An 11-mound site in Louisiana predates other known mound complexes（「Poverty Point」のことです） with earthen enclosures in North America by 1900 years. Radiometric, luminescence, artifactual, geomorphic, and pedogenic data date the site to over 5000 calendar years before present. Evidence suggests that the site was occupied by hunter-gatherers who seasonally exploited aquatic resources and collected plant species that later became the first domesticates in eastern North America.

始期について
These dates suggest that mound construction at Watson Brake began between 5400 and 5300 calendar years B.P..

終期について
These conditions persisted until about 4800 calendar years B.P., when a diversion of the Arkansas River into the present course of the Ouachita River（ウォシタ川：今後頻出します） caused rapid alluviation near Watson Brake, decreasing the extent of the swamp and small-stream habitats. This event may coincide with abandonment of the site.

●Archaeology（Volume 51 Number 1, 1998年　1/2月合併号）　　　　　　　　　　　　　　　　　　　戻る

　"Earliest Mound Site" by Amélie A. Walker

Watson Brake, in the floodplain of the Ouachita River near Monroe in northern Louisiana, may be the oldest large-scale mound site in the Americas. It has been dated to 5400 B.P. (years before present), making it 1,900 years older than Poverty Point, a ceremonial and trading center in Louisiana which has been dated to 3500 B.P. and was long thought to be the earliest such site.

Consisting of at least 11 mounds from three to 25 feet tall connected by ridges to form an oval 853 feet across, Watson Brake was discovered by Reca Bamburg Jones, a local resident, more than 30 years ago after a timbering operation cleared the land. In addition to radiocarbon testing, the University of Texas at Austin and the University of Washington dated the mound from organic acids and sand grains in the soil.

The new investigation, led by Joe W. Saunders of Northeast Louisiana University, indicates that Watson Brake may have been used as a base by mobile hunter-gatherers from summer through fall. Located above wetlands, the site would have provided access to vast aquatic resources during certain seasons. Bones of the freshwater drum, a species of fish that spawns from spring to early summer, and charred seeds of plants that ripen in the summer and fall were recovered at the site. The findings contradict the commonly held belief that major building projects took place only in complex societies with permanent villages supported by agriculture or trade. Mobile hunter-gatherers, it was thought, were unable to undertake such projects.

The inhabitants of Poverty Point, while not yet agriculturalists, had a complex social organization, took part in extensive trading networks, and possibly maintained year-round occupation. There is no evidence of permanent occupation at Watson Brake, and its few beads, stone tools, and fired earthen blocks were made from local materials, indicating that it did not take part in trade.

The surfaces of the ridges and mounds show little evidence of occupation, leading archaeologists to believe that Watson Brake was occupied primarily before and during the building of the mounds. It is thought that the site was abandoned about 4,800 years ago after the Arkansas River changed course, drying up swamp and small-stream habitats, making the site less suitable for seasonal habitation by hunter-gatherers. Though the purpose of the mounds is unknown, it seems they were not used for burial or religious purposes, as no human remains or ceremonial objects have been found.

The southern half of the site is owned by the Archaeological Conservancy, while the rest is privately owned.

A Watson Brake mound; inset, fired earthen objects found at the site (Courtesy Joe W. Saunders)

　"Ouachita River Mounds: A Five Millennium Mystery" 　By Lori Tucker

In northeastern Louisiana, where the Louisiana Folklife Festival gathers "the tribes" today, hunters-and-gatherers established a tradition of moundbuilding that began five millennia ago and continued until the arrival of Europeans. The earthworks they built are striking evidence of Louisiana's earliest residents. They also are a testimony to the complexity of an ancient culture that remains largely a mystery.

What we understand about the moundbuilders is changing as a result of research in the last decade. Previously, researchers, influenced by modern studies of San hunter-gatherers in Africa, have assumed the small, mobile bands that inhabited the southeastern U.S. 5,000 years ago didn't have the social structure necessary for major earthworks. Now, research at numerous sites confirms that people who had not yet cultivated plants or learned how to make pottery had the engineering skills to build impressive earthworks as well as the ability to work together to complete labor-intensive projects.

The massive earthworks at Poverty Point near Epps were long considered the beginning of extensive mound construction. Non-native stones found on the site originated as far away as Wisconsin, Tennessee, and Georgia indicate that Poverty Point was a major trade center circa 1500 BC. The Poverty Point culture spread over a large part of the Lower Mississippi Valley and flourished from around 1730 BC to 1350 BC. Until recently, Poverty Point was considered an amazing anomaly because no one had identified significant earlier sites.

