August 24, 2016

Monkeys in the Amazon rain forest likely entered their own Stone Age more than 700 years ago, according to scientists investigating a fascinating site at Serra da Capivara National Park in northeastern Brazil. At the site, scientists from the University of Oxford in the United Kingdom and from Brazil’s University of São Paulo observed bearded capuchin monkeys (Sapajus libidinosus) using rocks as hammers to crush hard-shelled nuts atop flat stone anvils. The scientists discovered dozens of discarded stone hammers and anvils once they began shallow excavations at a site regularly visited by the monkeys. The scientists determined that monkeys have been using simple stone tools at that site for more than 700 years. The findings were described in the July 2016 issue of the journal Current Biology.

A capuchin monkey uses stones to crack a cashew nut in Serra da Capivara National Park in northeast Brazil. Credit: © Michael Haslam, Primate Archaeology Project/University of Oxford

Stone Age is a term used to designate the period when prehistoric people used stone, rather than metal, tools. For humans, the Stone Age began about 3.3 million years ago, when small stones were first made into crude chopping tools by prehuman ancestors called Australopithecines. It ended in the Near East about 3000 B.C., when bronze replaced stone as the chief material from which tools were made.

In dry northeastern Brazil, hard-shelled fruits and seeds are more common than the fruit and succulent leaves that capuchins prefer. Centuries ago, a clever capuchin figured out how to pound open a nut using a heavy stone as a hammer on a heavier flat stone anvil, thereby opening up an entirely new and abundant source of food. The scientists observed that the monkeys will carefully select hammer stones and bring them to trees bearing nuts and fruits. The monkeys then stash the stones in hidden spots around the trees for later use. The research site in Brazil is littered with such stones that have accumulated over centuries.

For many years, scientists considered humans to be the only species that made extensive use of tools. In the 1960’s, however, naturalist Jane Goodall discovered that wild chimpanzees in Africa make and use simple tools. Goodall observed them stripping tree twigs and using the twigs as tools for catching termites. She also observed chimpanzees using rocks to break open hard-shelled palm nuts in the forest.

Earlier in 2016, some of the scientists involved in the Brazil research published observations of monkeys called macaques using stones to break open shellfish and nuts in Thailand. Now, with the Brazilian study, there seems little doubt that some species of nonhuman primates have long since entered their own Stone Age. The site in Brazil provides scientists with a unique opportunity to study the ecological, social, and cognitive (mental) factors that likely played a role in the development of technology and culture millions of years ago at the dawn of humankind.

August 5, 2014.

European scientists were surprised to find that the preserved and frozen body of a Stone Age man showed evidence of what is normally thought to be a very modern malady—cardiovascular disease. This discovery, by Albert Zink from the European Academy of Bolzano, Italy, resulted from his studies of the Iceman, nicknamed Ötzi, who was discovered in the Italian Alps in 1991. Zink’s findings suggest that cardiovascular disease may not be just the unfortunate by-product of our modern diet and couch-potato lifestyle, but may have plagued humankind since ancient times.

Hikers found the preserved and frozen body of a Stone Age man in the Italian Alps, near the border with Austria, in 1991. A recent medical examination of the Iceman's body revealed that he suffered from the modern malady of cardiovascular disease.

Ötzi was discovered by hikers in an area called Otztaler, which lies east of the Inn River along the borders of Italy and Austria. At first, authorities believed the body was the victim of a crime or an accident. After closer examination, however, they discovered the body was actually more than 5,000 years old. This discovery has provided archaeologists and other scientists with many insights into life in prehistoric Europe before the Bronze Age. Scientists have learned many things by examining the preserved body of the Iceman and the remains of clothing and tools that were found with him.

Initial medical examination revealed that Ötzi likely suffered from joint pain, Lyme disease, and tooth decay. But computed tomography (CT) scanning also revealed calcium buildups, a sign of atherosclerosis—narrowing of the arteries from fatty deposits, in several major blood vessels, including the aorta (the main blood-carrying vessel from the heart) and the carotid arteries of the neck. The advanced degree of cardiovascular disease present was surprising since Ötzi certainly had a physically active lifestyle and a diet absent the heart-harming high-fat processed foods and added sugars typical of modern civilization.

A more detailed study of Ötzi’s genome revealed that he possessed several gene variations that medical researchers know to be associated with cardiovascular disease. These small genetic variations, called single nucleotide polymorphisms (SNP’s), do not cause diseases themselves. However, patterns of SNP’s can help determine if a person’s genetic makeup predisposes that person to develop a particular disease. One particular SNP that Ötzi possessed on the ninth chromosome is strongly correlated with the development of heart disease.

Such finding explain how a Stone Age man could have suffered from such a modern malady as atherosclerosis. The finding also suggest that many people today may develop cardiovascular disease in spite of a healthy diet and lifestyle because, like Ötzi, they are genetically predisposed to the condition.

