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Grandpa Math Puzzles’ Oldest Ancestors Took Form on Egyptian Papyrus Dec 6, 2010 2:37 PM Math Puzzles’ Oldest Ancestors Took Form on Egyptian Papyrus British Museum CALCULATIONS The scribe of the Rhind Mathematical Papyrus, an Egyptian document more than 3,600 years old, introduces the roughly 85 problems by saying that he is presenting the “correct method of reckoning, for grasping the meaning of things and knowing everything that is, obscurities and all secrets.” By PAM BELLUCK Published: December 6, 2010 The first brain teasers were practical: problems to calculate how efficient a laborer was by how many logs he carried, or to gauge the potency of beer. I met a man with seven wives. ...” You may know this singsong quiz, But what you might not know is this: That it began with ancient Egypt’s Early math-filled manuscripts. It’s true. That very British-sounding St. Ives conundrum (the one where the seven wives each have seven sacks containing seven cats who each have seven kits, and you have to figure out how many are going to St. Ives) has a decidedly archaic antecedent. An Egyptian document more than 3,600 years old, the Rhind Mathematical Papyrus, contains a puzzle of sevens that bears an uncanny likeness to the St. Ives riddle. It has mice and barley, not wives and sacks, but the gist is similar. Seven houses have seven cats that each eat seven mice that each eat seven grains of barley. Each barley grain would have produced seven hekat of grain. (A hekat was a unit of volume, roughly 1.3 gallons.) The goal: to determine how many things are described. The answer: 19,607. The Rhind papyrus, which dates to 1650 B.C., is one of several precocious papyri and other artifacts displaying Egyptian mathematical ingenuity. There is the Moscow Mathematical Papyrus (held at the Pushkin State Museum of Fine Arts in Moscow), the Egyptian Mathematical Leather Roll (which along with the Rhind papyrus is housed at the British Museum) and the Akhmim Wooden Tablets (at the Museum of Egyptian Antiquities in Cairo). They include methods of measuring a ship’s mast and rudder, calculating the volume of cylinders and truncated pyramids, dividing grain quantities into fractions and verifying how much bread to exchange for beer. They even compute a circle’s area using an early approximation of pi. (They use 256/81, about 3.16, instead of pi’s value of 3.14159....) It all goes to show that making puzzles is “the most ancient of all instincts,” said Marcel Danesi, a puzzle expert and anthropology professor at the University of Toronto, who calls documents like the Rhind papyrus “the first puzzle books in history.” Dr. Danesi says people of all eras and cultures gravitate toward puzzles because puzzles have solutions. “Other philosophical puzzles of life do not,” he continued. “When you do get it you go, ‘Aha, there it is, damn it,’ and it gives you some relief.” But the Egyptian puzzles were not just recreational diversions seeking the comforting illusion of competence. They were serious about their mission. In the Rhind papyrus, its scribe, known as Ahmes, introduces the roughly 85 problems by saying that he is presenting the “correct method of reckoning, for grasping the meaning of things and knowing everything that is, obscurities and all secrets.” And the documents were practical guides to navigating a maturing civilization and an expanding economy. “Egypt was going from a centralized, structured world to partially being decentralized,” said Milo Gardner, an amateur decoder of Egyptian mathematical texts who has written extensively about them. “They had an economic system that was run by absentee landowners and paid people in units of grain, and in order to make it fair had to have exact weights and measures. They were trying to figure out a way to evenly divide the hekat so they could use it as a unit of currency.” So the Akhmim tablets, nearly 4,000 years old, contain lists of servants’ names, along with a series of computations concerning how a hekat of grain can be divided by 3, 7, 10, 11 and 13. The Egyptian Mathematical Leather Roll, also from about 1650 B.C., is generally considered a kind of practice test for students to learn how to convert fractions into sums of other fractions. The Rhind papyrus contains geometry problems that compute the slopes of pyramids and the volume of various-shaped granaries. And the Moscow papyrus, from about 1850 B.C., has about 25 problems, including ways to measure ships’ parts and find the surface area of a hemisphere and the area of triangles. Especially interesting are problems that calculate how efficient a laborer was by how many logs he carried or how many sandals he could make and decorate. Or the problems that involve a pefsu, a unit measuring the strength or weakness of beer or bread based on how much grain is used to make it. One problem calculates whether it’s right to exchange 100 loaves of 20-pefsu bread for 10 jugs of 4-pefsu malt-date beer. After a series of steps, the papyrus proclaims, according to one translation: “Behold! The beer quantity is found to be correct.” The problems in these ancient texts are not difficult by modern mathematical standards. The challenge for scholars has come in deciphering what the problems are saying and checking their accuracy. Some of the numerical equivalents are written in a symbolic system called the Eye of Horus, based on a drawing representing the eye of the sky god Horus, depicted as a falcon. Sections of the falcon’s eye are used to represent fractions: one-half, one-quarter and so on, up to one sixty-fourth. Scholars have found a few errors in the problems, and Ahmes even wrote an incorrect number in his St. Ives problem. But over all, the equations are considered remarkably accurate. “The practical answers are solved,” Mr. Gardner said. “What is unsolved about them is the actual thinking in the scribe’s head. We don’t know exactly how he thought of it.” http://www.nytimes.com/2010/12/07/science/07first.html?ref=science
