Friday, 24 August 2012

Ancient Domesticated Remains Are Oldest in Southern Africa

ScienceDaily (July 11, 2012) — Researchers have found evidence of the earliest known instance of domesticated caprines (sheep and goats) in southern Africa, dated to the end of the first millennium BC, providing new data to the ongoing debate about the origins of domestication and herding practices in this region.

The full results are published July 11 in the open access journal PLoS ONE.

The researchers, led by David Pleurdeau of the National Museum of Natural History in Paris and Eugène Marais of the National Museum of Namibia, investigated remains from Leopard Cave in Namibia. They could not determine whether the remains came from a sheep or goats, but they write that there is no doubt that the teeth came from domesticated animals. These remains have been found associated with hundreds of archaeological findings, including stone and bone tools as well as beads and few potsherds.

The location and antiquity of the remains may provide further information about the domestication timeline, as well as potential movement patterns, for early herders in the region.

Hominins did not need boats to settle islands

12:00 12 July 2012 by Jeff Hecht
For similar stories, visit the Human Evolution Topic Guide

The early human colonisation of islands might not have been plain sailing. Instead of using boats to deliberately settle on Indonesian islands, hominins may have arrived as castaways, carried on floating debris after floods.

David Wilkinson of Liverpool John Moores University and Graeme Ruxton of the University of St Andrews, both in the UK, used population estimates from the early settlement of Polynesia to model the likely success of island settlement attempts in human prehistory.

They found that five young couples had a 40 per cent chance of giving rise to a population of 500 – or founding a population that survived for 500 years. Ten random castaways had only a 20 per cent chance of similar success. But throwing in between one and four additional castaways every 50 years raised the chances of an accidental settlement succeeding to 47 per cent.

Stone tools show that hominins – possibly Homo erectus – reached Flores 1 million years ago. The famous Homo floresiensis may have descended from this population of H. erectus. Meanwhile, a study earlier in the year concluded that Neanderthals had access to boats 100,000 years ago, which they used to reach the Greek islands of Lefkada, Kefallonia and Zakynthos, where their stone tools have been found.

The new finding suggests that in both cases the hominins could have reached the islands without boats. We already know that other mammals managed the feat: rats and Stegodon, an extinct relative of the elephant, crossed the deep-water channel between the Indonesian islands of Java and Flores. Elephants are strong swimmers, and rats could have travelled on storm debris.

Accidental colonisation of Flores by hominins would have been difficult, but not impossible, says Mike Morwood of the University of Wollongong in New South Wales, Australia. However, he adds, "the rapid colonisation of Greater Australia and major islands of western Melanesia 45,000 to 50,000 years ago indicates deliberate colonisation voyages by people using directed craft".

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A newly discovered American culture was present before ice age

A newly discovered American culture was present during, or even before, the Clovis culture in western North America.
The Western Stemmed culture of at least 13,200 years ago is defined by its distinctive projectile points.
Evidence is mounting that multiple migrations led to the first populating of the Americas.

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Bases of three Western Stemmed projectile points found in Oregon's Paisley Caves. Click to enlarge this image.
Jim Barlow

The first known people to settle America can now be divided into at least two cultures, the Clovis and the recently discovered "Western Stemmed" tradition, according to new research.

Researchers excavating an Oregon cave, found traces and unique tools made by a second people, who lived more than 13,200 years ago. The discovery, described in the latest issue of Science, strengthens the idea that that people moved into the Americas in several waves of migrations, not just one.

PHOTOS: Faces of Our Ancestors

"From our results, it is likely that we have at least two independent migration events to the lower 48 states," co-author Eske Willerslev of the University of Copenhagen's Center for GeoGenetics told Discovery News. "Additionally, we previously showed by sequencing the first ancient human genome (that of a 4,000-year-old paleoeskimo) that there have been at least two independent migrations into the Arctic parts of North America, so as I see it, it's likely we have at least around four migration events."

WATCH VIDEO: Clues from the pelvis of the human ancestor, Ardi, indicate she walked upright on two legs.

Willerslev added that three of these groups came from Asia, but the origins of the Clovis culture remain a mystery. What's now clear is that the newly discovered Western Stemmed culture was present at least 13,200 years ago, during or even before the Clovis culture in western North America.

The Clovis culture is defined by its "points," used for hunting. Lead author Dennis Jenkins explained that Clovis points are generally large "and have one or more distinctive flute flakes removed from the base so that a channel runs from the base up the blade roughly half way or slightly more to the tip."

