glue stone tools to handles made out of wood or bone.
The findings add to a growing body of evidence that suggests that these cousins of Homo sapiens were more clever than some have made them out to be.
"We continue to find evidence that the Neanderthals were not inferior primitives but were quite capable of doing things that have traditionally only been attributed to modern humans," said Villa, corresponding author of the new study and an adjoint curator at the CU Museum of Natural History.
That insight, she added, came from a chance discovery from Grotta del Fossellone and Grotta di Sant'Agostino, a pair of caves near the beaches of what is now Italy's west coast.
Those caves were home to Neanderthals who lived in Europe during the Middle Paleolithic period, thousands of years before Homo sapiens set foot on the continent. Archaeologists have uncovered more than 1,000 stone tools from the two sites, including pieces of flint that measured not much more than an inch or two from end to end.
In a recent study of the tools, Villa and her colleagues noticed a strange residue on just a handful of the flints--bits of what appeared to be organic material.
"Sometimes that material is just inorganic sediment, and sometimes it's the traces of the adhesive used to keep the tool in its socket" Villa said.
Warm fires
To find out, study lead author Ilaria Degano at the University of Pisa conducted a chemical analysis of 10 flints using a technique called gas chromatography/mass spectrometry. The tests showed that the stone tools had been coated with resin from local pine trees. In one case, that resin had also been mixed with beeswax.
Villa explained that the Italian Neanderthals didn't just resort to their bare hands to use stone tools. In at least some cases, they also attached those tools to handles to give them better purchase as they sharpened wooden spears or performed other tasks like butchering or scraping leather.
"You need stone tools to cut branches off of trees and make them into a point," Villa said.
The find isn't the oldest known example of hafting by Neanderthals in Europe--two flakes discovered in the Campitello Quarry in central Italy predate it. But it does suggest that this technique was more common than previously believed.
The existence of hafting also provides more evidence that Neanderthals, like their smaller human relatives, were able to build a fire whenever they wanted one, Villa said--something that scientists have long debated. She said that pine resin dries when exposed to air. As a result, Neanderthals needed to warm it over a small fired to make an effective glue.
"This is one of several proofs that strongly indicate that Neanderthals were capable of making fire whenever they needed it," Villa said.
In other words, enjoying the glow of a warm campfire isn't just for Homo sapiens.
Other coauthors on the study included researchers at Paris Nanterre University in France, University of the Witwatersrand in South Africa, University of Wollongong in Australia, Max Planck Institute for the Science of Human History in Germany, Istituto Italiano di Paleontologia Umana and the University of Pisa.
The research was funded by a National Science Foundation grant to Paola Villa and Sylvain Soriano.
Press release from the University of Colorado at Boulder.
The ancient history of Neandertals in Europe
The ancient history of Neandertals in Europe
Early ancestors of the last Neandertals lived in Europe already 120,000 years ago
Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have retrieved nuclear genome sequences from the femur of a male Neandertal discovered in 1937 in Hohlenstein-Stadel Cave, Germany, and from the maxillary bone of a Neandertal girl found in 1993 in Scladina Cave, Belgium. Both Neandertals lived around 120,000 years ago, and therefore predate most of the Neandertals whose genomes have been sequenced to date.
By examining the nuclear genomes of these two individuals, the researchers could show that these early Neandertals in Western Europe were more closely related to the last Neandertals who lived in the same region as much as 80,000 years later, than they were to contemporaneous Neandertals living in Siberia. "The result is truly extraordinary and a stark contrast to the turbulent history of replacements, large-scale admixtures and extinctions that is seen in modern human history", says Kay Prüfer who supervised the study.
Intriguingly, unlike the nuclear genome, the mitochondrial genome of the Neandertal from Hohlenstein-Stadel Cave in Germany is quite different from that of later Neandertals - a previous report showed that more than 70 mutations distinguish it from the mitochondrial genomes of other Neandertals. The researchers suggest that early European Neandertals may have inherited DNA from a yet undescribed population. "This unknown population could represent an isolated Neandertal population yet to be discovered, or may be from a potentially larger population in Africa related to modern humans", explains Stéphane Peyrégne who led the analysis.