MartiniLush Stonehenge twin – 'Timberhenge' – discovered with radar imaging Jul 22, 2010 12:32 PM Stonehenge, the mysterious circle of mammoth stone pillars in the middle of the English countryside, now has a slightly smaller twin. Scientist have discovered a second henge formation that once existed nearby made from huge timbers. And there could be many more henge-type circles yet to be found in the vicinity, says archeologist Vince Gaffney of the University of Birmingham, which is leading an expedition of the site along with the Ludwig Boltzmann Institute of Austria. "We didn’t expect to find another henge. There’s always been some presumption that the stones existed in splendid isolation," Professor Gaffney says. On July 16, just two weeks into their four-year project, Gaffney's team discovered ‘Timberhenge,’ a 25-meter (82-foot) diameter, circular series of holes that were once filled with 24 huge wooden poles. It sits about 900 meters away from Stonehenge in southern England. “Stonehenge isn’t the only henge monument in the area. There are several in the immediate vicinity,” says Dr. Gaffney, reached by phone today from Stonehenge. ‘Henge’ refers to a circular ditch with an external bank from the Neolithic period. Notably, not a bit of earth was dug up to make the discovery. Gaffney’s ground-mapping project uses radar-imaging equipment, which is placed a wheels and pulled over the fields surrounding Stonehenge. His team plans to scan a 14-square-kilometer (nearly 9 mile) area at a cost of $500,000 to $1 million. “We will not dig anything. The technologies we use will allow us to look at volumes of soil,” he says. The new Timberhenge appears built on the same orientation as Stonehenge, with entrances to the northeast and southwest. Archaeologists say it was a worshipping site and burial ground, but Gaffney says the precise role of the structures remains unclear: Was it for commoners or tribal leaders, worshippers or religious leaders? The radar-imaging project will provide a map of the area's structures and a clearer idea of its size and functions. Scientists have repeatedly unearthed new finds at Stonehenge. In October 2009, the Stonehenge Riverside Project uncovered a 10-meter (33-foot) diameter stone circle of bluestones, brought from the Preseli mountains of Wales, 150 miles away, and dubbed 'Bluestonehenge.' The stones, now missing, once marked the end of an avenue that leads from the River Avon to Stonehenge, a nearly 2-mile-long processional route constructed at the end of the Stone Age. Nor is this the first wooden henge found in the area. Two miles northeast of Stonehenge sits the so-called ‘Woodhenge,’ a six-ringed circle of 168 timber holes identified in 1925. Another timber circle nearby was identified in 1966. But Mike Parker Pearson of the University of Sheffield, director of The Stonehenge Riverside Project, says it's premature to describe this latest find as another "Woodhenge." "No one has any idea if these were circles of posts, stones or just pits. Nor do we know what date they are other than broadly 3000-1500 BC. They are both great finds but we know too little about them as yet (without excavation) to say how they will change our understanding," he says via email. "As we found last year with Bluestonehenge, there is still much to be found around Stonehenge." Gaffney agrees that much remains unknown. “Despite the fact that this is probably the most studied landscapes in the world…we know nothing about it,” says Gaffney. “Having said that, we felt we needed to know much more about what was happening between the monuments to know how it’s organized.” On Thursday, however, southern England’s summer rains had delayed further scans of the area, and sent Gaffney running for shelter in a car. “It’s raining heavily, so we’re not doing anything at the moment,” he told the Monitor. "It’s a British summer: what do you expect?" Source
Grandpa Signs of Neanderthals Mating With Humans May 7, 2010 2:49 AM   Advertise on NYTimes.com Signs of Neanderthals Mating With Humans Johannes Krause MPI-EVA The Vindija cave in Croatia where three small Neanderthal bones were found. Mixx MySpace Yahoo! Buzz Permalink Neanderthals mated with some modern humans after all and left their imprint in the human genome, a team of biologists has reported in the first detailed analysis of the Neanderthal genetic sequence. The New York Times Max-Planck-Institute EVA The Neanderthal DNA that Svante Pääbo analyzed came from these three bones. The biologists, led by Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have been slowly reconstructing the genome of Neanderthals, the stocky hunters that dominated Europe until 30,000 years ago, by extracting the fragments of DNA that still exist in their fossil bones. Just last year, when the biologists first announced that they had decoded the Neanderthal genome, they reported no significant evidence