Archaeologists say the shapes of finger marks suggest that children as young as 2 years old made drawings on the walls of a Paleolithic cave dwelling, with an occasional boost from the grown-ups.

The tale of the "prehistoric preschool" was laid out by Cambridge University archaeologist Jessica Cooney last weekend at a conference on the archaeology of childhood. Cooney has been studying hundreds of markings made on the walls of France's Rouffignac cave complex. Many of the markings are thought to date back 13,000 years, to a hunter-gatherer culture known as the Magdalenian. The same culture is thought to have created the better-known cave drawings at Lascaux.

Like Lascaux, the 5-mile (8-kilometer) Rouffignac cave network has plenty of drawings, depicting mammoths, rhinoceroses, horses and even a cave bear. But Cooney focuses on a different kind of art: impressions left behind in clay or "moonmilk" — a soft, white, crystalline precipitate that forms inside limestone caves. The ancient artists created the impressions by pressing or dragging their fingers through the soft material on the cave walls. Those markings are what Cooney and her research colleague, Walden University's Leslie Van Gelder, used to estimate how old the artists were. 

The analysis built upon years of research that Van Gelder conducted along with her late husband, archaeologist-theologian Kevin Sharpe. They measured the hands of thousands of modern-day people and came up with a correlation between the span of a person's three middle fingers and the person's age. For example, if the tips of the three fingers cover less than 1.3 inches (34 millimeters) in width, the fingers definitely belong to a child less than 7 years old, Cooney explained.

That modern-day analysis was then applied to the cave impressions, known as finger flutings.

"By 2006, Sharpe and Van Gelder had developed a way of determining the age and gender of children’s hand impressions, through the flutings," Cooney explained in Cambridge's news release. "As a methodology, it’s amazingly accurate.  By measuring the flutings at Rouffignac with callipers and matching them up against the modern data set, we can tell the age of the child who made them to up to 7 years old — and that is being conservative.  Similarly, if we have a clear finger profile, the shape of the top edges of the fingers, we can tell to 80 percent accuracy whether the individual was female or male. This works with both children and adults. Using methodology we can also identify marks made by the same child."

Cooney and Van Gelder spent a week making detailed measurements in the Rouffignac caves.

The researchers suspect that eight to 10 people, including four kids aged 7 or younger, were behind the ancient finger flutings. Children left marks in every chamber. One of them was apparently just 2 or 3 years old and may have been helped by a grown-up. "The most prolific of the children who made flutings was aged around 5 — and we are almost certain the child in question was a girl," Cooney said. 

Cooney said that child's markings appear on cave ceilings more than 6 feet (2 meters) high, which would suggest that she was held up or put on someone's shoulders to make the marks. One chamber was so marked up by children that it may have served as a "playpen of sorts," she said.

Finger flutings have been found not only in France and Spain, but in Australia and New Zealand as well. Were they mere doodles, or was there a deeper significance to the markings?

"We don’t know why people made them," Cooney said in the news release. "We can make guesses, like they were for initiation rituals, for training of some kind, or simply something to do on a rainy day.  In addition to the simple meandering lines, there are flutings of animals and shapes that appear to be very crude outlines of faces, almost cartoonlike in appearance. There are also hutlike shapes called tectiforms, markings thought to have a symbolic meaning which are only found in a very specific area of France. When in 2006 Sharpe and Van Gelder showed that that some of the tectiforms were the work of children, it was the first known instance of prehistoric children engaging in symbolic figure-making."

Personally, I lean toward the idea that the markings were the Paleolithic equivalent of kindergarten fingerpainting, but what do you think? Feel free to speculate in the comment section below.

More about prehistoric cave art:

• Altamira cave art in peril again, scientists say
• 'Cave' documentary is awesome and immediate
• Fungus threatens famed Lascaux cave drawings
• Gallery: Ancient rock art from around the world

For a guided tour of the Rouffignac cave complex's kiddie art, check out Rossella Lorenzi's report for Discovery News.

Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding me to your Google+ circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds. 

It may not be a $500 million golden hoard, but underwater archaeologists are nevertheless excited about finding what they believe are traces of the five ships that British privateer Henry Morgan lost off the coast of Panama in 1671.

The discovery was made at the mouth of Panama's Chagres River, near another underwater site where six iron cannons were found. Taken together, the evidence suggests that the three-century-old story of Captain Morgan's lost fleet is finally near its conclusion.

The story begins with Morgan, a Welsh sea captain who was given the British crown's official sanction to prey on Spanish sea trade. Some would call Morgan a pirate, others a buccaneer, but "privateer" is the more charitable term.

In 1671, Morgan aimed to weaken Spain's control of the Caribbean by sacking Panama City, and the first step was to capture Castillo de San Lorenzo, a Spanish fort on the cliff overlooking the entrance to the Chagres River. That river served as the only water passageway between the Caribbean and the capital.

Morgan and his pirates of the Caribbean took over the fort and went on to overwhelm the city's defenders. But in the process, he lost his flagship and four other ships to the rough seas and shallow reef surrounding the fort.

From there on, the story takes some dark twists and turns. Morgan had to move on to Panama City, abandoning the sinking ships. When the British buccaneers finally took over the city, they discovered that Spanish authorities had moved much of their treasure out to sea, beyond their reach. That made Morgan's men angry. Their mistreatment of the local citizenry in the wake of the "Sack of Panama" added to Morgan's disreputable image.

By the time he died in 1688, Morgan was seen as one of the most bloodthirsty (and most successful) pirates in the Americas. His exploits inspired enough pirate tales to fill a dead man's chest, including the Errol Flynn movie "Captain Blood" and the James Bond novel "Live and Let Die."

Any riches that may have been on Morgan's ships are thought to be long gone, thanks to treasure hunters who have plucked gold coins and other booty from the shallow waters of the Lajas Reef. But a team of U.S. archaeologists has been working to locate Morgan's ships and help the Panamanian government preserve the remaining artifacts.

'The story is the treasure'
"To us, the ship is the treasure — the story is the treasure," said Fritz Hanselman, an archaeologist with the River Systems Institute and the Center for Archaeological Studies at Texas State University. "And you don't have a much better story than Captain Henry Morgan's Sack of Panama City and the loss of his five ships."

Captain Morgan / Chris Bickford

A team of underwater archaeologists study the wreckage of a ship they believe to be part of Captain Henry Morgan's lost fleet.  The dive team discovered part of the starboard side of a 17th-century wooden ship hull and a series of unopened cargo boxes and chests encrusted in coral.

Volunteers from the National Park Service's Submerged Resources Center and the NOAA/UNC-W Aquarius Reef Base are working alongside Hanselman and other archaeologists and divers from Texas State University.

They knew they were on the right track last year when they discovered the 17th-century cannons. The experts widened their search, using a magnetometer that could pick up the signatures of objects buried beneath the sand and mud on the river bottom. Eventually, divers came upon a 52-by-22-foot section from the starboard side of a wooden ship's hull, along with unopened cargo boxes and chests encrusted in coral.

"We got really excited," Hanselman said in a video recounting the find.

Bert Ho, a survey archaeologist at the National Park Service, said the story behind the shipwrecks is being uncovered slowly through a series of dives. "Each dive tells us a little bit more, each archaeological drawing, each measurement — it all adds up," he said. "It's telling us the story of the wreck, the origin of the wreck, and hopefully the name of the wreck."

Captain Morgan / Chris Bickford

Bert Ho, an underwater project survey archaeologist with the National Park Service's Submerged Resources Center, based in Denver, maps the shipwreck with drawings using synthetic calque paper and plastic lead pencils. 

Yo ho ho and a bottle of rum
The extended search has been supported by a grant from the makers of Captain Morgan Rum, which was named after the 17th-century privateer.

