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The Story of Human Evolution Now Challenged

March 29, 2015 / / 0 Comments



Story of Human Evolution Challenged


Excerpt from newhistorian.com

The history of the evolution of early humans has been challenged.
Until now, one of the most dominant theories about our evolution claimed that our genus, Homo, had evolved from smaller early humans becoming taller, heavier and longer-legged. This process eventually resulted in Homo erectus, which was able to migrate out of Africa and colonise Eurasia.

Whilst we know that small-bodied H. erectus, averaging less than five feet tall and weighing under 50 kilograms, were living in southern Europe by 1.77 million years ago, the origin of the larger body size associated with modern humans has been elusive.

The paucity of knowledge about the origins of larger members of the Homo genus is primarily a result of a lack of evidence. Previous estimates of body size had been based on well-preserved specimens which were easy to assign a species to. Since these samples are rare and disparate in terms of both space and time, little is known about geographical and chronological variation in the body sizes of the early Homo.

A joint study between the Universities of Cambridge and Tübingen has shown that increases in body size occurred thousands of years after H. erectus left Africa; this growth in Homo body sizes primarily took place in the Koobi Fora region in modern Kenya.

“The evolution of larger bodies and longer legs can thus no longer be assumed to be the main driving factor behind the earliest excursions of our genus to Eurasia,” said Manuel Will, co-author of the study which has been published in the Journal of Human Evolution.

By using tiny fragments of fossil, the team were able to estimate our earliest ancestors’ height and body mass. Their findings, rather surprisingly, indicate a huge diversity in body size; this is particularly surprising as the wide variation we see in humans today was thought to be a relatively recent development.

“If someone asked you ‘are modern humans 6 foot tall and 70kg?’ you’d say ‘well some are, but many people aren’t,’ and what we’re starting to show is that this diversification happened really early in human evolution,” said Dr Jay Stock, co-author of the study.

Stock and Will are the first scientists in 20 years to compare the body size of humans from between 2.5 and 1.5 million years ago. They are also the first to use fragmentary fossils – many as small as toes, none longer than 5cm – to estimate body sizes.

By comparing measurements of fossils from sites in Kenya, Tanzania, South Africa and Georgia, the researchers have revealed substantial regional variation in the size of early humans. Groups who lived in South African caves, for example, were 4.8 feet tall on average. Some of the skeletons found in Kenya’s Koobi Fora region would have stood nearly 6 feet tall, a height comparable to the average height of modern British males.
“Basically every textbook on human evolution gives the perspective that one lineage of humans evolved larger bodies before spreading beyond Africa. But the evidence for this story about our origins and the dispersal out of Africa just no longer really fits,” said Stock.

It appears that Stock and Will have rewritten the history of the development of early humans; diversity has deep roots amongst the Homo genus.

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Circular thinking: Stonehenge’s origin is subject of new theory

March 24, 2015 / / 0 Comments




Excerpt from theguardian.com

Whether it was a Druid temple, an astronomical calendar or a centre for healing, the mystery of Stonehenge has long been a source of speculation and debate. Now a dramatic new theory suggests that the prehistoric monument was in fact “an ancient Mecca on stilts”.

The megaliths would not have been used for ceremonies at ground level, but would instead have supported a circular wooden platform on which ceremonies were performed to the rotating heavens, the theory suggests.

Julian Spalding, an art critic and former director of some of the UK’s leading museums, argues that the stones were foundations for a vast platform, long since lost – “a great altar” raised up high towards the heavens and able to support the weight of hundreds of worshippers.

“It’s a totally different theory which has never been put forward before,” Spalding told the Guardian. “All the interpretations to date could be mistaken. We’ve been looking at Stonehenge the wrong way: from the earth, which is very much a 20th-century viewpoint. We haven’t been thinking about what they were thinking about.”

Since Geoffrey of Monmouth wrote in the 12th century that Merlin had flown the stones from Ireland, theories on Stonehenge, from plausible to absurd, have abounded. In the last decade alone, the monument has been interpreted as “the prehistoric Lourdes” where people brought the sick to be healed by the power of the magic bluestones from Wales and as a haunted place of the dead contrasting with seasonal feasts for the living at nearby Durrington Walls. 