of interbreeding. Scientists say they have recovered 60 percent of the genome so far and hope to complete it. By comparing that genome with those of various present day humans, the team concluded that about 1 percent to 4 percent of the genome of non-Africans today is derived from Neanderthals. But the Neanderthal DNA does not seem to have played a great role in human evolution, they said. Experts believe that the Neanderthal genome sequence will be of extraordinary importance in understanding human evolutionary history since the two species split some 600,000 years ago. So far, the team has identified only about 100 genes — surprisingly few — that have contributed to the evolution of modern humans since the split. The nature of the genes in humans that differ from those of Neanderthals is of particular interest because they bear on what it means to be human, or at least not Neanderthal. Some of the genes seem to be involved in cognitive function and others in bone structure. “Seven years ago, I really thought that it would remain impossible in my lifetime to sequence the whole Neanderthal genome,” Dr. Paabo said at a news conference. But the Leipzig team’s second conclusion, that there was probably interbreeding between Neanderthals and modern humans before Europeans and Asians split, is being met with reserve by some archaeologists. A degree of interbreeding between modern humans and Neanderthals in Europe would not be greatly surprising given that the species overlapped there from 44,000 years ago when modern humans first entered Europe to 30,000 years ago when the last Neanderthals fell extinct. Archaeologists have been debating for years whether the fossil record shows evidence of individuals with mixed features. But the new analysis, which is based solely on genetics and statistical calculations, is more difficult to match with the archaeological record. The Leipzig scientists assert that the interbreeding did not occur in Europe but in the Middle East and at a much earlier period, some 100,000 to 60,000 years ago, before the modern human populations of Europe and East Asia split. There is much less archaeological evidence for an overlap between modern humans and Neanderthals at this time and place. Dr. Paabo has pioneered the extraction and analysis of ancient DNA from fossil bones, overcoming daunting obstacles over the last 13 years in his pursuit of the Neanderthal genome. Perhaps the most serious is that most Neanderthal bones are extensively contaminated with modern human DNA, which is highly similar to Neanderthal DNA. The DNA he has analyzed comes from three small bones from the Vindija cave in Croatia. “This is a fabulous achievement,” said Ian Tattersall, a paleontologist at the American Museum of Natural History in New York, referring to the draft Neanderthal genome that Dr. Paabo’s team describes in Thursday’s issue of Science . But he and other archaeologists questioned some of the interpretations put forward by Dr. Paabo and his chief colleagues, Richard E. Green of the Leipzig institute, and David Reich of Harvard Medical School. Geneticists have been making increasingly valuable contributions to human prehistory, but their work depends heavily on complex mathematical statistics that make their arguments hard to follow. And the statistical insights, however informative, do not have the solidity of an archaeological fact. “This is probably not the authors’ last word, and they are obviously groping to explain what they have found,” Dr. Tattersall said. Richard Klein, a paleontologist at Stanford, said the authors’ theory of an early interbreeding episode did not seem to have taken full account of the archaeological background. “They are basically saying, ‘Here are our data, you have to accept it.’ But the little part I can judge seems to me to be problematic, so I have to worry about the rest,” he said. In an earlier report on the Neanderthal genome, the reported DNA sequences were found by other geneticists to be extensively contaminated with human DNA. Dr. Paabo’s group has taken extra precautions but it remains to be seen how successful they have been, Dr. Klein said, especially as another group at the Leipzig institute, presumably using the same methods, has obtained results that Dr. Paabo said he could not confirm. Dr. Paabo said that episode of human-Neanderthal breeding implied by Dr. Reich’s statistics most plausibly occurred “in the Middle East where the first modern humans appear before 100,000 years ago and there were Neanderthals until 60,000 years ago.” According to Dr. Klein, people in Africa expanded their range and reached just Israel during a warm period some 120,000 years ago. They retreated during a cold period some 80,000 years ago and were replaced by Neanderthals. It is not clear whether or not they overlapped with Neanderthals, he said. These humans, in any case, were not fully modern and they did not expand from Africa, an episode that occurred some 30,000 years later. If there was any interbreeding, the flow of genes should have been both ways, Dr. Klein said, but Dr. Paabo’s group sees evidence for gene flow only from Neanderthals to modern humans. The Leipzig group’s interbreeding theory would undercut the present belief that all human populations today draw from the same gene pool that existed a mere 50,000 years ago. “What we falsify here is the strong out-of-Africa hypothesis that everyone comes from the same population,” Dr. Paabo said. In his and Dr. Reich’s view, Neanderthals interbred only with non-Africans, the people who left Africa, which would mean that non-Africans drew from a second gene pool not available to Africans.     http://www.nytimes.com/2010/05/07/science/07neanderthal.html