In the early 1990s, Joe Saunders began to test the theory that Poverty Point was the oldest mound complex. Saunders is regional archaeologist for the Division of Archaeology in the Louisiana Department of Culture, Recreation and Tourism. He obtained calibrated radiocarbon dates from several sites including Hedgepeth, Frenchman's Bend, and Watson Brake that placed their construction between 3700 BC and 3000 BC. Saunders and others now have reason to believe that mound construction was widespread by 3000 BC in northern and southern Louisiana as well as Mississippi and Florida where other researchers have worked for years. Reca Bamburg Jones was instrumental in bringing Watson Brake to Saunders' attention. She grew up near the mounds, located about 20 miles southwest of Monroe. Like other local residents, she always knew about the mounds, but only three were clearly identifiable in the thick woods. Jones made a mid-life decision to pursue archaeology in earnest as a hobby in the early 1980s. She enrolled in every archaeology course she could at the University of Louisiana at Monroe. In 1981, logging operations revealed more of the landscape at the mounds than before. Jones studied the site and was the first to decipher the pattern of 11 mounds connected by ridges that form a circle roughly 280 yards across. The largest one is a steep-sloped 25-foot tall mound that overlooks a low swampy area. In 1983, John Belmont and Jones published the site in a survey of prehistory in the Ouachita River Valley. By the time Jones showed the site to Saunders, it once again was mostly hidden by thick forest. Saunders enlisted Thurman Allen, a soil scientist with the USDA Natural Resources Conversation Service, to assist in determining the age of the site. When Allen obtained a core sample of the largest mound, he found advanced soil development. Saunders then decided the site was worth further study. Radiocarbon dating of Watson Brake places its construction in a 400-year period beginning at 3400 B.C. Watson Brake became a focal point of research into Middle Archaic mounds because it is larger, more securely dated and has been disturbed less than the others. In September, 1997, Saunders and an interdisciplinary team of scientists published their findings about Watson Brake in Science, presenting evidence that Middle Archaic hunter-gatherers constructed monumental architecture at Watson Brake and lived there on a seasonal basis.

Though many aspects of life for the ancient moundbuilders remain a mystery, Tom Eubanks, State Archaeologist with the Division of Archaeology, said a look at Louisiana today provides some insight. The wetlands and streamed valleys that provide a habitat for wild game sought by today's hunters also provided food for people long ago. From streams and rivers, they gathered mussels and snails for food. They also captured many of the same fish that Louisiana's sportsmen enjoy today, freshwater drum, white perch, largemouth bass, bream, and catfish. Though at Watson Brake the site's food remains are mostly aquatic, bones found in the midden show that people also ate deer, turkey, raccoon, opossum, squirrel, and rabbits. Though modern Louisiana residents savor crawfish, apparently the ancient moundbuilders did not. Eubanks said the first people entered the Lower Mississippi Valley about 10,000 BC. These Paleo-Indians lived in small nomadic groups that followed wild game and lived in temporary shelters made of branches, grass and hide. They left few artifacts in any one location that would survive the humid climate. Since the sea level was lower than today, some of the state's earliest sites probably are under water or buried by the alluvial soils along the rivers, Eubanks said.

By the occupation of the Poverty Point site, culture had changed dramatically. No other earthworks in Louisiana compare in size to Poverty Point, which covers more than a square mile. In its time, it was the largest set of earthworks in the Western Hemisphere. Earthen ridges form six semicircles, one inside the other, that are interrupted by five aisles radiating from a broad flat center. Robert Connolly, former Poverty Point station archaeologist, says it was long assumed that the plaza at Poverty Point was naturally flat and may have attracted people to build there. Connolly said archaeologists now know that what looks like a natural plaza was once a large gully that people filled up with garbage and dirt. The Poverty Point culture flourished for more than 1,000 years, but had virtually disappeared by 600 B.C. The reason for the decline isn't known, but Eubanks said after Poverty Point people lived in smaller, scattered communities. They continued to build mounds.

Tristam Kidder, associate professor of anthropology at Tulane University said the archaeological sites found along the Ouachita River are both typical of those found elsewhere in the southeastern United States and also unique. They are unique in that they are older, but the earlier sites are more or less similar to the rest of the southeast in general characteristics, Kidder said.

Later, regional differences, such as the style of design on pottery, are evident. After 500 BC, archaeological evidence shows that the people in the Ouachita River Valley had a different culture than those in the Mississippi and Red River valleys though they were connected by trade, Kidder said. The purpose of the earliest mounds remains a matter of speculation, but it's evident that over time their function changed. None of the mounds at Watson Brake or Poverty Point are considered burial mounds. By the time of the Marksville Culture in the second century BC, some of the mounds were used for burials. The development of the Marksville Culture was another cultural shift. People at the Marksville site in Avoyelles Parish used images on their pottery similar to those of the Hopewell culture in the Ohio Valley.