"Captain Henry Morgan was a natural-born leader with a sense of adventure and an industrious spirit that the brand embraces today,” Tom Herbst, brand director for Captain Morgan USA, said in a statement. "When the opportunity arose for us to help make this discovery mission possible, it was a natural fit for us to get involved. The artifacts uncovered during this mission will help bring Henry Morgan and his adventures to life in a way never thought possible."

Herbst's company may win a share of the publicity for its role in the search for Captain Morgan's fleet, but it won't get any of the booty: Any artifacts excavated by the dive team belong the Panamanian government, to be preserved and displayed by the Patronato Panama Viejo.

More pirate lore:

• Artifacts reveal Blackbeard's terror tactics
• Blackbeard's anchor found off N.C. coast
• 10 shipwrecks that capture the imagination
• 12 pirate flicks worth digging up
• Yo ho ho: 10 pirate islands

Connect with the Cosmic Log community by "liking" the log's Facebook page or following @b0yle on Twitter. You can also add me to your Google+ circle, and check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Egypt Exploration Society / Oxford Imaging Papyri Project

A 3rd-century papyrus fragment contains a snippet of text from a non-canonical Christian gospel.

Scientists are recruiting thousands of armchair archaeologists to help them decipher a "lost" gospel and other fragments of texts from ancient Egypt.

The Ancient Lives project draws upon the same type of people power that drives citizen-science projects such as Galaxy Zoo, Planet Hunters,  Foldit and EteRNA. In all these cases, legions of human eyes and brains can do a better job of sifting through massive databases than supercomputers. For this particular project, however, the monster database that needs to be tamed does not consist of sky-survey data or molecular combinations — rather, they're ink letters, scrawled in Greek on centuries-old bits of papyrus.

Oxford University launched Ancient Lives just a couple of days ago, but project leader Chris Lintott told me that more than 400,000 papyrus images have already been served up as of today. "It's been a crazy few days," he said in an email.

Deluge of documents
That's the kind of participation Ancient Lives will need in order to cope with the deluge of documents from the Oxyrhynchus Papyri. More than a century ago, archaeologists unearthed piles of papyrus pieces in an ancient rubbish dump near an Egyptian city once known as Oxyrhynchus, about 100 miles (160 kilometers) south of Cairo. The manuscripts have been dated to between the 1st and the 6th century, covering a time when Greek and Roman culture was dominant in Egypt.

Egypt Exploration Society / Oxford Imaging Papyri Project

This papyrus from the 2nd or 3rd century is inscribed with an ink drawing showing the goddess Agnoia ("Ignorance"), from an illustrated edition of Menander's comedy "Perikeiromene," or "The Girl Who Had Her Hair Shorn."

Since its discovery, the treasure trove has yielded up some masterpieces of the age, including the comedies of Menander, the poems of Sappho and the gnostic Gospel of Thomas. Thousands of fragments have been cataloged and decoded. The only problem is, there are hundreds of thousands of fragments to go.

"Most of these haven't been read, and they weren't cataloged in what must have been extremely trying conditions in the field," said Lintott, an Oxford physicist and one of the pioneers behind Galaxy Zoo and its Zooniverse spin-offs. "As a result, our professional colleagues have been searching blind for the last century, like trying to do research by randomly selecting books off the Bodleian Library shelves."

University of Minnesota physicist Lucy Fortson, another project leader, said the fragments are completely out of sequence. "It's like if you have thousands of puzzles, take all the pieces and mix them together in one big box. Then you try to put the puzzles together," she said in a news release. "It's an enormous task."

Now the puzzle pieces have been digitized and made available for any Internet user to peruse.

"Until now, only experts could explore this incredible collection," Lintott said in this week's project announcement. "But with so much of the collection unstudied, there's plenty for everyone. We're excited to see what visitors can unearth."