Western Stemmed points, on the other hand, "are narrower, sometimes thicker, and thinned by percussion and pressure flakes from the edges to the midline." They were used as dart and thrusting spear tips, while Clovis points are generally assumed to be lance points.

The researchers aren't certain why these technologies diverged, probably long ago, from a common weapon-making tradition in Siberia or Asia. Since the early Americans only used one or the other method, the technologies suggest that the Clovis culture may have arisen in the Southeastern United States and moved west, while the Western Stemmed tradition began, perhaps earlier, in the West and moved east.

PHOTOS:Prehistoric Child Art Found in Caves

Jenkins, an archaeologist at the University of Oregon's Museum of Natural and Cultural History, and his team analyzed Western Stemmed points from Paisley Caves, located about 220 miles southeast of Eugene, Oregon. The researchers also studied dried human feces, bones, sagebrush twigs and other artifacts excavated from well-stratified layers of silt in the ancient caves.

Based on the analysis, it's believed that the people who lived at the same time as the Clovis were "broad range foragers, taking large game whenever possible, but also well adapted to a desert mosaic plant community similar, but not identical to, that of the northern Great Basin today," Jenkins shared.

If the oldest fossilized feces found in the caves (dating to 14,300 years ago) belonged to the Western Stemmed occupations, then the individuals hunted now-extinct horses, camels and elephants, in addition to deer, elk, mountain sheep, bison, waterfowl, rabbits and other animals.

HOWSTUFFWORKS: Were the Clovis the first Americans?

In a separate paper published in Nature this week, David Reich, a Harvard Medical School geneticist, and his team found that Native Americans descend from at least three streams of Asian gene flow. Most come from a single ancestral population, but the Eskimo-Aleut language speakers from the Arctic and the Na-Dene-speaking Chipewyan from Canada inherit some of their ancestry from different streams.

The way that these people entered the Americas might also have varied.

For decades, researchers have speculated that a temporary land bridge existed between Russia and Alaska. Evidence is also mounting for a "kelp highway" from Japan to Kamchatka, along the south coast of Beringia and Alaska, then southward down the Northwest Coast to California.

As to how people first wound up in Oregon, Jenkins said, "It is possible they represent a migration down the Pacific Coast followed by a migration inland."

Earliest Americans Arrived in Waves, DNA Study Finds

North and South America were first populated by three waves of migrants from Siberia rather than just a single migration, say researchers who have studied the whole genomes of Native Americans in South America and Canada.

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Kris Snibbe/Harvard

David Reich of Harvard and his team found that three migrant surges populated the Americas.

Emiliano Bellini

A sketch, based on photographs of Native Americans from the Arctic to Tierra del Fuego, illustrates new findings on the migration patterns of the first Americans.

Some scientists assert that the Americas were peopled in one large migration from Siberia that happened about 15,000 years ago, but the new genetic research shows that this central episode was followed by at least two smaller migrations from Siberia, one by people who became the ancestors of today’s Eskimos and Aleutians and another by people speaking Na-Dene, whose descendants are confined to North America. The research was published online on Wednesday in the journal Nature.

The finding vindicates a proposal first made on linguistic grounds by Joseph Greenberg, the great classifier of the world’s languages. He asserted in 1987 that most languages spoken in North and South America were derived from the single mother tongue of the first settlers from Siberia, which he called Amerind. Two later waves, he surmised, brought speakers of Eskimo-Aleut and of Na-Dene, the language family spoken by the Apache and Navajo.

But many linguists who specialize in American languages derided Dr. Greenberg’s proposal, saying they saw no evidence for any single ancestral language like Amerind. “American linguists made up their minds 25 years ago that they wouldn’t support Greenberg, and they haven’t changed their mind one whit,” said Merritt Ruhlen, a colleague of Dr. Greenberg, who died in 2001.

The new DNA study is based on gene chips that sample the entire genome and presents a fuller picture than earlier studies, which were based on small regions of the genome like the Y chromosome or mitochondrial DNA. Several of the mitochondrial DNA studies had pointed to a single migration.

A team led by David Reich of Harvard Medical School and Dr. Andres Ruiz-Linares of University College London reported that there was a main migration that populated the entire Americas. They cannot date the migration from their genomic data but accept the estimate by others that the migration occurred around 15,000 years ago. This was in the window of time that occurred after the melting of great glaciers that blocked passage from Siberia to Alaska, and before the rising waters at the end of the last ice age submerged Beringia, the land bridge between them.