As the climate changed, people began to diversify their economies. In northwestern Louisiana, the ancestral Caddo Indians built their economy on corn. In South Louisiana, the ancestral Chitimacha developed fisheries. The latest shift in archaeologists' views on the advent of moundbuilding raises new questions about the people who lived off the rich resources of Louisiana in Middle Archaic times, but Saunders said he plans to leave many of those questions for others to answer. Saunders compares his role to that of a carpenter who frames a house and leaves the finishing to another carpenter whose skills are better suited for the detail work. He said it's time for people to look at the site from different views and angles than his own.

Eubanks said now that a group of sites have been recognized as older than Poverty Point, the state would like to develop Watson Brake as a state commemorative area. Poverty Point and Marksville already are state commemorative areas, open to the public with interpretative museums and programs and also with ongoing research. At this time, however, Watson Brake site is not open to the public. The Archaeological Conservancy purchased half of the site in 1996 and later sold it to the state in an effort to preserve it. The other half is privately owned. The master plan of the Office of State Parks is to develop a series of sites representing different times in prehistory. The Ancient Mounds Heritage Area and Trails Advisory Commission, created by the legislature in 1997, is charged with identifying representative sites for this purpose. It will take many generations of archaeologists and researchers from related disciplines to decipher the mysteries of Louisiana's moundbuilders.

This essay was originally published in the 2000 Louisiana Folklife Festival booklet. Lori Tucker is a staff writer for The News-Star in Monroe, Louisiana.

Analysis of 27 Radiocarbon Dates indicates that the site was initially occupied around 4000 BCE during the Archaic period. Mound construction began at approximately 3500 BCE, and continued for approximately 500 years. During that time period the mounds were enlarged in several stages. Excavations indicate that there was sufficient time between building episodes for midden deposits to accumulate on top of the mounds and ridges. Saunders et al. suggest that the building episodes at Watson Brake coincide with periods of unpredictable rainfall caused by El Nino-Southern Oscillation events, and therefore may represent "a communal response to new stresses of droughts and flooding that created a suddenly more unpredictable food base." The site appears to have been abandoned around 2800 BCE.

Watson Brake is considered the earliest mound complex in North America. It is the earliest dated, complex construction in the Americas. Watson Brake's dating is nearly 2,000 years before the better-known Poverty Point, previously thought to be the earliest mound site in the United States. The discovery and dating of Watson Brake demonstrated that the pre-agricultural, pre-ceramic, indigenous cultures within the territory of the present-day United States were much more complex than previously thought. Monuments mark the rise of social complexity world-wide. The earthen mounds of Eastern North America are linked to mankind's monument tradition. In the Americas, mound building started at an early date, well before the pyramids of Egypt were constructed.

Eight members of the Gentry family have owned most of the site since the 1950s. One member refuses to sell property to the state, so it is not available for public viewing. They have allowed archaeologists on site for research.

　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　
●The Japan Times（1997.9.20） 　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　戻る

　"Man-made mounds said oldest in North America"

WASHINGTON (AP)　 Low mounds built about 5,400 years ago on a river plain in what is now Louisiana are the oldest known human-built structures in North America, researchers have determined.
The mounds, at a place called Watson Brake, about 32 km southwest of Monroe, were built by a people who found food in nearby rivers and forests, and occupied the site over hundreds of years, according to Joe W. Saunders of Northeast Louisiana University.
Saunders, lead author of a study to be published Friday in the journal Science, said the people were seasonal hunters and gatherers who ate a lot of fish while living near a river for only a few months at a time.
Bones of catfish, drum and suckers, all common fish found even today in the rivers, were unearthed in the mounds. There was also evidence that the people feasted on turtles, mussels, aquatic snails and small animals.
It has long been believed that such hunters and gatherers lacked the organizational skills to build mounds, which are large humps that required digging up and moving huge amounts of earth, Saunders said.
"These mounds contain hundreds of tons of dirt and gravel," said Saunders. He said there are 11 mounds in a rough circle about 254 meters across. One of the mounds is over 6 meters high. The rest are 1 meter to 3 meters high. Many are connected by excavated ridges.
It was, said Saunders, a major project for people who had to move all of the material by hand.
Chemical dating of materials showed that construction of the mounds started about 5,400 years ago, making them about 1,900 years older than mounds found in Florida and elsewhere in Louisiana.
Just what the primitive people used the mounds for is still not known, said Saunders. He said it is unlikely the mounds were important for defense and they are too far from the river to be used as a refuge from floods.
"The Watson Brake mounds are preceramic," said Saunders. This means that the people living there had no vessels in which to cook.
Instead, he said, they apparently heated rocks and then dashed them with water to make steam. Saunders said his research team found large deposits of fire-cracked gravel, suggesting that the people used red-hot rocks to bake or steam their food.
Also found were large numbers of intact snail shells. This suggests, he said, that the people steamed the snails and then removed the flesh without breaking the shells.