Other leaders of the effort include Oxford's William MacFarlane, the lead developer and designer; James Brusuelas, the team's papyrologist; and Paul Ellis, an imaging specialist who helped digitize the texts. "It's with the digital advancements of our own age that we're able to open up this window into the past, and see a common human experience in that intimate, traditional medium, handwriting," MacFarlane said.

How you can help
The beauty part is that you don't even have to know Greek to help out. The online interface asks only that you compare the letters on each fragment with the shapes displayed on a keyboard. Lintott told me that the current plan calls for each fragment to be checked five times or so, to take advantage of the wisdom of crowds. Think of it as a variant of the "Captcha" type-in-the-phrase system that's used to block spammers.

Another task involves measuring the dimensions of the fragments, to help scholars figure out which fragments go together. You don't need a ruler: A click-and-drag measuring tool does all the work.

The transcribed fragments will be sent over to experts in ancient manuscripts for review, translation and potential publication. Will Internet users get credit for the work they've done? "Absolutely," Lintott said, "as with all Zooniverse projects, we'll take great care to attribute credit correctly."

Among the items recently picked out of the pile are fragments of a previously unknown apocryphal gospel that describes Jesus casting out demons, a lost play by Euripides titled "Melanippe the Wise" and newfound letters attributed to the philosopher Epicurus.

Who knows what else is waiting to be discovered? If you've ever wanted to put on an Indiana Jones fedora and delve into ancient mysteries, here's your chance. This tutorial shows you how the job is done, and this Zooniverse page is where you sign up to participate.

Update for 5:30 p.m. ET Aug. 1: Over the weekend, Oxford papyrologist James Brusuelas sent an email with further details about the juiciest bits of papyri:

"Gospel: In its current edited state, the gospel has not been overtly connected to any other sources. It remains a hot topic amongst historians of religion and Christianity. One must think about how the wider apocryphal (i.e., not included in the accepted canon of biblical texts) and biblical stories of Jesus relate to and inform the very act of casting out demons. Where does this particular narrative fit in the tradition of Jesus' acts? We have the text, we've identified it. Now it has to be studied and debated (that's why this project can be so cool).

"As for Euripides, we have the gist of the mythological story concerning Melanippe, her rape or seduction at the hands of Poseidon and the subsequent birth of twin sons, whom she tries to hide from her father Aeolus. All we know about the play is that it roughly begins as such:

"The children were hidden in a stable and discovered by a herdsman, who thought they were the unnatural offspring of a cow.

"Aeolus is persuaded to kill the twin as unnatural beings.

"Melanippe steps forward to rationally defend the children as the offspring of an unidentified girl.

"We've learned this from other sources that have quoted and given the background story to the myth, such as Dionysius of Halicarnassus, Aristotle, and Aristophanes.

"This roughly amounts to about 60 lines of the original text; everything pertains to the beginning of the story.

"Why is she wise? Her mother, Hippe, was the daughter of the wise centaur Chiron, the teacher and tutor of such great heroes as Ajax, Achilles, and Jason.

"How does the play unfold? We have no idea. And we don't know what we'll find, but we are waiting to learn how this story turns out."

More about citizen science:

• Archaeological vacations you'll really dig
• Japan's citizen scientists map radiation
• Join the online search for icy worlds
• Social networking to save frogs

Connect with the Cosmic Log community by "liking" the log's Facebook page or following @b0yle on Twitter. You can also add me to your Google+ circle, and check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

USDA

When humans first started to farm, we became shorter and less healthy. The effect didn't last forever, especially in the developed world following the industrialization of food systems, the researchers say. Shown here are wheat fields in eastern Washington.

People got shorter and sicker everywhere in the world when they started to farm, according to a recent study that suggests the transition to an agricultural lifestyle came at a biological cost.

The transition occurred at different times in different places around the world beginning about 10,000 years ago in the Fertile Crescent, an arc of land spanning modern day Egypt to the border between Iraq and Iran.

