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America was discovered by the Vikings … 400 years before Christopher Columbus

It was from the north that the Vikings would have discovered America around the year 1000. Pixabay – gloverbh222

The doubt was allowed since archaeological discoveries of a few decades ago. Now it is a fact: the presence of the Vikings in North America has been confirmed … 400 years before the arrival of Christopher Columbus.

We will have to review all the textbooks and update all our certainties on the discovery of the Americas. Until now, history has taught schoolchildren around the world that Christopher Columbus, funded by Queen Isabella of Spain, discovered America in 1492 while exploring a new sea route to India through the Atlantic Ocean.

Since archaeological excavations dating back 50 years, there was doubt about the identity of the first Europeans to have set foot on American soil. Indeed, traces of Vikings had been spotted in northeastern Canada in particular thanks to wooden objects.null

But this time, there is no longer any doubt. A study published in the journal Nature by the University of Groningen (Netherlands) toured the world on Wednesday, October 20. It indicates that researchers found a way to confirm the presence of the Vikings in Newfoundland, 400 years before the arrival (much further south) of Christopher Columbus.

A decisive solar storm

And it is the sun that enlightened the researchers. This is because a solar storm dated to AD 993 released a huge pulse of radiation that was absorbed and stored by trees all over the Earth. It was this solar event that turned out to be decisive in determining the exact year the Vikings were present in the Americas.

Until now, the wooden elements recovered 50 years ago had been dated but with the radiocarbon technique the margin of error was about a century. But researchers at the time had recovered and preserved hundreds of other additional pieces of wood found on and around the site, storing many in freezers in a Canadian warehouse to prevent them from rotting. 

A stock which represented a « gold mine » for the archaeologist of the University of Groningen, Margot Kuitems, co-author of the study.

The thing that changed everything is that three of the wood samples were from living trees during the solar event of 993. The cosmic storm was so powerful that it embedded itself in the layers of trees around the world. , creating a kind of timestamp of these.

This phenomenon having only occurred twice during the last 2000 years, it was then « easier » to date the pieces of wood … and in particular the year of the felling of the tree by the Vikings which dates back to the 1000s. Christopher Columbus did not land in San Salvador until 1492 …

Stephane Sicard

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Evolution: Why humans don’t have a tail

According to a preliminary study, the loss of this part of the body in humans is partly explained by the addition during evolution of a small sequence of DNA in a particular gene.

The best stories of scientific discovery always begin with an anecdote. “This question – where is my tail? – I’ve been running around in my head since I was a kid, ” says Bo Xia, a doctoral student in evolutionary biology at New York University School of Medicine.

He is the first author of a preliminary study – yet not peer reviewed – on tail loss in the animal kingdom. The New York Times is passionate about its story: “A bad Uber ride in 2019, in which Bo Xia injured his tailbone, brought this question to his mind with new urgency. ‘It took me a year to recover, and it really made me think about the tailbone.’ 

The importance of the TBXT gene

Uploaded to the bioRxiv platform on September 16 , the study suggests that tail loss is linked to the insertion of a small DNA sequence into a gene called TBXT. This gene was already suspected in previous studies to be involved in the formation or not of the tail in animals, specifies the American newspaper, but “the mutation that Bo Xia [and his team] discovered had not until then never been observed ”.

The researchers noted the presence of this mutation in humans and great apes, but not in other monkeys with tails. In this case, it is the addition of a short sequence, called Alu and recurrent in the human genome.

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Archaeology: 120,000 years ago, homo sapiens already made clothes

An international team made up of researchers from the Institute of Human Origins at Arizona State University and the Pan-African Evolution Research Group “Lise Meitner” from the Max Planck Institute for the Science of Human History (MPI- SHH) discovered a 120,000-year-old animal bone tool in Morocco.

The discovery takes place in the Smugglers Cave, near the Atlantic coast of Morocco, reports The National News . “The bone tools in the Smugglers’ Cave demonstrate that around 120,000 years ago, Homo sapiens began to intensify the use of bone to make formal tools and use them for specific tasks, including work. leather and fur, ”said study researcher Dr. Emily Hallett. This versatility seems to be at the root of our species and not a characteristic that emerged after the expansions in Eurasia. « 

She identified a pattern of cut marks on the bones of carnivores. According to her, the occupants of the cave skinned these bones for fur rather than turning them into meat. According to experts, the manufacture of clothes and the tools necessary to create clothes and shoes are milestones in the history of mankind, which makes it possible to discover the advances made by people in cultural and cognitive evolution. They believe that the clothes and tools used to make them were essential in enabling people to expand their niche from Pleistocene Africa to new environments that brought new ecological challenges.