Grandpa A "missing link" between humans and their apelike ancestors has been discovered. Apr 3, 2010 9:25 PM A "missing link" between humans and their apelike ancestors has been discovered. By Richard Gray , Science Correspondent Published: 9:00PM BST 03 Apr 2010 Homo habilis lived 2.0-1.6 million years ago and had a wide distribution in Africa Photo: SPL The new species of hominid, the evolutionary branch of primates that includes humans, is to be revealed when the two-million-year-old skeleton of a child is unveiled this week. Scientists believe the almost-complete fossilised skeleton belonged to a previously-unknown type of early human ancestor that may have been a intermediate stage as ape-men evolved into the first species of advanced humans, Homo habilis . Related Articles Let children collect flowers and fossils says Sir David Attenborough T-Rex's long lost Australian cousin found for first time Jurassic Coast bans fossil hunters Attenborough's missing link Ida the 'missing link': fossil of man's earliest ancestor goes on display Scientists unveil stunning fossil Experts who have seen the skeleton say it shares characteristics with Homo habilis , whose emergence 2.5 million years ago is seen as a key stage in the evolution of our species. The new discovery could help to rewrite the history of human evolution by filling in crucial gaps in the scientific knowledge. Most fossilised hominid remains are little more than scattered fragments of bone, so the discovery of an almost-complete skeleton will allow scientists to answer key questions about what our early ancestors looked like and when they began walking upright on two legs. Palaeontologists and human evolutionary experts behind the discovery have remained silent about the exact details of what they have uncovered, but the scientific community is already abuzz with anticipation of the announcement of the find when it is made on Thursday. The skeleton was found by Professor Lee Berger, from the University of the Witwatersrand, while exploring cave systems in the Sterkfontein region of South Africa, near Johannesburg, an area known as "the Cradle of Humanity". The find is deemed to be so significant that Jacob Zuma, the South African president, has visited the university to view the fossils and a major media campaign with television documentaries is planned. Professor Phillip Tobias, an eminent human anatomist and anthropologist at the university who was one of three experts to first identify Homo habilis as a new species of human in 1964, described the latest discovery as "wonderful" and "exciting". Although not directly involved in the excavation and subsequent research on the fossils, he is one of the select few scientists outside the research group who have been able to see the skeletons. He said: "To find a skeleton as opposed to a couple of teeth or an arm bone is a rarity. "It is one thing to find a lower jaw with a couple of teeth, but it is another thing to find the jaw joined onto the skull, and those in turn uniting further down with the spinal column, pelvis and the limb bones. "It is not a single find, but several specimens representing several individuals. The remains now being brought to light by Dr Berger and his team are wonderful." The new fossil skeleton was found along with a number of other partially-complete fossils, encased within breccia sedimentary rock inside a limestone cave known as Malapa cave. The protection from the elements provided by the cave is thought to have played a large part in keeping the fossils so well preserved. The fossil record of early humans is notoriously patchy and scientists now hope that the that the new remains will provide fresh clues about how our species evolved. Scientists believe that a group of apelike hominids known as Australopithicus , which first emerged in Africa around 3.9 million years ago, gradually evolved into the first Homo species. Over time the Australopithicus species lost their more apelike features as they started to stand upright and their brain capacity increased. Around 2.5 million years ago Homo habilis , the first species to be described as distinctly human, began to appear, although only a handful of specimens have ever been found. It is thought that the new fossil to be unveiled this week will be identified as a new species that fits somewhere between Australopithicus and Homo habilis . If it is confirmed as a missing link between the two groups, it would be of immense scientific importance, helping to fill in a gap in the evolutionary history of modern man. Dr Simon Underdown, an expert on human evolution at Oxford Brookes University, said the new find could help scientists gain a better understanding of our evolutionary tree. He said: "A find like this could really increase our understanding of our early ancestors at a time when they first started to become recognisable as human." The discovery is the most important find from Sterkfontein since an almost-complete fossil of a 3.3 million year old Australopithecus , nicknamed Little Foot, was found in 1994. Another major discovery was the well-preserved skull of a 2.15 million year old Australopithecus africanus , nicknamed Mrs Ples, in 1947. Finding