As people gave up the diverse diet of foraged foods and settled on eating a few staple food crops they "experienced nutritional deficiencies and had a harder time adapting to stress," Amanda Mummert, an anthropology graduate student at Emory University, said in a news release.

Compounding the problem, growth in population density spurred by agricultural settlements led to an increase in unsanitary conditions ripe for spreading infectious diseases and the transmission of novel viruses from livestock to humans, she added.

Eventually, this trend reversed itself and average heights for most populations began to increase. This is most evident in the 75 years or so since the industrialization of agriculture in the developed world.

The finding is based on a review of skeletal data on populations from various corners of the world, including China, Southeast Asia, and North and South America. Mummert and colleagues looked at skeletal height as well as dental cavities, bone density, and other indicators of health.

"Culturally, we’re agricultural chauvinists. We tend to think that producing food is always beneficial, but the picture is much more complex than that," Emory anthropologist George Armelagos, co-author of the review, said in the statement.

The findings support a theory he proposed in the 1984 book, "Paleopathology at the Origins of Agriculture," which showed a decline in health and rising nutritional diseases as humans shifted from foraging to agriculture. 

So, if the transition to agriculture was bad for our health, why did we do it? 

The geneticist Spencer Wells argues in his 2010 book, "Pandora's Seed: The Unforeseen Cost of Civilization,"  that the transition was driven by a cold snap between 12,700 and 11,500 years ago called the Younger Dryas. 

In the Near East, the cold spell was also a dry spell, which was bad news for hunter-gatherers there who had settled some of the world's first villages and subsisted on easily foraged fields of wheat and barley. 

The arid climate meant the grains clung to moist niches in the hills, not the valleys where the hunter-gatherers settled. The commute to the hills to forage grains was unsustainable. So someone — most likely a woman since they did most of the gathering — Wells argues, had the brilliant idea to plant grains closer to home. 

"Her first efforts must have been rewarded with admiration from the entire village," he writes. "Virtually overnight, humans had gone from being controlled by their food supply to controlling it." 

More on agriculture, health, and evolution:

• Humans still evolving as our brains shrink 
• Cow milk closely mimics that of human breast 
• Prehistoric feasting hall found 
• How climate change kills society 

Alex Chepstow-Lusty

Llama excrement was used as a fertilizer for the maize that helped build the Inca Empire, including Machu Picchu shown here.

The seeds of the Inca Empire were planted about 2,700 years ago when a warm spell combined with piles of llama excrement allowed maize agriculture to take root high up in the South American Andes, according to a new study.

"They were constructing fields and weeding them. And probably trading took off, made possible by llama caravans transporting goods, such as maize, coca leaves, salt and a ceremonial product called cinnabar," Alex Chepstow-Lusty of the French Institute of Andean Studies in Lima told me Sunday in an email.

The finding is inferred by a record of pollen and mites in a core of mud taken from a small lake located at about 11,000 feet up in the Andes surrounded by agricultural terraces and next to an ancient trading route that connected tropical forest and mountain communities.

The Laguna Marcacocha core extends back over 4,200 years. The pollen tells Chepstow-Lusty about what plants were growing around the lake when. Mites eat plant detritus such as that found in excrement. "The more excrement, the more mites living in the soils close to the lake," he explained. 

Record extended
In previous research based on the core, Chepstow-Lusty showed how a period of global warming starting around A.D. 1100 allowed the expansion of the Inca Empire by allowing the growth of maize,  known in the U.S. as corn, to feed armies of people constructing roads and monuments such as Machu Picchu.

The new research, published in the June issue of the journal Antiquity, extends the record back several more thousand years and pinpoints when agricultural and trade first took off in Andes around Cuzco, which became the seat of the Inca Empire.

Prior to cultivating corn, humans were eating wild quinoa, part of the spinach family. "Quinoa favors colder and drier conditions than maize, and does not provide the calories that maize does," Chepstow-Lusty said.