Comparing the tools she identified with others in the archaeological records, Dr Hallett found that they had the same shapes and markings as the leather tools described by other researchers. « The combination of carnivore bones with skin marks and bone tools likely used for fur processing provides very suggestive indirect evidence for the earliest garments in the archaeological records, » she said. But given the level of specialization of this assemblage, these tools are likely part of a larger tradition with earlier examples that have yet to be found. « 

The researchers made another discovery, that of the tip of a whale or dolphin tooth that was compatible with use as a pressure flaker, a device used to shape stone tools. This is the first documented use of a marine mammal tooth by humans and the rest of the only Pleistocene marine mammal in North Africa.

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Cannabis cultivation began in China 12,000 years ago, study finds

According to a new genetic study published in the journal Science Advances , cannabis cultivation began in northwest China 12,000 years ago. An international team of researchers has traced the long history of human-weed relationships, and successfully demonstrated that cannabis was first cultivated by Chinese farmers, CNN reported on July 16.

The team, led by University of Lausanne biologist Luca Fumagalli, collected genomic data from 110 separate cannabis samples found across the world. These were both wild and cultivated plants, used to make industrial hemp, medical marijuana, and recreational cannabis, which share strong genetic ties. Thanks to this vast reservoir of genetic data, the team was able to identify the date and origin of human cultivation of cannabis.

“ We show that C. sativa [cannabis sativa] was first cultivated in the early Neolithic in East Asia, and that all current cultivars of hemp have diverged from an ancestral gene pool currently represented by plants. wild and landraces in China, ”the scientists write in the article.

Over the centuries of cultivation, two types of cannabis have emerged: hemp plants that are high in fiber but low in THC (the psychoactive ingredient in cannabis) and plants with a high THC concentration. This new study also shows that, despite their differences in composition, all of these varieties of marijuana share a single common ancestor, which has gradually spread throughout the world.

Source: CNN, Science AdvancesSponsored

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Discovery in China of a new species of prehistoric man

The new species was named Homo longi, which literally means « dragon man », a derivative of the name of the province where it was found.PHOTO XIJUN NI, AFP

) Neanderthals would ultimately not be modern man’s closest cousin. Scientists who analyzed a skull fossil found in China claim that it belongs to a new species of prehistoric man, less distant from us than the Neanderthals.

Harbin’s skull is particularly well preserved: it is the best-preserved fossil from this period (Middle Pleistocene), according to the researchers who published their work on Friday in the journal The Innovation . It dates from around 146,000 years ago.

« According to our analyzes, the Harbin group is more closely related to Homo sapiens than the Neanderthals are, » Chris Stringer, paleoanthropologist at the London Museum of Natural History and one of the co-authors of the study. “That is, Harbin shared a more recent common ancestor with us than the Neanderthals. « 

The genus Homo includes many extinct species, including Neanderthals, as well as our own, Homo sapiens – the only one now inhabiting the Earth.

The new species was named Homo longi, which literally means « dragon man », a derivative of the name of the province where it was found.

The skull was discovered in 1933 by a man working for the Japanese, who then occupied the region, during the construction of a bridge near the city of Harbin, in northeast China. .

Realizing the value of his find and not wanting it to fall into the hands of the Japanese, the man decided to « hide the skull in a well for a very long time, » Xijun Ni told AFP. lead authors of the study.

Learning his secret decades later, this man’s descendants finally donated the skull to Hebei GEO University in 2018.

Big and sturdy

The skull is a priori that of a man in his fifties, belonging to a population of hunter-gatherers.

His browbones are very large, as are his nose, almost square eye sockets and upper jaw. But it features delicate, flat cheekbones.

« The combination of an archaic but bulky cranial vault, and a large face but similar to Homo sapiens, is striking, » describes the study. This bone « differs from all other Homo species ».

These prehistoric humans were presumably tall and hardy.

« Based on the winter temperatures in Harbin today, you’d think they faced even more severe cold than the Neanderthals, » says Stringer. “This probably required both physical and cultural adaptations, but we cannot say more for now as we have no archaeological material associated” with this remains of Homo longi.

The researchers studied the morphology of the skull by isolating some 600 characteristic features, which they then compared using a powerful computer with those of other bones, in order to build a sort of huge family tree.

According to them, other specimens found in Asia (Dali, Jinniushan, Hualongdong, Xiahe) also belong to this new species.

« Third line »

Over 100,000 years ago, several human species coexisted on Earth across Europe, Africa and Asia, including Homo sapiens and Neanderthals.

This discovery « establishes a third human lineage in East Asia » alongside the latter two « and shows the importance of this region for human evolution, » insisted Chris Stringer.

One of the questions that remain to be clarified is whether this line is linked to the Denisovans, another species that evolved during this period, recently discovered thanks to DNA analyzes.