The site pored over by archaeologists for centuries still produces surprises, including the outline of stones now missing, which appeared in the parched ground in last summer’s drought and showed that the monument was not left unfinished as some had believed, but was once a perfect circle.

Spalding, who is not an archaeologist, believes that other Stonehenge theorists have fallen into error by looking down instead of up. His evidence, he believes, lies in ancient civilisations worldwide. As far afield as China, Peru and Turkey, such sacred monuments were built high up, whether on manmade or natural sites, and in circular patterns possibly linked to celestial movements.

He said: “In early times, no spiritual ceremonies would have been performed on the ground. The Pharaoh of Egypt and the Emperor of China were always carried – as the Pope used to be. The feet of holy people were not allowed to touch the ground. We’ve been looking at Stonehenge from a modern, earth-bound perspective.”
“All the great raised altars of the past suggest that the people who built Stonehenge would never have performed celestial ceremonies on the lowly earth,” he went on. “That would have been unimaginably insulting to the immortal beings, for it would have brought them down from heaven to bite the dust and tread in the dung.”

Spalding’s theory has not met with universal approval. Prof Vincent Gaffney, principal investigator on the Stonehenge Hidden Landscapes Project at Bradford University, said he held “a fair degree of scepticism” and Sir Barry Cunliffe, a prehistorian and emeritus professor of European archaeology at Oxford University, said: “He could be right, but I know of no evidence to support it”.
The archaeologist Aubrey Burl, an authority on prehistoric stone circles, said: “There could be something in it. There is a possibility, of course. Anything new and worthwhile about Stonehenge is well worth looking into, but with care and consideration.”

On Monday Spalding publishes his theories in a new book, titled Realisation: From Seeing to Understanding – The Origins of Art. It explores our ancestors’ understanding of the world, offering new explanations of iconic works of art and monuments.

Stonehenge, built between 3000 and 2000BC, is England’s most famous prehistoric monument, a UNESCO World Heritage site on Salisbury Plain in Wiltshire that draws more than 1 million annual visitors. It began as a timber circle, later made permanent with massive blocks of stone, many somehow dragged from dolerite rock in the Welsh mountains. Spalding believes that ancient worshippers would have reached the giant altar by climbing curved wooden ramps or staircases.

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Top Secret Government Programs That Your Not Supposed To Know About

March 23, 2015 / / 0 Comments

Originally Posted at in5d.com The following is the alleged result of the actions of one or more scientists creating a covert, unauthorized notebook documenting their involvement with an Above Top Secret government program. Government publications and information obtained by the use of public tax monies cannot be subject to copyright. This document is released into the public domain for all citizens of the United States of America. THE ‘MAJIC PROJECTS’ SIGMA is the project whic [...]

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Biologists fear DNA editing procedure can alter human DNA

March 20, 2015 / / 0 Comments




Excerpt from themarketbusiness.com

A group of biologists was alarmed with the use a new genome-editing technique to modify human DNA in a way that it can become hereditary.
The biologists worry that the new technique is so effective and easy to use that some physicians may push ahead with it before its safety can be weigh up. They also want the public to understand the ethical issues surrounding the technique, which could be used to cure genetic diseases, but also to enhance qualities like beauty or intelligence. The latter is a path that many ethicists believe should never be taken.

“You could exert control over human heredity with this technique, and that is why we are raising the issue,” said David Baltimore, a former president of the California Institute of Technology and a member of the group whose paper on the topic was published in the journal Science.

Ethicists have been concerned for decades about the dangers of altering the human germ line — meaning to make changes to human sperm, eggs or embryos that will last through the life of the individual and be passed on to future generations. Until now, these worries have been theoretical. But a technique invented in 2012 makes it possible to edit the genome precisely and with much greater ease. The technique has already been used to edit the genomes of mice, rats and monkeys, and few doubt that it would work the same way in people.

The new genome-editing technique holds the power to repair or enhance any human gene. “It raises the most fundamental of issues about how we are going to view our humanity in the future and whether we are going to take the dramatic step of modifying our own germline and in a sense take control of our genetic destiny, which raises enormous peril for humanity,” said George Daley, a stem cell expert at Boston Children’s Hospital and a member of the group.