Alex Chepstow-Lusty

A core of mud taken from a small lake high in the Andes shows when and how maize agriculture helped build the Inca Empire.

In addition to quinoa, potatoes were also likely a major source of calories, but potato pollen is difficult to discern in the lake core. However, other researchers suggest that the weight and perishable nature of potatoes made them useful only to local communities.

Maize is easily transported and stored, which makes a surplus possible that can be extracted as payment to a political system. Hence maize, like barley and wheat in the Near East, is considered essential for the development of civilization in the Americas. 

However, in order to grow the grain at large enough scale to feed the armies needed to build the Inca Empire, a source of organic fertilizer was needed, Chepstow-Lusty argues. That, he said, was found in llama excrement, which was in abundance at the same time maize appeared in the record.

"Camelids defecate communally, so their dung can be accumulated in a small area and constitutes a regular supply that is easily exploitable by the local population," he writes in Antiquity.

"Hence it is no coincidence that the shift to agriculture corresponds with a distinct peak in oribatid mites, suggesting increased pastoralism, greater availability of excrement and potentially a major trading network."

Periodic warming
From about 700 B.C., the lake core record paints a picture of warm, dry spells in the high Andes about every 500 years that correspond with major societal changes. When the climate cooled, societies would retreat down slope, returning once it warmed again.

According to Chepstow-Lusty, the sustained warming beginning around A.D. 1100 allowed populations to move even higher up in the Andes "and grow a lot more maize and support even bigger populations."

Maize, in addition to being a source of food, is the basis of chicha, a corn-based beer that was central to the ceremonial life of Native American cultures.

"I am sure ritual ceremonies began on a large scale at the same time from 2,700 years ago and helped bind the members of different groups together, even libations for the dead and the gods," Chepstow-Lusty added.

More stories on the Inca:

• Inca children 'fattened up' before sacrifice
• Global warming may have aided Inca Empire 
• 'Lost city of the Incas' was not a true city
• Possible pattern found in Incan strings 

Current Anthropology

Archaeologists have discovered the oldest mine in the Americas along the coast of northern Chile. The iron-oxide mine dates to about 12,000 years ago.

Archaeologists have discovered a 12,000 year old iron-oxide mine along the coast of northern Chile that they say is the oldest evidence of organized mining found in the Americas.

The mine — essentially a 130-foot long and 20-foot wide trench — was found near Taltal by a team of researchers led by Diego Salazar from Universidad de Chile.

It was dug by the Huentelauquen people, a hunter-gatherer fisher group who were the first settlers of the region.

The iron oxide was used as a pigment primarily for symbolic purposes, the team reports in the June issue of Current Anthropology.

Remains indicate the pigment was used to paint stone and bone instruments. It was likely used in clothing and body paint as well, the researchers note.

While these uses of the pigment are widely known, the history of how indigenous groups exploited and processed the minerals is poorly understood.

The new find sheds light on the techniques and technologies to mine it, including the recovery of nearly 500 hammerstones that date back to the earliest use of the mine.

An estimated 25,000 cubic feet and 2,000 tons of rock were excavated from the mine from around 12,000 years ago to 10,500 years ago and again around 4,300 years ago, according to radio carbon dates from charcoal and shells found in the mine.

The earliest stages of production of the mine are contemporary with the oldest human occupations in northern Chile, the researchers note, and extends by several thousand years the record of mining in the Americas.

The duration and extent of the operation, the researchers add, indicates "the techniques required to exploit and process these minerals were transmitted over generations."

Before this find, a North American copper mine dated to between 4,500 and 2,600 years ago was the oldest known in the Americas.

via Eurekalert

John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).

University of Kansas

Teeth show markings of a right-handed person. The markings are from accidental tooth whacking by people using stone tools, according to researchers.

Lefties were as outnumbered 600,000 years ago as they are today, according to telltale markings on teeth found on Neanderthal and Neanderthal ancestors in Europe.