Additional World Book articles:

Archaeology 2001 (a Back in Time article)

Tales from the Crypt (a special report)

January 9, 2014

Some of the earliest evidence of severe tooth decay and bad breath in a population of prehistoric hunters and gatherers has been recovered by a team of British scientists from a cave in Morocco. The team, led by paleoanthropologist Louise Humphrey of the British Museum of Natural History in London, examined the skeletal remains of at least 52 individuals found in a North African cave known as the Grotte des Pigeons (Cave of the Pigeons). The remains date from 13,700 to about 15,000 years ago. The scientists found evidence of tooth decay in all but three of the individuals and severe tooth decay in about half. The evidence of decay in some of the individuals was so severe that the people were likely suffering from constant discomfort or pain. The hunters also almost certainly suffered from severe halitosis (bad breath) due to the rotten condition of their mouths.

The poor oral health of the Grotte des Pigeons population surprised the scientists. Prehistorians can usually identify hunter-gatherer populations in the archaeological record simply by examining their teeth. The teeth of these people are often in excellent condition, and tooth decay, periodontis (gum disease), or dental caries (cavities) are rarely seen.  Early farming communities are equally easily identified by the amazingly poor oral health seen in their remains.

Before agriculture was developed about 12,000 years ago in the Middle East, Stone Age peoples survived by hunting game and gathering wild plant foods. Such foods are low in simple carbohydrates (sugars) that cause tooth decay and dental caries that plague modern agricultural societies. Once people began cultivating wheat, barley, and rice, they began preparing the grains into soft, gummy, carbohydrate-rich foods, including bread, porridge, and beer. Bacteria in the mouth digest the simple sugars from such foods and release acid that breaks down tooth enamel, causing decay and caries. Modern advances in dental care, including brushing, flossing, and fluoridation, have done much to improve oral health. But nearly all people in modern societies still suffer from tooth decay, gum disease, and caries due to a grain-based diet rich in the simple sugars that oral bacteria thrive on.

Sweet acorns are produced by certain oak trees, including the cork oak, which grows in northern Morocco, western Spain, and Portugal. The acorns are still prized today. (World Book illustration by Chris Skilton)

The scientists linked the prehistoric hunters’ dental woes to a large amount of sweet acorns found in a nearby refuse pile that contained the remains of wild plant foods the people of Grotte des Pigeons consumed. The people most likely boiled the sweet acorns and ground them up to make a sticky flour. Although they never cultivated any crops, the diet of the Grotte des Pigeons people was more similar to a modern agricultural population, rich in sticky, decay-causing, carbohydrates from wild sources. Although the population appears to have been robust and well-fed, the pain in their jaws and bad breath almost certainly made life miserable for all. Unfortunately for the Grotte des Pigeons residents, the evidence for dentistry in the archaeological record does not appear until about 6,500 years ago.

Additional World Book articles:

• Dental hygiene
• Controlling the Causes of Bad Breath (a Special Report)
• Healthy Gums

August 8, 2013

The discovery of charred remains from two Neolithic longhouses that likely served as “Halls of the Dead” for ancient Britons nearly 6,000 years ago have been reported by archaeologists in the United Kingdom. The wooden remains were uncovered within two barrows (earthen mounds) excavated at Dorstone Hill, near Hereford, by archaeologists from the University of Manchester and the Hereford Council. The longhouses were used by Neolithic people to house the bodies of high-status people. Archaeologists believe that such structures were revered because ancient Europeans believed that the household was as significant to the dead as it was to the living.

Ancient people in what is now the United Kingdom and Ireland constructed barrows from about 4000 B.C. until the start of Saxon rule, about A.D. 450 to 500. The oldest barrows date to the early Neolithic period, when the ancient Britons were starting to settle into small communities. The barrows at Dorstone Hill predate the construction of the massive complex at Stonehenge by about 1,000 years.

Upright stones surround a large barrow at West Kennet, in southern England. A barrow is a mound of earth, stone, or both built over an ancient burial place. Remains of barrows appear in many parts of the United Kingdom and Ireland. (© Alan King, Alamy Images)

Archaeologists discovered the two barrows at Dorstone Hill while surveying a field where ancient flint artifacts were found over many years. While excavating the two barrows, which are 230 feet (70 meters) and 98 feet (30 meters) in length, they discovered unusually well-preserved remains of the wooden longhouses. Much of the detail of the two longhouses could be seen from the pattern of charred timbers and stakes as well as postholes visible as patches of darkened earth. The remains revealed a pair of long buildings with aisles and internal partitions framed by upright posts that held up a wooden or thatch roof. Hard chunks of burnt clay scattered about indicated the walls of the longhouses were covered with a mud daub.

At the end of the smaller barrow, darkened earth showed a pattern of large upright posts surrounding a long trough that would have been lined with wooden planks. This structure was likely used as mortuary chamber, where the bodies of 30 to 70 people were held. The dead were usually buried in such chambers long after all the flesh had rotted away.

Archaeologists believe the longhouses were deliberately burned down after some time and the ashes were used to construct the earthen barrows. The halls were most likely burned after some critical event occurred, such as when the head of an important family died. But no human remains have been preserved in the acidic soils of Dorstone Hill. The barrow would have served as a reminder to future generations that an important person was buried at this location. The archaeologists found several fine flint blades buried in the barrows suggesting that people occasionally returned to the site to leave offerings for the dead.

Additional World Book articles:

• Arthur, King
• Celts
• Celtic art
• Druids
• England (History)