NEWSFOCUS 4000 B.C.E. 3000 B.C.E. 2000 B.C.E. 6000–3000 B.C.E.: 3000–1000 B.C.E.: MIDDLE ARCHAIC LATE ARCHAIC

3500–2500 B.C.E. Watson Brake/Frenchman’s Bend/ Hedgepeth Mounds

About 1400 B.C.E. Watson Brake Poverty Point’s Birdman Mound built

festival, he adds. Because Cahokia appeared settlements were extensive and likely per- The big bang to lack vibrant trade, division of labor, and manent. In the July issue of the Journal of The gatherings at Cahokia began around a clear hierarchy, and because there are no Archaeological Sciences, Kelly, Brown, and 1000 C.E., when the American Bottom began written records and few burials, many con- colleagues describe eight copper nuggets to draw people from all over the region, sidered it an elaborate seasonal encampment found on one small Cahokia mound. They according to radiocarbon and ceramic dat- rather than a true urban area. conclude that Cahokians crafted copper ing. Pauketat and Kelly both argue that But more recent excavations, such as sheets by repeatedly heating the metal over mound alignments reinforce the idea of sea- Emerson’s current project in East St. Louis an open wood fi re and hammering it, then sonal ceremonies as a key part of the draw. and work in Cahokia by Kelly and archae- cutting it into shapes. Kelly says drinking Some mounds line up with the position of ologist James Brown of Northwestern Uni- cups found nearby, associated with hunter the sun at the winter solstice dawn, while versity in Evanston, Illinois, show that the and warrior rituals, suggest this was a com- others are oriented to its position at the equi- area was busy throughout the year, and that bination workshop and men’s club. noxes. The researchers speculate that a rash on March 12, 2012

Does North America Hold the Roots of Mesoamerican Civilization?

MONROE, LOUISIANA—High pyramids and great plazas are the hallmarks 9 hectares, back to 3500 B.C.E. On the ridges at Watson Brake, Saunders of ancient Mesoamerica, from the 3000-year-old Olmec cities along the Gulf uncovered huge amounts of fi re-cracked rock used for cooking in this pre- of Mexico to the inland metropolis of Tenochtitlan encountered by the Spanish pottery culture. “The abundance of food was unbelievable,” he says of the conquistadors. Yet the oldest examples that call to mind this familiar style are massive quantities of game and fi sh bones left behind. www.sciencemag.org found nearly 1000 kilometers to the north in the muddy bayous of Louisiana. Saunders’s 1997 paper (Science, 19 September, p. 1796) provided stun- Five millennia ago, Native Americans here began to build high mounds of earth ning evidence of a mound-building culture far earlier than previously sus- fl anked by fl at plazas that resemble Mesoamerica’s classic architecture. A small pected. “There were 2000 years of mound building in the southeastern U.S.” band of archaeologists suspect that these ancient settlements laid the founda- before the fi rst monumental architecture appears in Mesoamerica, says archae- tion not only for the North American mound-building tradition that eventually ologist David Anderson of the University of Tennessee, Knoxville. Saunders culminated in the great city of Cahokia (see main text, p. 1618), but perhaps argues that from about 3700 B.C.E. to 2700 B.C.E., Native Americans went on also for Mesoamerican civilization. a building spree across the lower Mississippi Valley, leaving behind mysterious The conical mounds dotting the lower Mississippi Valley were long consid- rectangular blocks of heated clay, thousands of spear points, and giant mounds. Downloaded from ered to be no older than 1000 years or so. But archaeologists in the 1970s and At Watson Brake, Saunders thinks periodic fl oods may have prompted inhabit- ’80s were puzzled by radiocarbon dates from some sites matching the Mid- ants to create the mounds as platforms for living and ceremonial use. He and dle Archaic period—which ended at about 3000 B.C.E. others have found little sign of extensive trade and sug- That’s nearly 2 millennia before the fi rst cities appeared gest that the mounds were not part of a closely connected in Mexico, before the Giza pyramids, and about the same culture, but rather a feature that each group may have time that the world’s fi rst major urban centers evolved used and interpreted differently. in ancient Mesopotamia. Most researchers dismissed the In the decade and a half since that key paper, a dozen dates as erroneous. other Middle Archaic mounds have been identifi ed. But But in the 1990s, Louisiana state archaeologist Joseph Saunders and other archaeologists say that more excava- Saunders began a careful study of the mounds, some of tion and precise redating are critical. which still rise as high as 10 meters. On a wooded site beside Instead, however, the state of Louisiana is focusing a bayou west of Monroe, he examined a six-mound site its limited resources on winning World Heritage status called Hedgepeth that includes a conical earthen structure for Poverty Point, the premier settlement during the sec- 8 meters high and some 33 meters in diameter—and ond great burst of mound building, which began about was radiocarbon dated to approximately 3000 B.C.E. 1600 B.C.E. and lasted for nearly 600 years. Located on Another site called Frenchman’s Bend, north of Mon- a bayou east of Monroe, the site includes a giant mound roe, proved to be of a similar age and boasted three lay- second only to that at Cahokia in size. Shaped like a fl ying ers of house fl oors and hearths as well as a half-dozen Solo seeker. With little support, Joseph bird—an image repeated in the region for 3 millennia— mounds. Radiocarbon dates put Watson Brake south of Saunders has pioneered work on Middle the structure rises 22 meters high, is 200 meters long,