The finding serves as a new technique to determine whether a person was left- or right-handed from limited skeletal remains, and it also suggests that a key piece for the origin of language was in place at least half a million years ago, David Frayer, an anthropologist at the University of Kansas, told me today.

But while ancient righties appeared to outnumber lefties nine to one, the findings don't reveal whether some of the ancient lefties dominated in sports, as baseball players do today; and in politics, where being left-handed seems to help open the door to the White House.  

Tooth markings
The telltale tooth markings, based on experiments, appear to result from how these Neanderthals and their relatives processed hides with stone tools, explained Frayer, a co-author of a paper on the findings published this month in the journal Laterality.

One of his colleagues in Spain had people wear a mouth guard and then strike a hide as if they were cutting or stretching it with a stone tool. Every now and then, the test subjects were asked to whack their guarded teeth, as the researchers think would have accidentally happened as the ancient humans worked away.

AFP - Getty Images file

A reconstructed Neanderthal appears to strike a pose at the Prehistoric Museum in Halle, Germany.

Imagine a person pulling on the hide with their left hand and striking it with a tool held in their right hand. When they accidentally hit a tooth, the angle of the strike would be from the upper left to the lower right, Frayer explained.

"It doesn't matter what tooth it was, it would always be in that direction," he told me. "That tells you if you see scratches that are running in that direction, it tells you that the individual was primarily using their right hand to process."

Markings primarily going the opposite way — from the upper right to the lower left — are the sign of a lefty.

Frayer and colleagues examined isolated teeth from 27 Neanderthal and Neanderthal ancestors from Europe dating back 600,000 years and found that 25 of them have the telltale markings of a righty.

"That's the pattern we see in modern populations," Frayer noted, suggesting that right-handed dominance is an ancient human trait.

Language link
Although some studies of tool-using chimpanzees suggest a preference for the left hand, the ratio isn't as sharp as 9 to 1, according to Frayer. Such a distinctive ratio of handedness is unique to humans and their immediate ancestors and relatives.

And such laterality, he adds, appears linked to the development of language, a skill that humans have and chimps don't.

"The connection is the left side of the brain controls the right side of the body, and language is located on the left side," Frayer said.

We know this because when people experience a stroke on the left side of the brain, their speech is impaired and they lose control of the right side of their body. A person who has a stroke on the right side of the brain retains the ability to talk, but loses control of the left side of their body.

Finding that right-handedness goes back at least 600,000 years thus suggests that this key piece for language was in place, "so the people probably spoke," Frayer said.

More stories on handedness:

• Tool using chimps mostly lefties, study finds
• Hand preference in humans, animals explained
• Brain zap may improve righties' use of left hand
• Left handed hitters have a built in advantage

Nasser Nasser / AP

This file photo shows Seif al-Islam Gadhafi at a ceremony of the declaration of a sustainable environmental region at the ancient city of Cyrene near the city of al-Bayda, northeastern Libya Sept. 10, 2007.The site is one of five World Heritage Sites in the country.

Though reportedly safe for now, as the tension escalates in Libya, the fate of the country's archaeological heritage is increasingly uncertain, experts say. Meanwhile, in Egypt, threats to national treasures may resurface, after a pause.

The last of the foreign archaeologists working in Libya were evacuated Feb. 26, according to Nature News. The 11 archaeologists with the Italian-Libyan Archaeological Mission in the Acacus and Messak are studying ancient archaeology and rock art in the country.

Savino di Lernia, head of the team, relayed a message from Salah Agab, chairman of the Libyan Department of Antiquities, that currently the situation was under control and all museums and archaeological sites are safe.

But archaeologists fear the chaos and risk of looting poses a threat to the country's ancient archaeological sites, as they have in the recent uprisings in nearby countries such as Egypt.

Security is described as "good" at the Libya's five World Heritage sites, including the Roman ruins of Leptis Magna, a prominent coastal city of the Roman Empire about 80 miles east of Tripoli that is renowned for its public monuments, harbour, market-place, storehouses, shops and residential districts.