They also find evidence for two further waves of migration, one among Na-Dene speakers and the other among Eskimo-Aleut, again as Dr. Greenberg predicted. But whereas Dr. Greenberg’s proposal suggested that three discrete groups of people were packed into the Americas, the new genome study finds that the second and third waves mixed in with the first. Eskimos inherit about half of their DNA from the people of the first migration and half from a second migration. The Chipewyans of Canada, who speak a Na-Dene language, have 90 percent of their genes from the first migration and some 10 percent from a third.

It is not clear why the Chipewyans and others speak a Na-Dene language if most of their DNA is from Amerind speakers. Dr. Ruiz-Linares said a minority language could often dominate others in the case of conquest; an example of this is the ubiquity of Spanish in Latin America.

If the genetics of the early migrations to the Americas can be defined well enough, it should in principle be possible to match them with their source populations in Asia. Dr. Greenberg had argued on linguistic grounds that the Na-Dene language family was derived from Ket, spoken by the Ket people in the Yenisei valley of Siberia. But Dr. Reich said there was not yet enough genomic data from Asia or the Americas to make these links. His samples of Na-Dene and Ket DNA did not match, but the few Ket samples he had may have become mixed with DNA from people of other ethnicities, so the test, in his view, was inconclusive.

The team’s samples of Native American genomes were drawn mostly from South America, with a handful from Canada. Samples from tribes in the United States could not be used because the existing ones had been collected for medical reasons and the donors had not given consent for population genetics studies, Dr. Ruiz-Linares said. Native Americans in the United States have been reluctant to participate in inquiries into their origins. The Genographic Project of the National Geographic Society wrote recently to all federally recognized tribes in the United States asking for samples, but only two agreed to give them, said Spencer Wells, the project director.

Interracial marriage — or admixture, as geneticists call it — may have distorted earlier efforts to trace ancestry because subjects assumed to be American may have had European or other DNA admixed in their genomes. Dr. Reich and his colleagues have developed a method to define the racial origin of each segment of DNA and have found that on average 8.5 percent of Native American DNA belongs to other races. They then screened these admixed sections out of their analysis.

Archaeologists who study Native American history are glad to have the genetic data but also have reservations, given that several of the geneticists’ conclusions have changed over time. “This is a really important step forward but not the last word,” said David Meltzer of Southern Methodist University, noting that many migrations may not yet have shown up in the genetic samples. Michael H. Crawford, an anthropologist at the University of Kansas, said the paucity of samples from North America and from coastal regions made it hard to claim a complete picture of early migrations has been attained.

“Sometimes the statisticians make wonderful interpretations, but you have to be very guarded,” he said.

The geneticists’ finding of a single main migration of people who presumably spoke a single language at the time confirms Dr. Greenberg’s central idea that most American languages are descended from a single root, even though the genetic data cannot confirm the specific language relationships he described.

“Many linguists put down Greenberg as rubbish and don’t believe his publications,” Dr. Ruiz-Linares said. But he considers his study a substantial vindication of Dr. Greenberg. “It’s striking that we have this correspondence between the genetics and the linguistics,” he said.

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EVOLUTION VS ADAPTATION NOAH AND THE ARK

The Creation Museum evolves: Hoping to add a life-size ark project, the museum hits fundraising trouble

Adam with a penguin and sheep in the Creation Museum's interpretation of the Garden of Eden. (Goodwin/Yahoo Ne …