« I think it is quite possible that this skull (of Harbin) is a Denisovan skull […] but it will still take a lot of work to prove it, » said the paleoanthropologist.

The « dragon men » may have also been able to meet Homo sapiens, he believes.

« If the Harbin group forms a single group with the Denisovans, then we know that they did indeed reproduce with the Neanderthals and our own species, » said the researcher.

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Discovery in Israel of a new species of the genus Homo

Eight meters deep, at the prehistoric site of Nesher Ramla in Israel, Dr. Zaidner probably did not expect to make a discovery that would revolutionize our knowledge of the origin of Neanderthals.null

During excavations near the town of Ramla, researchers found prehistoric human remains that they could not attribute to a species of the genus  Homo already defined. In an article published in the journal  Science , a team of anthropologists from Tel Aviv University and a team of archaeologists from the Hebrew University of Jerusalem therefore define a new type of the Homo genus  , the Nesher Ramla type. This is the first described in Israel and is named after the site where it was discovered. The human remains, which consist of part of the cranial vault and a mandible , belonged to an individual who is believed to have lived between 140,000 and 120,000 years BC.

The morphology of these bones is remarkable in that some of the dental and jaw characters are common with those of Neanderthals , while those of the skull are shared with archaic individuals of the genus  Homo . In addition, the Homo type  of Nesher Ramla differs from modern man because of its cranial structure, because of its absence of a chin (which is a characteristic specific to  H. sapiens ) and the presence of very large teeth.

The authors also indicate that the fossil of the Man of Nesher Ramla was found in association with bones of horses, deer and aurochs as well as tools attesting to advanced stone cutting technology . The authors recall that this fossil of Man by Nesher Ramla is not the only one whose classification has baffled anthropologists . Several human fossils previously unearthed in Israel showed similar morphological characteristics and can now no doubt be attributed to this new type of the genus  Homo .

Bone remains belonging to Homo Nesher Ramla and found in Israel.  © Tel Aviv University
Bone remains belonging to  Homo Nesher Ramla and found in Israel. © Tel Aviv University  

Homo Nesher Ramla: the “missing” population?

Nesher Ramla’s discovery of the human type shakes up the hitherto privileged hypothesis of an emergence of Neanderthals in Europe which would then have migrated in small groups towards the south to escape the formation of glaciers and which would have reached Israel 70,000 ago. years. Rather, the fossil suggests that the ancestor of Neanderthals in Europe lived in the Near East 400,000 years ago and migrated several times to Europe and Asia.

This “missing” population in the fossil record to which Homo Nesher Ramla now belongs  is believed to be the source population from which most Pleistocene humans developed. This therefore implies that the Neanderthals of Western Europe would only constitute a residual population of a larger group originating in the Near East.

Cranial morphologies of several hominins.  © stockdevil, Adobe Stock
Cranial morphologies of several hominins. © stockdevil, Adobe Stock

The authors of the study further suggest that individuals of the Nesher Ramla type have reproduced with  Homo sapiens , which arrived 200,000 years ago in the Near East. The spatio-temporal localization of the fossil of Nesher Ramla would therefore make it possible to explain how genes of  H. sapiens were found in the European population of Neanderthals long before the arrival of modern humans in Europe. However, the fossil of the Man of Nesher Ramla does not contain DNA and although its belonging to a « source » population of the genus  Homo is today favored by the authors, it remains in suspense.

Source : futura Sciences

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Animal species comes back to life after 24,000 years in permafrost

The microscopic animal, called the bdelloid rotifer, survived in the Siberian permafrost for 24,000 years before resuming a normal life.

The scenario of this cryonics is worthy of a science fiction film. A team of scientists from the Soil Cryology Laboratory in Russia studied a microscopic animal species, the bdelloid, which survived in permafrost in Siberia for 24,000 years, reveals a study published on June 7, 2021 in the American scientific journal of cell biology Current Biology .

A species capable of putting its metabolism on hold for several thousand years

Taken 3.6 meters below the surface near the Alazeia River in northeastern Siberia, the bdelloids were brought to the surface for observation.

After thawing, the animal, about half a millimeter long, usually living in freshwater, came back to life. In a video published in the scientific journal, we can observe, thanks to a microscope, the bdelloïde move.

He was able to reproduce asexually using a self-cloning process called parthenogenesis and also began to eat normally.

The biological ability to put one’s life on hold for a long period in a frozen state raises many questions for scientists. « Our report is the strongest evidence to date that multicellular animals could endure tens of thousands of years in cryptobiosis, a state in which the metabolism is almost completely at a standstill, » said Stas Malavin, co-author of the study and member of the Institute of Physicochemical and Biological Soil Problems in Pouchtchino (Russia).