On September 19, 1997, the New York Times announced the discovery of a group of earthen mounds in northeastern Louisiana. The site, known as Watson Brake, includes 11 mounds 26 feet high linked by low ridges into an oval 916 feet long. What is remarkable about this massive complex is that it was built around 3400 B.C., more than 3,000 years before the development of farming communities in eastern North America, by hunter-gatherers, at least partly mobile, who visited the site each spring and summer to fish, hunt, and collect freshwater mussels.

The Times（＝the New York Times、2項上に記事本文） was amazed. Watson Brake, it wrote, "challenges traditional ideas about early American cultures and suggests that pre-agricultural, pre-ceramics hunting societies were more socially complex than previously thought." Most people think of hunter-gatherers as small bands of people roaming the landscape in search of food, incapable of such ambitious projects, but over the past two decades archaeologists have learned that many hunter-gatherers did the same things that only agricultural societies were supposed to have done. They built large buildings, had big settlements with permanent chiefs, developed elaborate artistic and technological traditions, made war, and managed their land to get as much food out of it as possible. In short, they were socially complex.

The discovery of complex hunter-gatherers, a kind of society and economy now virtually extinct, is one of the major archaeological advances of the last two decades. As a discovery it is not widely appreciated, but it shows us that the range of human social and economic organization was much greater in the past than we had once thought. And it forces us to rethink fundamental questions, such as why plants and animals were domesticated and why inequality developed in human society.

Earthen mounds at an ancient American Indian site in Louisiana have been found to be the earliest known remnants of human construction in the New World. The discovery challenges traditional ideas about early American cultures and suggests that pre-agriculture, pre-ceramic hunting societies were more socially complex than previously thought.

The mounds, begun about 5,400 years ago, predate other similar public architecture at Indian sites by nearly 2,000 years, archeologists said in a report being published today in the journal Science.

The new findings could transform thinking about the progression of economic and social development in ancient societies, especially about the nature and abilities of bands of hunter-gatherers who once inhabited the Mississippi and Ohio River Valleys. They show that agriculture, permanent settlements or wealth from trade were not necessary conditions for the mobilization of labor for ambitious construction projects.

''It's a rare and wonderful case where one piece of research fundamentally changes our whole picture of early American life,'' said Dr. Vincas Steponaitis, an archeologist at the University of North Carolina at Chapel Hill who is president of the Society of American Archaeology and an authority on Indian mounds.

MONROE, La. (AP) The Indian mounds deep in the northeast corner of Louisiana don't look like much. Two guys with a backhoe and bulldozer might have needed a day or so to shove dirt into that oval of mounds and ridges.

Until a timber company clear-cut the trees and thickets at Watson Brake in 1981, nobody even realized they had been built to create a greater shape. And it took nearly two decades after that to discover that they are the oldest known grouping of mounds in the Western Hemisphere.

They might not have survived without the dogged crusade of a former Census Bureau worker and amateur archaeologist named Reca Jones.

The mounds and their purpose are a mystery, but they have become a touchstone for archaeologists studying the Middle Archaic period ― around 6000 to 3000 B.C.

Work started a millennium before Tutankhamen was born. The much larger concentric series of earthworks about 100 km away at Poverty Point would not be built for 1,500 to 2,000 years. The Mayan pyramids in Central America and the Anasazi cliff dwellings in the American West were even further in the future.

"Many people thought the Middle Archaic was people running around doing hunter-gathering things for 3,000 years," said Mark Barnes, a National Park Service archaeologist. "They were much more sophisticated than we thought."

Jones had known since she was a child that there were a couple of old Indian mounds there.

Then Willamette Industries Inc., which owned half the site until the Archaeological Conservancy bought it in 1996, cut the trees. Suddenly Jones could see that there were more mounds than she had realized, with ridges connecting them into a giant egg shape. It was about 300 meters from end to end and 200 meters across.

"I was here almost the whole time Willamette was here, saying, 'Don't get on the mounds! Don't get on the mounds!'" Jones said. Willamette complied.