The biologists writing in Science support continuing laboratory research with the technique, and few if any scientists believe it is ready for clinical use. Any such use is tightly regulated in the United States and Europe. American scientists, for instance, would have to present a plan to treat genetic diseases in the human germline to the Food and Drug Administration.

The paper’s authors, however, are concerned about countries that have less regulation in science. They urge that “scientists should avoid even attempting, in lax jurisdictions, germ line genome modification for clinical application in humans” until the full implications “are discussed among scientific and governmental organizations.”

Though such a moratorium would not be legally enforceable and might seem unlikely to exert global sway, there is a precedent. In 1975, scientists worldwide were asked to refrain from using a method for manipulating genes, the recombinant DNA technique, until rules had been established.

“We asked at that time that nobody do certain experiments, and in fact nobody did, to my knowledge,” said Baltimore, who was a member of the 1975 group. “So there is a moral authority you can assert from the U.S., and that is what we hope to do.”

Recombinant DNA was the first in a series of ever-improving steps for manipulating genetic material. The chief problem has always been one of accuracy, of editing the DNA at precisely the intended site, since any off-target change could be lethal. Two recent methods, known as zinc fingers and TAL effectors, came close to the goal of accurate genome editing, but both are hard to use. The new genome-editing approach was invented by Jennifer Doudna of the University of California, Berkeley, and Emmanuelle Charpentier of Umea University in Sweden.

Their method, known by the acronym Crispr-Cas9, co-opts the natural immune system with which bacteria remember the DNA of the viruses that attack them so they are ready the next time those same invaders appear. Researchers can simply prime the defense system with a guide sequence of their choice and it will then destroy the matching DNA sequence in any genome presented to it. Doudna is the lead author of the Science article calling for control of the technique and organized the meeting at which the statement was developed.

Though highly efficient, the technique occasionally cuts the genome at unintended sites. The issue of how much mistargeting could be tolerated in a clinical setting is one that Doudna’s group wants to see thoroughly explored before any human genome is edited.

Scientists also say that replacing a defective gene with a normal one may seem entirely harmless but perhaps would not be.
“We worry about people making changes without the knowledge of what those changes mean in terms of the overall genome,” Baltimore said. “I personally think we are just not smart enough — and won’t be for a very long time — to feel comfortable about the consequences of changing heredity, even in a single individual.”
Many ethicists have accepted the idea of gene therapy, changes that die with the patient, but draw a clear line at altering the germline, since these will extend to future generations. The British Parliament in February approved the transfer of mitochondria, small DNA-containing organelles, to human eggs whose own mitochondria are defective. But that technique is less far-reaching because no genes are edited.

There are two broad schools of thought on modifying the human germline, said R. Alta Charo, a bioethicist at the University of Wisconsin and a member of the Doudna group. One is pragmatic and seeks to balance benefit and risk. The other “sets up inherent limits on how much humankind should alter nature,” she said. 
Some Christian doctrines oppose the idea of playing God, whereas in Judaism and Islam there is the notion “that humankind is supposed to improve the world.” She described herself as more of a pragmatist, saying, “I would try to regulate such things rather than shut a new technology down at its beginning.”

Other scientists agree with the Doudna group’s message.
“It is very clear that people will try to do gene editing in humans,” said Rudolf Jaenisch, a stem cell biologist at the Whitehead Institute in Cambridge, Massachusetts, who was not a member of the Doudna group. “This paper calls for a moratorium on any clinical application, which I believe is the right thing to do.”
Writing in Nature last week, Edward Lanphier and other scientists involved in developing the rival zinc finger technique for genome editing also called for a moratorium on human germline modification, saying that use of current technologies would be “dangerous and ethically unacceptable.”

The International Society for Stem Cell Research said Thursday that it supported the proposed moratorium.

The Doudna group calls for public discussion but is also working to develop some more formal process, such as an international meeting convened by the National Academy of Sciences, to establish guidelines for human use of the genome-editing technique.

“We need some principled agreement that we want to enhance humans in this way or we don’t,” Jaenisch said. “You have to have this discussion because people are gearing up to do this.”

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Fresh fossil studies push the dawn of man back to 2.8 million years

March 4, 2015 / / 0 Comments

(Reuters) - A 2.8-million-year-old jawbone fossil with five intact teeth unearthed in an Ethiopian desert is pushing back the dawn of humankind by about half a million years.Scientists said on Wednesday the fossil represents the oldest known repres...