Five years after it opened, the Creation Museum in Petersburg, Ky., still gleams, and life-size dinosaurs still tread the Earth, shoulder-to-shoulder with humans. But behind the scenes, one of the most ambitious efforts in America to counter evolutionary theory has hit a roadblock.
When you walk into the Creation Museum, one of the first things you see is an exhibit of a doe-eyed human child crouched next to a velociraptor dinosaur. The two seem not at all surprised that their epochs have collided. Homo sapiens and velociraptors missed each other by a good 65 million years, according to most scientists, but in the world of the Creation Museum, humans and dinosaurs were created on the same day 6,000 years ago, coexisting peacefully in the Garden of Eden. A thousand years later, a 600-year-old man ushered them onto Noah's ark.
Answers in Genesis, a ministry founded in Australia, built the Creation Museum. The group seeks to convince others that the theory of evolution is wrong and that the account of creation told in Genesis is literally true. The result: a place that resembles a slick and entertaining natural history museum, even as it peddles the exact opposite message.
Now, the people behind this museum are looking to erect something much bigger: a 160-acre park with a life-size replica of Noah's Ark built to stand 500 feet long and 80 feet high. They're hoping to tap four teams of Amish builders to construct this giant ark, which would become the largest timber structure in the country. Including parking and other areas, the entire Ark Encounter would sit on 800 acres about a 40-minute drive away from the Creation Museum in northern Kentucky.
But the ark plan now finds itself on troubled waters.
The group initially announced that it expected to break ground on the park in 2011, before eventually pushing that date back to 2014. But in June, in an interview in the Creation Museum's "Noah's Cafe," Ark Encounter vice president Michael Zovath told Yahoo News that the group no longer has a date in mind for the construction to begin. It has been unable to raise sufficient amounts of money, despite pleas to the Creation Museum's visitors to donate to the project.
"Fundraising is really tough," Zovath said, blaming the recession. "It's not moving so fast as we hoped." The private LLC that is building the park would need to raise another $20 million before it can break ground, he said. So far, it's taken in $5.6 million in donations and $17 million in private investments.
To add to the bad news, the Creation Museum is having its lowest attendance year yet. Last fiscal year, 280,000 people visited, compared to 404,000 the first year it opened in 2007. Zovath thinks that potential visitors have been less willing to travel to the museum because of the poor economy.
If the attraction does get built, it's unclear if it will be as controversial as the Creation Museum itself. The museum has draw criticism from atheists, scientists, educators (including the National Center for Science Education, which says kids who visit the museum will do worse in science classes), and fellow Christians who subscribe to a less literal, or "old Earth" view of Genesis, where the six days described in God's creation actually represent six long epochs. The museum strives to convince all visitors that the Earth is only 6,000 years old, instead of the 4.5 billion years that scientists endorse. (The museum motto: "Prepare to Believe.")
The Supreme Court has ruled that it's illegal for creationism to be taught in public schools, as a violation of the separation of church and state, so public school field trips are out.
But the museum still draws in plenty of school-age kids as visitors, in part by focusing on dinosaurs and savvy marketing campaigns. The museum has more than 100 billboards up around the country featuring cartoon dinosaurs urging drivers to make the trip.
"It's a way to get kids to come to the museum, that's the whole purpose of advertising," Zovath says of the ads. "The common response is, well, you're trying to attract children to your museum so you can teach them something we don't believe in. That's probably true," he concedes. "But secular museums and most natural history museums, when they run a dinosaur exhibit it's to promote attendance, and they're trying to teach kids things we don't believe in."
He added: "We have a message we want people to see, and the only way they'll see it is if they come to the museum."

Creation Museum exhibit. (Goodwin/Yahoo News)
In fact, many already agree with the message. About 46 percent of Americans think God created humans in their present form, while 32 percent say humans evolved, but God helped the process along, according to a recent Gallup poll. Fifteen percent think humans evolved and God had no part in the process.
Once the Ark Encounter is built, Zovath is hoping 1.6 million people will flock to it in its first year—and boost the Creation Museum's attendance, too. These projections, based on an outside consulting firm's analysis, helped score the park tens of millions of dollars in tax breaks from the state of Kentucky.
Ark Encounter will be a "Biblically themed attraction," not an amusement park, although there is one ride. "It's an indoor ride ... taking guests through the history of Israel from the call of Abraham and then Moses through the 10 plagues, and it ends with kind of a fun ride through the Red Sea as the Red Sea parts," Zovath says. Visitors are then deposited in a "first century village," to see what life was like when Jesus lived.
One Creation Museum visitor, Dennis Stevenson, a pastor in Lakewood, Wash., told Yahoo News he hopes Ark Encounter gets built, and he would definitely make the trip again to see the park. Stevenson teaches an adult class that covers Genesis as part of his ministry and has followed the creationism/evolution debate for years. "It's a subject I'm quite interested in," he said. "I just finished building my own six-foot model of the ark for my class."
While adults make up many of the visitors, the museum is full of questions and answers aimed at kids: Could this dinosaur fossil be millions of years old? ("No! The earth is just thousands of years old, so the fossils cannot be millions of years old.") What did dinosaurs eat? ("Before man's Fall, animals were vegetarians.") Is there any other evidence that dinosaurs lived after the Flood? ("Yes. Dragons may have been dinosaurs!") Did humans live with dinosaurs? ("Yes. God made Adam and Eve on the same day as land animals.")
In the gift shop, you can buy kids' T-shirts that say, "On the Sixth Day, God Created Dinosaurs!" or a book by Creation Museum founder Ken Ham titled, "The Great Dinosaur Mystery Solved."