almost complete fossilised skeletons of human ancestors is particularly prized by the scientific community. The presence of a pelvis and complete limb bones would allow scientists to unravel the posture and method of walking used by the extinct species. If the specimen also contains hand bones, it could provide clues about the species' dexterity and such evidence will prove crucial in determining when the ability of modern humans to handle stone tools first emerged. Dr Kevin Kuykendall, a palaeoanthropologist at Sheffield University, said such finds were essential in helping to fill in the gaps in our knowledge about human ancestors. He said: "The information we have right now is probably only based on a few hundred individuals through out the whole world, but some of these are single isolated teeth. "If this new specimen is more complete and provides better information, all those models about locomotive behaviour will have a chance to really go under scrutiny and refined."   http://www.telegraph.co.uk/science/evolution/7550033/Missing-link-between-man-and-apes-found.html
Grandpa Scientists Rebuild Iceman Genome From Hair Sample Feb 13, 2010 2:36 PM Scientists Rebuild Iceman Genome From Hair Sample 1) – An international team of scientists has rebuilt the genome of an ancient human for the first time. Theubbed Inuk, was a Palaeo-Eskimo who lived about 4,000 years ago on the western coast of Greenland. Analysis of his genome, reported in the current issue of Nature , has given researchers new insights into the extinct Saqqaq culture – the first known to inhabit Greenland – but the work also revealed a variety of Inuk's physical traits. He had brown eyes, brown skin, shovel-shaped front teeth and a problem with dry earwax. He might have been going bald, too, but not completely. In fact, Inuk managed to leave behind a very valuable clump of hair. The lead scientists on the 53-person team, geneticists Eske Willerslev and Morten Rasmussen at the University of Copenhagen, found out about the hair, which had been excavated from permafrost in the 1980s, from an associate at the Natural History Museum in Denmark. One of the difficulties with analyzing ancient DNA is the risk of contamination from modern human DNA or damage inflicted by bacteria or fungi. But recent studies have shown that hair tends to protect DNA against the latter two threats. Nuka Godfredtsen An artist's drawing shows a reconstruction of "Inuk," a Palaeo-Eskimo who lived about 4,000 years ago on the western coast of Greenland. Willerslev took special care to guard against contamination as his group analyzed the sample. Still, these were 4,000-year-old locks, so it wasn't perfect. "We were dealing with very, very short pieces of DNA," Willerslev says. "It was a massive puzzle of 3.5 billion pieces that you have to stick together in the right way." That puzzle demanded help. Willerslev and his group did the initial analysis in Copenhagen, then shipped samples to labs in the United States, China, Great Britain and Australia; other scientists involved came from Estonia, France and Russia. "It was a huge amount of people involved in piecing all this together," he says. The group analyzed more than 350,000 of the genome's single nucleotide polymorphisms, or SNPs . In modern people, scientists have been able to link these tiny variations in DNA to a number of characteristics, so Willerslev and his group scoured DNA databases for SNPs that Inuk shares with modern people. The result was an unprecedented level of detail regarding the physical traits, metabolism and genetic predispositions of this ancient man. "I was actually quite surprised at the details we could get out of this," Willerslev says. "I think it's quite amazing that you could say that this guy had dry earwax." Besides ear wax and skin color, the genetic detective work also allowed the scientists to determine how the Saqqaq relate to other ancient and modern people. They concluded that Inuk's ancestors migrated to the New World from Siberia more than 4,400 years ago. Previously, researchers contended that the Saqqaq people were ancestors of the Inuit and Native Americans of today, but the genetic analysis shows this is not the case. "It was very clear that he's not ancestral to modern people found in the New World," Willerslev notes. "His closest relatives are three Siberian groups." Inspired by their success with Inuk, Willerslev and his team are now turning to a different continent. He plans to use similar techniques on 150 different ancient hair samples collected from all over South America, some of which date back 8,000 years. This next round of research will again address migration patterns, he says, but the scientists will also be exploring a phenomenon that could hold broader interest. "We're looking into the origin of clothes, and the clothes culture in the Americas." http://www.aolnews.com/science/article/scientists-rebuild-iceman-genome-from-very-old-hair-sample/19355181?icid=main|classic|dl1|link3|http%3A%2F%2Fwww.aolnews.com%2Fscience%2Farticle%2Fscientists-rebuild-iceman-genome-from-very-old-hair-sample%2F19355181

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Math Puzzles’ Oldest Ancestors Took Form on Egyptian Papyrus
Stonehenge twin – 'Timberhenge' – discovered with radar imaging
Signs of Neanderthals Mating With Humans
A "missing link" between humans and their apelike ancestors has been discovered.

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