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Archaeologists Uncovering Legendary Lost City of Poseidon

February 6, 2015 / / 0 Comments

A view of the excavations at Helike. Drekis, Wikimedia CommonsExcerpt from popular-archaeology.com A team of scholars and students will return to explore and investigate the site now thought to be the remains of the lost city of Helike, the lege...

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The Mystery of the Blonde-haired Tarim Mummies of China

February 6, 2015 / / 0 Comments



Excerpt from 
historicmysteries.com
By Shelly Barclay

The Tarim Mummies or the Mummies of Xinjiang are mysterious mummies that were discovered in the foothills of the Tian Shan Mountains in China. What is so mysterious about them is that some of them date back to roughly 4,000 years ago, a time when it was thought that there were no westerners in that area. However, there must have been, because the Tarim mummies are Caucasian. Not only that, but they wear similar garments and share similar burial practices of some European countries.



The first of the Tarim mummies was discovered by Wang Binghua in 1978. Wang had been searching for ancient settlements along in the northeast of Xinjiang when a local man directed him to Quizilchoqa. It was there that Wang uncovered the first mysterious Tarim mummy. Over time, these mummies were discovered in four different sites in the Tarim Basin area.  More than one hundred of them have been uncovered so far.


The Tarim mummies are unusually well preserved. This is interesting because the people who buried them did not practice mummification. The sites where these mummies have been found, lie on the edges of the Taklamakan Desert. When these ancient people buried their dead, the hot climate and rocky soil helped to keep the deceased’s body preserved, though it should have decomposed hundreds of years ago. Some of these corpses rival the Ancient Egyptian mummies in their extraordinary preserved state.
Another very strange thing about the Tarim mummies is the attire in which they were buried. If the fact that some of them had blond hair and blue eyes hadn’t given away the fact that they were westerners that had settled in what is now Xinjiang, the clothing they wore when they were buried would have. 


One of the mummies, the Yingpan Man, was six feet six inches tall and wore a red tunic with gold embroidery. He also wore a gold foil burial mask. This burial clothing is far more indicative of western influence than of Eastern. Other Tarim mummies have also been found wearing decidedly western clothing. One of the oddest bits of clothing found any of these mummies are the flat-brimmed pointy “witch hats” that were discovered on the “Witches of Subeshi.”

Researchers have been able to decipher a number of things about the people who buried these mummies since their discovery. This is largely due to the work of Dr. Victor Mair, the man who brought the Tarim mummies into the public eye. It is known that the ancient people rode horses, used chariots and had at least some medical knowledge. One of the Tarim mummies was found with evidence of a surgical wound on its neck, which had been sutured at some point.

Since the discovery of the caucasian-featured Tarim mummies in Xinjiang, scientists have been trying to uncover links between the ancient people who buried these mummies and modern citizens of the area. Thus far, several links have been discovered and hypothesized, but it is difficult to make them public or credible because of political unrest in the area. Nonetheless, there are many people who are certain that the Tarim mummies represent the first Caucasians to settle in the area. If this is fact, then it will mean that western man settled in the area roughly one thousand years before scientists had previously thought they did.

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New internet neutrality: FCC chairman proposes strong new rules

February 5, 2015 / / 0 Comments

Excerpt from mercurynews.comThe federal government's top communications regulator on Wednesday called for strong new rules to bar Internet and wireless providers from blocking, slowing or discriminating against consumers' access to particular websi...

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New data on Easter Island’s mysterious past is a game-changer

January 13, 2015 / / 0 Comments





Excerpt from sciencerecorder.com


A study recently published in the Proceedings of the National Academy of Sciences suggests that harsh environmental conditions were the main source of population decline for the native Polynesians of Easter Island, potentially ending a long-standing debate over the exact cause.

Researchers of the study, led by Dr. Thegn Ladefoged of the University of Auckland in New Zealand, analyzed obsidian artifacts recovered from a number of habitation sites on the island to assess the regional land-use of the local inhabitants, known as the Rapa Nui.