Sometimes, the museum tackles evolution and its huge disagreement with science head-on, through exhibits on Charles Darwin and the Grand Canyon. At other times, certain displays seemed to entirely ignore the scientific consensus on an issue. A show on finches, a small type of bird that helped Darwin first hypothesize that one species of animal could turn into many different species, doesn't mention their key role in his scientific discovery. "Scientists are puzzled how so many finch species could arise, displaying such a vast array of traits," the exhibit reads. "The Bible provides the explanation. In the beginning of time, six thousand years ago, God created every kind of bird, including the finch kind, and He gave them the ability to 'multiply upon the earth.'"

But many visitors—even the littlest ones—seemed very familiar with evolution.

When I visited in June, a girl who looked about 10 years old rushed up to an exhibit that showed a giant hummingbird. Next to it, in shadow, were three other creatures—a pterodactyl, a bat and a small finch. "Look, this is evolution!" she said, pointing at the four creatures.

Her mother jerked her head around and walked up behind the girl. "You know what, honey? Those are just other animals that are designed to fly," she said, pointing at the exhibit's description.

"Oh," the little girl said, embarrassed she'd gotten it wrong.

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Atlantis, discovered off Scotland

Doggerland, northern Europe's own lost city of Atlantis, discovered off Scotland

A research diver inspects a collection of large stones on the seafloor of the North Sea, off Scotland's coast, which scientists say is evidence of human inhabitants on a once-dry expanse called Doggerland that stretched between Britain and Denmark. (University of St. Andrews)

(CBS News) LONDON - British scientists scouring the bottom of the North Sea have begun piecing together a picture of life in Doggerland, what they believe was the "heart of Europe," connecting modern day Britain to continental Europe, until about 7,000 years ago.

Among fossilized evidence of mammoths and large game animals, divers have found harpoons, flint tools and suspected burial sites they say belonged to residents of the submerged settlement more than 12,000 years ago.

A team organized by Dr. Richard Bates, a geophysicist at the University of St. Andrews, says the evidence points to a once-dry land passage between Scotland and Denmark which that was likely larger than many modern European cities, with tens of thousands of ancient humans calling it home.

"We haven't found an 'x marks the spot' or 'Joe created this', but we have found many artifacts and submerged features that are very difficult to explain by natural causes, such as mounds surrounded by ditches and fossilized tree stumps on the seafloor," explains Bates.

"There is actually very little evidence left because much of it has eroded underwater; it's like trying to find just part of a needle within a haystack," he adds. "What we have found though is a remarkable amount of evidence and we are now able to pinpoint the best places to find preserved signs of life."

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Doggerland discovered in the depths

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Bates says Doggerland was inhabited by a large number of hunters and gatherers, who roamed the ancient expanse of land stretching all around the British Isles and connecting what is now England to France and the Lowlands, and what is now Scotland to Denmark in the north.

The passage is believed to have been above land from about 18,000 BC until 5,500 BC, when rising sea levels and a devastating tsunami submerged the remaining islands.

Perhaps the most astounding aspect of the Doggerland discoveries is the insight it may provide into human life more than 12,000 years ago, particularly in difficult climates.

Bates says the findings suggest early man was able to survive, and thrive, "up through the north, more than we ever thought that they should."

Using a combination of geophysical modeling data from oil and gas companies, and direct evidence from materials recovered from the seafloor, the research team has been able to build a model of what the lost land likely looked like to its inhabitants.

"We have now been able to model its flora and fauna, build up a picture of the ancient people that lived there and begin to understand some of the dramatic events that subsequently changed the land, including the sea rising and a devastating tsunami," explains Bates.

The research team isn't finished yet. They're currently investigating further evidence of human presence and behavior in Doggerland, including possible human burial sites, intriguing standing stones and a mass mammoth grave.

The research project is a collaboration between St. Andrews and the Universities of Aberdeen, Birmingham, Dundee and Wales Trinity St. David. The artifacts go on display this week at The Royal Society's Summer Science Exhibition in London.

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