Then she asked a Harvard archaeologist to map the site with her, but he was interested in the ceramic age which began about 3,000 years ago. It wasn't until July 1993 that Joe Saunders, the state's archaeologist for that region, drilled the first sample.

Bit by bit, the evidence added up. The find went public last year, in Science magazine.

Jones' discovery, her years of work to get a professional to excavate it, and her work in the excavation and reconstruction won her the Society of American Archaeologists' Crabtree award for amateur archaeology.

Scientists have dated the remains to 5,400 years ago. But many questions may never be answered. For one, why were the mounds built?

Some of the oldest Indian mounds seem to be trash heaps covered with dirt. Here, sometimes the builders covered an area where they had lived and worked, camped on the new surface, then covered it over again. But others are just dirt on dirt. And all of the work appears to have begun at about the same time.

About 60 percent of the oval is a natural ridge that once overlooked swamp and a tributary of the Arkansas River. But why build it higher, and why close in the rest?

It probably wasn't flood protection; the land already was well above flood level.

The oval encloses nearly 9 hectares. But there's no sign that anyone lived in most of that space, aside from three small natural rises. There's no indications that the earthworks were a defense.

Poverty Point seems to have been a trading center. But everything at Watson Brake, 300 km northwest of New Orleans, is local. There's no sign of trade.

The trash included bits of charred grain, but they weren't cultivated. The mounds and ridges weren't farmed.

"Perhaps we ask the wrong question. Perhaps constructing the mounds was the purpose," Saunders said.

What can be verified? Bones and shells reveal that the mound builders ate lots of fish, mussels and aquatic snails, and some turtles and small animals. The leftovers also indicate that the people came in the spring and left in the fall.

Diggers have found scores of the flint drills, each about half a centimeter long, used to make beads.

Before Saunders and Jones began their work, the intricate earthworks at Poverty Point were the oldest known mound complex in North America. Construction began there in roughly 1500 B.C.

The builders at Watson Brake lived thousands of years earlier. Ninety-five percent of what they left behind is rock that was probably used for cooking, as it is cracked from the heat.

Only a few fragments of human bones have been found. But bones found in other areas indicate that the builders were probably about 160 cm tall. The smallest mounds were about chest-high to them, the biggest as tall as two-story buildings.

Excavation and reconstruction won't be the end of work here.

The state wants to buy the northern half of the site and establish a state park. The Archaeological Conservancy bought the southern 32 hectares in 1996, and sold it last year to the state.

The long-term hope is for a series of sites, one for each period - a prehistoric trail through Louisiana.

RECA JONES, who won an award from the Society of American Archaeologists for her work on the Watson Brake Indian mounds, walks to the base of a mound this spring near Monroe, La. The purpose of the 5,400-year-old mounds remains a mystery, but they have become a touchstone for archaeologists.AP PHOTO

　Throughout her life, Reca Jones wandered the mounds near her home in the small community of Watson, in the northeast corner of Louisiana near Monroe. She knew that the mounds were special, and she spent hours walking them and collecting artifacts: blocks of clay, round beads, and fire-cracked rocks. Afteｒ her marriage, ｓhe brought her young children to the mounds and tried to figure out their mystery.
　In the brake (a low area covered by water during the rainy season but mostly dry during the dry season) near Watson there are even mounds built in an oval shape connected by ridges. The oval encloses an area the size of three football fields. The tallest mound is about thirty feet, the size of ａ two-story building, and the smallest is only three feet high. Reca was convinced that these earthworks were man-made, but no one believed her.
　One day, when ａ timber company ａrrived to clear-cut the trees, Reca begged them not to bulldoze the mounds. They complied bｕt、in cutting down the trees, they exposed the egg-shaped mounds. Everyone could then see they ｗere purposefully made by human hands.
　Reca decided to learn more about prehistoric culture and enrolled in college to pursue a degree. She eventually enlisted the help of professional archaeologists who were able to verify that the circle of eleven little hills is indeed the oldest earthworks in North America. At 5,400 years old, they are older than the pyramids in Ｅｇｙpt､the Mayan step pyramids in Mexico, the mounds at Poverty
Point in northeast Louisiana, and the cliff dwellings of the Anasazi in the American West. They are reminiscent of the many standing stone circles in Western Europe, of which Stonehenge is the most famous.
　For her persistence and protection and investigation of the mounds at Watson Brake, Reca Jones was awarded the Society for American Archaeology's Crabtree Award for amateur archaeology. She still visits the mounds often and dreams of the lives of the ancient people who lived there so long ago.

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