The team found a shift in human uses of different parts of the island, suggesting an attempt to adapt to changing natural environmental conditions. Because of this, the researchers believe that natural barriers and climate extremes may have negatively impacted the islanders enough to lead to population declines.
“The results of our research were really quite surprising to me,” said Ladefoged, according to The Huffington Post. “In short, our research does not support the suggestion that societal collapse occurred prior to European contact due to physical erosion and productivity decline, but it does indicate that use of less optimal environmental regions changed prior to European contact.”

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Did drought doom the Mayan Empire? New evidence from Belize’s ‘Blue Hole’

December 30, 2014 / / 0 Comments




Minerals taken from lagoons reveal a century-long drought occurred between A.D. 800 and A.D. 900, right when the Mayan civilization disintegrated.

Excerpt from Livescience.com

By Tia Ghose  


Drought may have driven the ancient Mayan Empire to collapse, new research suggests.

Minerals taken from Belize's famous underwater cave, known as the Blue Hole, as well as lagoons nearby, show that an extreme, century-long drought occurred between A.D. 800 and A.D. 900, right when the Mayan civilization disintegrated. After the rains returned, the Mayans moved north — but they disappeared again a few centuries later, and that disappearance occurred at the same time as another dry spell, the sediments reveal. 

Rise and decline

From A.D. 300 to A.D. 700, the Mayan civilization flourished in the Yucatan peninsula. These ancient Mesoamericans built stunning pyramids, mastered astronomy, and developed both a hieroglyphic writing system and a calendar system, which is famous for allegedly predicting that the world would end in 2012.


But in the centuries after A.D. 700, the civilization's building activities slowed and the culture descended into warfare and anarchy. Historians have speculatively linked that decline with everything from the ancient society's fear of malevolent spirits to deforestation completed to make way for cropland to the loss of favored foods, such as the Tikal deer.

The evidence for a drought has been growing in recent years: Since at least 1995, scientists have been looking more closely at the effects of drought. A 2012 study in the journal Science analyzed a 2,000-year-old stalagmite from a cave in southern Belize and found that sharp decreases in rainfall coincided with periods of decline in the culture. But that data came from just one cave, which meant it was difficult to make predictions for the area as a whole, Droxler said.

The main driver of this drought is thought to have been a shift in the intertropical convergence zone (ITCZ), a weather system that generally dumps water on tropical regions of the world while drying out the subtropics. During summers, the ITCZ pelts the Yucatan peninsula with rain, but the system travels farther south in the winter. Many scientists have suggested that during the Mayan decline, this monsoon system may have missed the Yucatan peninsula altogether.

Deep history

The team found that during the period between A.D. 800 and A.D. 1000, when the Mayan civilization collapsed, there were just one or two tropical cyclones every two decades, as opposed to the usual five or six. After that, the Maya moved north, building at sites such as Chichen Itza, in what is now Mexico.

But the new results also found that between A.D. 1000 and A.D. 1100, during the height of the Little Ice Age, another major drought struck. This period coincides with the fall of Chichen Itza.

The findings strengthen the case that drought helped usher in the long decline of the Mayan culture.


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Dinosaur Researchers Say They’re in a ‘Golden Age’ of Discovery Due to the ‘Jurassic Park’ effect

December 30, 2014 / / 0 Comments




Excerpt from nbcnews.com

This was a great year for dinosaurs. Dreadnoughtus, "Jar Jar Binks," and a swimming Spinosaurus all made headlines — and 2015 could hold even more surprises. 

It wasn't always like this. From 1984 to 1994, there were about 15 new dinosaur species named per year. This year, nearly one species was discovered every week. 

"We're absolutely in a golden age of dinosaur discovery," David Evans, who oversees dinosaur research at the Royal Ontario Museum, told NBC News. "It is probably a better time to be a dinosaur paleontologist now than any other time in the last century." 

The 'Jurassic Park' effect

When it comes to finding dinosaurs in the dirt, paleontologists are using the same tools that they were 30 years ago. Satellite images might give them a better view of dig sites, but for the most part the process has not changed much. 

So why are there so many dinosaur discoveries these days? More people are looking for them. Evans estimates that the number of dinosaur paleontologists has more than quadrupled in the last 30 years. 

Every paleontologist interviewed for this story pointed to one catalyst for the paleontology boom: Steven Spielberg's 1993 blockbuster "Jurassic Park." 