Other World Heritage sites include the ancient Greek archaeological sites of Cyrene; the Phoenician port of Sabratha; the rock-art sites of the Acacus Mountains in the Sahara Desert; and the old town of Ghadamès, an oasis city that has been home to Romans, Berbers and the Byzantine civilization.

The situation could be "problematic" elsewhere, di Lernia told Nature News.

The capital city, Tripoli, remains tightly controlled by Gadhafi's heavily armed forces, who this week launched counterattacks against nearby cities controlled by protesters. Despite the security presence, important sites in this northwestern region, such as Sabratha, are "really endangered."

A report from Reuters paints a similar picture of concern about the country's cultural heritage: 

"So far there are no records whatsoever of any areas from the cultural heritage of Libya being affected by the troubles," said Hafed Walda, a Libyan who advises the country's department of antiquities and once led an excavation at Leptis Magna.

"We're always worried about this in terms of chaos. It's going in the right direction so far but I'm not sure it will carry on like this. I don't know," he said from his London base.

Meanwhile, Zahi Hawass, Egypt's antiquities chief who became a cabinet member this January, posted on his blog a list of some two dozen sites that were looted or vandalized since the uprising that led to the fall of Hosni Mubarak.

"Our antiquities are in grave danger from criminals trying to take advantage of the current situation," he writes.

Among the looted and vandalized sites were the storerooms for the Metropolitan Museum of Art's excavation site in Dahshur, south of Cairo, as well as the looting of the tomb of Impy near the Great Sphinx at Giza.

Hawass told the New York Times on Thursday that, for political reasons, he would not accept a post in the new Egyptian government to be formed by Essam Sharaf following the resignation of prime minister Ahmed Shafiq.

The depature of Hawass could lead to even more looting, Karl von Habsburg, president of Association of National Committees of the Blue Shield, a body that tries to protect cultural heritage in conflict zones, told the paper.

"I am terrified by the idea that [Zawass's departure] might be a sign to potential looters that now that last element of control is gone, and now we have a free hand to continue looting," he said.

Elke Rogersdotter / Univ. of Gothenburg

Play was an important part of people's everyday lives at Mohenjo-Daro in Indus Valley 4,000 years ago.

Games of leisure played a key part of life 4,000 years ago in the Indus Valley of present-day Pakistan, according to an archaeologist at the University of Gothenburg in Sweden who found that dice and other game pieces make up nearly 10 percent of the artifacts recovered in the ancient city of Mohenjo-Daro.

Archaeologists often recover play-related artifacts, but usually dismiss them as unimportant for research or regard them as ritual objects or signs of social status, says Elke Rogersdotter, who studied the play-related artifacts for her doctoral thesis.

She argues that studying play can give archaeologists insight to the social structure of ancient societies. For example, at Mohenjo-Daro, not only is there an abundance of play-related objects, they also appear to follow a repetitive pattern of spatial distribution. This may indicate specific locations where games were played, such as gaming parlors.

"The marked quantity of play-related finds and the structured distribution shows that playing was already an important part of people's everyday lives more than 4,000 years ago," she said in a news release.

Cubical dice were the most widely found items, but archaeologists have also unearthed balls and marbles, conical gamesmen, "long dice" and casting bones — as well as what seem to be game boards made from bricks. Some experts have speculated that a game similar to ancient Mesopotamia's "Royal Game of Ur" was played at Mohenjo-Daro.   

Mohenjo-Daro is the largest urban settlement from the Bronze Age in the Indus Valley, a cultural complex of the same era as ancient Egypt and Mesopotamia. Archaeologists have found the site difficult to interpret because they haven't found remains of temples or palaces, which makes it difficult to determine how the settlement was managed and what distinguished the elite.

For more information, check out Rogersdotter's thesis, which has been successfully defended.