Press release from the Max Planck Institute for Evolutionary Anthropology / Max-Planck-Institut für evolutionäre Anthropologie
Neanderthals made repeated use of the ancient settlement of 'Ein Qashish, Israel
Neanderthals made repeated use of the ancient settlement of 'Ein Qashish, Israel
This site provides a rare opportunity to study long-term use of an open air settlement
The archaeological site of 'Ein Qashish in northern Israel was a place of repeated Neanderthal occupation and use during the Middle Paleolithic, according to a study released June 26, 2019 in the open-access journal PLOS ONE by Ravid Ekshtain of the Hebrew University of Jerusalem and colleagues.
In the Levant region of the Middle East, the main source of information on Middle Paleolithic human occupation comes from cave sites. Compared to open air settlements, sheltered sites like caves were easily recognized and often visited, and therefore are more likely to record long periods of occupation. The open-air site of 'Ein Qashish in northern Israel, however, is unusual in having been inhabited over an extended prehistoric time period. This site provides a unique opportunity to explore an open-air locality across a large landscape and over a long period ranging between 71,000 and 54,000 years ago.
In a joint collaboration with the Israel Antiquities Authority Ekshtain and colleagues identified human skeletal remains in 'Ein Qashish as Neanderthal and observed more than 12,000 artifacts from four different depositional units in the same location on the landscape. These units represent different instances of occupation during changing environmental conditions.
From modification of artifacts and animal bones at the site, the authors infer that the occupants were knapping tools, provisioning resources, and consuming animals on-site.
Whereas many open-air settlements are thought to be short-lived and chosen for specialized tasks, 'Ein Qashish appears to be the site of repeated occupations each of which hosted a range of general activities, indicating a stable and consistent settlement system. The authors suggest that within a complex settlement system, open-air sites may have been more important for prehistoric humans than previously thought.
Ekshtain adds: "Ein Qashish is a 70-60 thousand years open-air site, with a series of stratified human occupations in a dynamic flood plain environment. The site stands out in the extensive excavated area and some unique finds for an open-air context, from which we deduce the diversity of human activities on the landscape. In contrast to other known open-air sites, the locality was not used for task-specific activities but rather served time and again as a habitation location. The stratigraphy, dates and finds from the site allow a reconstruction of a robust settlement system of the late Neanderthals in northern Israel slightly before their disappearance from the regional record, raising questions about the reasons for their disappearance and about their interactions with contemporaneous modern humans."
The Neolithic precedents of gender inequality
The Neolithic precedents of gender inequality
Researchers from the University of Seville have published an ambitious study of gender inequality in prehistoric Iberia
Researchers from the Department of Prehistory and Archaeology at the University of Seville have studied the archaeological evidence of prehistoric societies in the Neolithic Period in the Iberian Peninsula from the perspective of gender. According to the results of their work, which address the analysis from the point of view of bioarchaeology and funerary archaeology, it was in the Neolithic that gender differences first appeared which meant male domination in later periods of history.
To arrive at these conclusions, the researchers have analysed two groups of indicators. On the one hand, life conditions and demographic aspects; and, on the other, funerary practices. In the first group, they studied factors like the sexual ratio (the demographic proportion of men to women), diet, genetic data, movement, the most common diseases and the detected stress markers. In the second, they considered data like the type of burial, the primary or secondary character of the deposit, if it was individual or collective burial, the spatial organisation of the site, the position and orientation of the bodies, the funerary goods that were placed in the tomb or the "funerary movements" (signs of manipulation of the bodies, pigmentation or alteration caused by the heat).