This discovery in permafrost adds rotifers to the list of multicellular organisms capable of surviving indefinitely.  » The bottom line is that a multicellular organism can be frozen and stored as such for thousands of years and then come back to life, a dream shared by many writers of fiction, » concludes Stas Malavin. .

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The secret weapon that allowed Homo sapiens to gain the advantage over Neanderthals

Researchers have discovered a series of genes linked to creativity that may have given Homo sapiens a significant advantage over Neanderthals.

Genes of creativity gave Homo sapiens an edge over Neanderthals. Photo Pierre ANDRIEU / AFP

How could Homo sapiens prevail against Neanderthals ? According to a study carried out by an international research team, and published Wednesday, April 21 in the journal Nature Molecular Psychiatry, the « secret weapon » of modern man, the one that allowed him to avoid extinction, was a series genes linked to creativity.

The results of the study suggest that these genes played « a fundamental role in the evolution of creativity, self-awareness and cooperative behavior ». These genes have indeed promoted « greater resistance to aging, injury and disease. »

267 unique genes in Homo sapiens

Led by the University of Granada in Spain, the experts behind the study identified 267 unique genes in modern humans and, through genetic markers, gene expression data and MRI techniques based on on artificial intelligence, discovered that they were linked to creativity.

“Scientists were able to identify regions of the brain in which these genes (and those with which they interacted) were overexpressed,” they wrote. « These regions (of the brain) are involved in human self-awareness and creativity, and include regions which are strongly associated with human well-being and which have arisen relatively recently. » 

According to the authors, creativity may have encouraged cooperation between individuals, which would have paved the way for technological innovation, behavioral flexibility and openness to exploration, thus allowing them to develop more successfully than their predecessors.

Very old brain networks

The same team of scientists had identified in the past a set of 972 genes organized into three brain networks, the oldest of which – which concerns learning habits, social attachment and conflict resolution – dates from 40 years ago. million years ago.  

The second network – which concerns intentional self-mastery – appeared 2 million years ago, while the most recent, which governs creative self-awareness, only appeared 100,000 years ago.

#Le Dauphiné

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Charles Darwin is not the first father of the theory of evolution, but the Iraqi scientist Al-Jahiz

About 1000 years before Charles Darwin wrote a book on how animals change through a process he called « natural selection, » a Muslim philosopher living in Iraq named Al-Jahiz had already preceded him. .

British scientist Charles Darwin’s theory of evolution is one of the cornerstones of modern science.

The idea that species gradually change over time through a mechanism called natural selection has revolutionized our understanding of the living world.

But it seems that the theory of evolution itself also has an ancestor in the Islamic world.

His real name Abu Usman Amr Bahr Bahr Alkanani al-Basri is remembered by history by his nickname, Al-Jahiz, which means someone whose eyes seem to be sticking out of their sockets.

His most famous work, The Book of Animals, is designed as an encyclopedia featuring 350 animals, in which Al-Jahiz presents ideas that bear a striking resemblance to Darwin’s theory of evolution.

« Animals engage in a struggle for existence and for resources, to avoid being eaten and to reproduce, » writes Al-Jahiz, « environmental factors influence organisms to develop new characteristics to ensure their survival. survival, thus transforming them into new species ”.

He adds, “Animals that survive to reproduce can pass their characteristics on to their offspring. « 

It was clear to Al-Jahiz that the living world was in constant struggle for survival and that one species was always stronger than another.

Charles Darwin rightly deserves his reputation as a scientist who has spent years traveling and observing the natural world, and who founded his theory with unprecedented precision and clarity to transform the way we see the world.

With BBC

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The mystery of the 2000-year-old “first computer” finally uncovered?

Part of the Antikythera Mechanism was exhibited at the Archaeological Museum of Athens in 2014.
Part of the Antikythera Mechanism was exhibited at the Archaeological Museum of Athens in 2014.

Researchers around the world have been wondering about the Antikythera mechanism for more than a century  . This machine, discovered by divers in 1901, has since been considered the world’s first analog computer, designed there? 2,000 years old. Today, scientists from London’s Global University (UCL), recognized worldwide for its academic excellence, believe they have solved the mystery of this pioneering computational object. Well, in part. They began to build a replica of the device with modern means, before doing the same with the techniques of Antiquity, revealed  The Guardian on  Friday March 12.

This astronomical calculator would have been able to display the movement of the Universe and predict the movement of the five planets known at the time, but also the phases of the Moon and solar and lunar eclipses.

Brass, cogwheels, dials?

Discovered in the middle of a treasure recovered from a merchant ship that languished off the Greek island of Antikythera, this supercomputer is made up of damaged fragments of brass and 30 bronze cogwheels connected to dials and pointers. However, two-thirds of the structure has not been found. After decades of academic work, scientists have concluded that this discovery is indeed a masterpiece of mechanical engineering.