"It put the most lifelike, scientifically accurate dinosaurs ever on the big screen," Evans said. "That helped the public moved beyond the classical view of dinosaurs as slow, dim-twitted creatures."
Famed Montana State University paleontologist Jack Horner admits he has a special affection for the film. He served as scientific adviser for the original "Jurassic Park" and was the inspiration for Dr. Alan Grant, the movie's protagonist. He also consulted on the upcoming "Jurassic World" starring Chris Pratt.

"'Jurassic Park' attracted an incredible number of people to the field," Horner told NBC News. "I'm hoping that we put together something cool with 'Jurassic World' that people will really like and get more children interested in paleontology." 

Increased interest led to increased paleontology budgets for museums and universities, Evans said. That has made a big difference in places like China and Argentina, relatively unexplored areas where a new generation of paleontologists has unearthed most of the recent headline-grabbing discoveries. 

"The number of dinosaur researchers is much higher now than in the '90s," Thomas Holtz, a vertebrate paleontologist at the University of Maryland, told NBC News. "Anytime you are exploring a region and a slice of time that hasn't been sampled before, chances are that everything you are finding is new."

2014 and beyond

Some of the biggest discoveries of the year were not new species. Instead, they were more complete fossils of dinosaurs the scientific community knew very little about. 

Take Spinosaurus, a massive carnivore that was even bigger than Tyrannosaurus rex. While its teeth indicated it ate fish, scientists were divided on whether it roamed the land and water looking for prey.

This year, the matter was settled. A new paper showed that the dinosaur's unique body structure — tiny hind limbs, dense bones, crocodile-like receptors in its snout — was best suited for the water and caused it to waddle on land. 

"That was probably the most significant find of the year," Horner said. 

There were other big discoveries in 2014. Dreadnoughtus fossils discovered in Argentina belonged to a creature that measured 85 feet (26 meters) long and weighed about 65 tons (59 metric tons), or about as much as a dozen elephants. 


Image: Deinocheirus mirificus, the largest known member of a group of ostrich-like dinosaurs 
This undated handout image provided by Michael Skrepnick, Dinosaurs in Art, Nature Publishing Group, shows a Deinocheirus mirificus, the largest known member of a group of bird-like dinosaurs.

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World’s Oldest Art Identified in Half-Million-Year-Old Zigzag

December 4, 2014 / / 0 Comments

A jagged line etched on a fossil mussel shell may be the oldest evidence of geometric art.Photograph by Wim Lustenhouwer, VU University Amsterdam(Reuters) - It's a simple zigzag design scratched onto the surface of a freshwater mussel shell on t...

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Elon Musk fears our progress in artificial intelligence is ‘seriously dangerous’

November 20, 2014 / / 0 Comments


 


Excerpt from
sciencerecorder.com



Visionary technology figure Elon Musk has been warning the public for months about possible threats posed by artificial intelligence. But now he has a timeline.

Musk, the South African-born CEO of Tesla Motors and SpaceX, wrote that “the risk of something seriously dangerous happening is in the five year time frame. 10 years at most.”

Musk penned this comment at the bottom of an essay written by virtual pioneer Jaron Lanier called “The Myth of A.I.” The essay appeared in the publication Edge.org last week and was followed by comments from such technology notables as George Dyson, Peter Diamandis, and Kevin Kelly.

While Musk’s comment was deleted, it was picked up by sites such as Mashable and Reddit, which preserved it for a larger audience. According to these sites, Musk zeroed in on companies such as DeepMind, a British artificial intelligence company that Musk once invested in before it was purchased by Google.

“The pace of progress in artificial intelligence (I’m not referring to narrow AI) is incredibly fast,” Musk’s piece read. “Unless you have direct exposure to groups like DeepMind, you have no idea how fast-it is growing at a pace close to exponential.”

Musk mentioned that AI companies “recognize the danger” and were working to ameliorate any negative intelligences “from escaping into the Internet.”

While Musk had sent his comment privately to Edge.org by email, it was published by a site editor before it was taken down. A Musk spokesperson has said that Musk will write a longer piece outlining his thoughts on the dangers of artificial intelligence, presumably to be published on the same website.

Previously, Musk has compared AI to “summoning the demon,” nuclear war, and the “Terminator” series.

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