The study concluded that inequality between men and women was not generally consolidated or widely spread in Iberia during the Neolithic. However, situations progressively appeared that indicate dominance of men over women. The authors point to four important lines in which inequality between men and women can be investigated through successive historical periods: their access to funeral rites, the material conditions of their existence, the appearance of specific social roles for each of the genders and the growing association of men with violence.
It is precisely this last aspect that is most evident in this study. The arrow wounds on male bodies, the depositing of projectiles in their tombs or the pictorial representations (cave paintings) of men hunting and fighting have no equivalent parallel in women. Therefore, the authors point to the birth of an ideology that connected men with the exercise of force. In this sense, they highlight that the creation of different roles according to gender and other forms of gender inequality played a fundamental role in the growth of social complexity, a factor that has not always been well understood in previous research projects.
The study, which stems from the University of Seville doctoral thesis of Marta Cintas Peña, was carried out by the teacher Leonardo García Sanjuán, and it is the first time that this period has been dealt with from the perspective of gender and considering multiple variables. The study's conclusions mean the archaeological confirmation of the proposal of anthropologist Gerda Lerner, who in the book The Creation of Patriarchy proposed the hypothesis that it was the Neolithic societies that saw the beginning of inequality between men and women.
Press release from the University of Seville
Oldest flaked stone tools point to the repeated invention of stone tools
Oldest flaked stone tools point to the repeated invention of stone tools
A new archaeological site discovered by an international and local team of scientists working in Ethiopia shows that the origins of stone tool production are older than 2.58 million years ago. Previously, the oldest evidence for systematic stone tool production and use was 2.58 to 2.55 million years ago.
Analysis by the researchers of early stone age sites, published this week in the Proceedings of the National Academy of Sciences, suggests that stone tools may have been invented many times in many ways before becoming an essential part of the human lineage.
The excavation site, known as Bokol Dora 1 or BD 1, is close to the 2013 discovery of the oldest fossil attributed to our genus Homo discovered at Ledi-Geraru in the Afar region of northeastern Ethiopia. The fossil, a jaw bone, dates to about 2.78 million years ago, some 200,000 years before the then oldest flaked stone tools. The Ledi-Geraru team has been working for the last five years to find out if there is a connection between the origins of our genus and the origins of systematic stone tool manufacture.
A significant step forward in this search was uncovered when Arizona State University geologist Christopher Campisano saw sharp-edged stone tools sticking out of the sediments on a steep, eroded slope.
"At first we found several artifacts lying on the surface, but we didn't know what sediments they were coming from," says Campisano. "But when I peered over the edge of a small cliff, I saw rocks sticking out from the mudstone face. I scaled up from the bottom using my rock hammer and found two nice stone tools starting to weather out."
It took several years to excavate through meters of sediments by hand before exposing an archaeological layer of animal bones and hundreds of small pieces of chipped stone representing the earliest evidence of our direct ancestors making and using stone knives. The site records a wealth of information about how and when humans began to use stone tools.
Preservation of the artifacts comes from originally being buried close to a water source.
"Looking at the sediments under a microscope, we could see that the site was exposed only for a very short time. These tools were dropped by early humans at the edge of a water source and then quickly buried. The site then stayed that way for millions of years," noted geoarchaeologist Vera Aldeias of the Interdisciplinary Center for Archaeology and Behavioral Evolution at the University of Algarve, Portugal.
Kaye Reed, who studies the site's ecology, is director of the Ledi-Geraru Research Project and a research associate with Arizona State University's Institute of Human Origins along with Campisano, notes that the animals found with these tools were similar to those found only a few kilometers away with the earliest Homo fossils.
"The early humans that made these stone tools lived in a totally different habitat than 'Lucy' did," says Reed. "Lucy" is the nickname for an older species of hominin known as Australopithecus afarensis, which was discovered at the site of Hadar, Ethiopia, about 45 kilometers southwest of the new BD 1 site. "The habitat changed from one of shrubland with occasional trees and riverine forests to open grasslands with few trees. Even the fossil giraffes were eating grass!"
In addition to dating a volcanic ash several meters below the site, project geologists analyzed the magnetic signature of the site's sediments. Over the Earth's history, its magnetic polarity has reversed at intervals that can be identified. Other earlier archaeological sites near the age of BD 1 are in "reversed" polarity sediments. The BD 1 site is in "normal" polarity sediments. The reversal from "normal" to "reversed" happened at about 2.58 million years ago, geologists knew that BD 1 was older than all the previously known sites.
The recent discovery of older hammering or "percussive" stone tools in Kenya dated to 3.3 million years ago, described as "Lomekwian," and butchered bones in Ethiopia shows the deep history of our ancestors making and using tools. However, recent discoveries of tools made by chimpanzees and monkeys have challenged "technological ape" ideas of human origins.
Archaeologists working at the BD 1 site wondered how their new stone tool discovery fit into this increasingly complex picture. What they found was that not only were these new tools the oldest artifacts yet ascribed to the "Oldowan," a technology originally named after finds from Olduvai Gorge in Tanzania, but also were distinct from tools made by chimpanzees, monkeys or even earlier human ancestors.
"We expected to see some indication of an evolution from the Lomekwian to these earliest Oldowan tools. Yet when we looked closely at the patterns, there was very little connection to what is known from older archaeological sites or to the tools modern primates are making," said Will Archer of the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Cape Town.
The major differences appear to be the ability for our ancestors to systematically chip off smaller sharp-edged tools from larger nodules of stone. Chimpanzees and monkeys generally use tools for percussive activities, to hammer and bash food items like nuts and shellfish, which seems to have been the case with the 3.3 million year old Lomekwian tools as well.
Something changed by 2.6 million years ago, and our ancestors became more accurate and skilled at striking the edge of stones to make tools. The BD 1 artifacts captures this shift.
It appears that this shift in tool making occurred around the same time that our ancestor's teeth began to change. This can be seen in the Homo jaw from Ledi-Geraru. As our ancestors began to process food prior to eating using using stone tools, we start to see a reduction in the size of their teeth. Our technology and biology were intimately intertwined even as early as 2.6 million years ago.
The lack of clear connections with earlier stone tool technology suggests that tool use was invented multiple times in the past.
David Braun, an archaeologist with George Washington University and the lead author on the paper, noted, "Given that primate species throughout the world routinely use stone hammers to forage for new resources, it seems very possible that throughout Africa many different human ancestors found new ways of using stone artifacts to extract resources from their environment. If our hypothesis is correct then we would expect to find some type of continuity in artifact form after 2.6 million years ago, but not prior to this time period. We need to find more sites."
By 2.6 million years ago, there appears to be a long-term investment in tool use as part of the human condition.
Continued field investigations at the Ledi-Geraru project area are already producing more insights into the patterns of behavior in our earliest ancestors. New sites have already been found, and the Ledi-Geraru team will begin excavating them this year.
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This research was supported by the United States National Science Foundation and the John Templeton Foundation.
This research, "Earliest known Oldowan artifacts at >2.58 Ma from Ledi-Geraru, Ethiopia, highlight early technological diversity," is published in the Proceedings of the National Academy of Sciences.
Press release from the Arizona State University
Ancient DNA sheds light on Arctic hunter-gatherer migration to North America ~5,000 years ago
Ancient DNA sheds light on Arctic hunter-gatherer migration to North America ~5,000 years ago
An ancient population of Arctic hunter-gatherers, known as Paleo-Eskimos, made a significant genetic contribution to populations living in Arctic North America today
New research reveals the profound impact of Arctic hunter-gathers who moved from Siberia to North America about 5000 years ago on present-day Native Americans. Although this group is well-known from archaeology and ancient DNA, previous genetic studies suggested that they may have been largely replaced by the groups that gave rise to present-day Arctic peoples such as the Inuit, Yup’ik, and Aleuts. The present study proves that many present-day North Americans derive significant heritage from this ancient population.
The first humans in North America arrived from Asia some time before 14,500 years ago. The next major stream of gene flow came about 5000 years ago, and is known to archaeologists as Paleo-Eskimos. About 800 years ago, the ancestors of the present-day Inuit and Yup'ik people replaced this population across the Arctic. By about 700 years ago, the archaeological evidence for the Paleo-Eskimo culture disappeared. Their genetic legacy in living populations has been contentious, with several genetic studies arguing that they made little contribution to later North Americans.
In the current study, researchers generated genome-wide data from 48 ancient individuals and 93 modern individuals from Siberia, Alaska, the Aleutian Islands and Canada, and compared this with previously published data. The researchers used novel analysis methods to create a comprehensive model of population history that included many ancient and modern groups to determine how they might be related to each other. "Our study is unique, not only in that it greatly expands the number of ancient genomes from this region, but because it is the first study to comprehensively describe all of these populations in one single coherent model," states Stephan Schiffels of the Max Planck Institute for the Science of Human History.
Paleo-Eskimos left a lasting legacy that extends across North America
The researchers were able to show that a substantial proportion of the genetic heritage of all ancient and modern American Arctic and Chukotkan populations comes from Paleo-Eskimos. This includes people speaking Eskimo-Aleut languages, such as the Yup'ik, Inuit and Aleuts, and groups speaking Na-Dene languages, such as Athabaskan and Tlingit speakers, in Canada, Alaska, and the lower 48 states of the United States.
Based on the researchers' analysis, Paleo-Eskimos interbred with people with ancestry similar to more southern Native peoples shortly after their arrival to Alaska, between 5,000 and 4,000 years ago. The ancestors of Aleutian Islanders and Athabaskans derive their genetic heritage directly from the ancient mixture between these two groups. The researchers also found that the ancestors of the Inuit and Yup'ik people crossed the Bering Strait at least three times: first as Paleo-Eskimos to Alaska, second as predecessors of the Old Bering Sea archaeological culture back to Chukotka, and third to Alaska again as bearers of the Thule culture. During their stay in Chukotka that likely lasted for more than 1000 years, Yupik and Inuit ancestors also admixed with local groups related to present-day Chukchi and local peoples from Kamchatka.
Paleo-Eskimo ancestry is particularly widespread today in Na-Dene language speakers, which includes Athabaskan and Tlingit communities from Alaska and northern Canada, the West Coast of the United States, and the southwest United States.
"For the last seven years, there has been a debate about whether Paleo-Eskimos contributed genetically to people living in North America today; our study resolves this debate and furthermore supports the theory that Paleo-Eskimos spread Na-Dene languages," explains David Reich of Harvard Medical School and the Howard Hughes Medical Institute. "One of the most striking case examples from our study is the ancient DNA we generated from the ancient Athabaskan site of Tochak McGrath in interior Alaska, where we worked in consultation with the local community to obtain data from three approximately seven hundred year old individuals. We found that these individuals, who lived after the time when the Paleo-Eskimo archaeological culture disappeared across North America, are well modeled as a mixture of the same two ancestry components as those found in Athabaskans today, and derived more than 40% of their ancestry from Paleo-Eskimos.
A case example for how genetics can be combined with archaeology to shed new light on the past
The researchers hope that the paper will provide an example of the value of genetic data, in the context of archaeological knowledge, to resolve long-standing questions.
"Determining what happened to this population was not possible from the archaeological record alone," explains Pavel Flegontov of the University of Ostrava. "By analyzing genetic data in concert with the archaeological data, we can meaningfully improve our understanding of the prehistory of peoples of this region. We faced challenging analytical problems due to the complex sequence of gene flows that have shaped ancestries of peoples on both sides of the Bering Strait. Reconstructing this sequence of events required new modelling approaches that we hope may be useful for solving similar problems in other regions of the world."
Press release from the Max Planck Institute for the Science of Human History / Max-Planck-Instituts für Menschheitsgeschichte
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