Monroe, with its vast complex of 11 mounds encircling Archaic mounds. and contains the equivalent of 27 million baskets of OF SOUTHEASTERN ARCHEOLOGICAL CENTER, PATE/WWW.PATEART.COM/COURTESY BY MARTIN CREDITS TO BOTTOM): JOSEPH SAUNDERS; (TOP PAINTING RICKETT HISTORIC SITE, LA;ROBERT POINT MOUNDS STATE NPS,AND POVERTY

1620 23 DECEMBER 2011 VOL 334 SCIENCE www.sciencemag.org Published by AAAS 1 C.E. 1 C.E. 1000 C.E. 2000 C.E. 1000 B.C.E. 1000 B.C.E.–1 C.E.: 1 C.E.–500 C.E.: 500 C.E.–1000 C.E.: 1000–1500 C.E.: EARLY WOODLAND MIDDLE WOODLAND LATE WOODLAND MISSISSIPPIAN CULTURE

1600–600 B.C.E. 200 B.C.E.– 400 C.E. 1000– 1492 C.E.– Europeans Poverty Point Hopewell culture in Ohio 1200 C.E. arrive in North Cahokia America rise 1300 C.E.– Cahokia falls 1200 C.E.– East St. Louis burns; palisade at Cahokia 1100 C.E.– Monks Mound built

of surprising astronomical events, such as was completely abandoned. The short time Back at Monks Mound, scientists are Halley’s Comet of 989 C.E. followed by the span provides a rare window into the moment reconsidering their old assumption that the supernova of 1006 C.E., may have sparked a Mississippian culture began to organize in a massive project, which required moving religious and political movement in a culture more complex way. So far, Barrier’s as-yet- 6 million baskets of dirt (assuming 1 cubic that kept close watch on the sky. unpublished work shows that rather than foot of earth per basket), took generations to Seeking clues to that spark, University construct a traditional village of simple rectan- complete. After 2007 excavations, Timothy of Michigan, Ann Arbor, anthropologist gular huts, the 100 to 200 inhabitants created Schilling, now an archaeologist at the Univer- Casey Barrier is excavating an 8.2-square- a massive plaza and three mounds on virgin sity of Indiana, Bloomington, found little evi- hectare cornfield close to the Mississippi land. They also built 40 or so houses, some dence of erosion or organic matter collection River 64 kilometers south of Cahokia. Radio- with courtyards. But they abandoned them all at the mound, as would be expected in long- carbon and ceramic dating put the complex within a generation or two—possibly, he says, term construction. Based on radiocarbon dat- between 1000 and 1050 C.E., after which it to join the growing crowds at Cahokia. ing, he concludes that the mound took fewer on March 12, 2012

earth. The mound is at the apex of a remark- Land of plenty. Poverty Point residents valued able C-shaped complex spanning three hectares exotic materials, like the imported stone in and including six half-rings and a host of smaller these fi gurines. conical and fl at-topped earthworks (see image, www.sciencemag.org p. 1620). Most radiocarbon dates put construc- Provo, Utah. By examining the alignments of tion between 1400 and 1200 B.C.E. Archaic mounds, retired civil engineer Robert Unlike the Middle Archaic sites, which show Patten argued at a recent conference on little sign of long-distance trade, Poverty Point archaeo-astronomy that the numbers associ- was practically a trade fair. Along with more than ated with the sites are mirrored in later Meso- 8000 spear points, archaeologists have found american calendars as well as in the design of red jasper, quartz, and copper from as far as the Great Lakes, chert from near structures. The origin of the Mesoamerican system “should be searched for in a St. Louis, plus more than 130 clay fi gurines and innumerable bone awls likely vast area between the Mississippi River Basin and Mesoamerica,” he says. Clark Downloaded from used to puncture animal hides. “Poverty Point is vacuuming in materials in agrees: “We need to look to Louisiana as a source.” quantities that continue to stagger me,” says archaeologist Tristram R. Kidder Mesoamericans may have used the plaza-and-pyramid innovation to help of Washington University in St. Louis, Missouri. He has worked at the site since create a more complex social organization and to jump-start urban life. But in the 1990s and in 2009 published a report summarizing recent fi eld seasons. the Mississippi River valley, this didn’t happen. The second period of mound What was exported from Poverty Point is a mystery, however. Only a few stone building came to a halt by 1000 B.C.E., when Kidder says abrupt changes in beads that may have been manufactured there have been found in elsewhere. economy and society took place across eastern North America. Recent geo- Baskets, salt, and other possible exports may have left no trace. archaeological research in northeast Louisiana suggests large-scale fl oods As at Cahokia, Kidder and Timothy Schilling of the University of Indiana, and river instability, along with cooler temperatures. Flooding may have ren- Bloomington, discovered that the Bird Mound may have been built quickly, dered sites like Poverty Point uninhabitable. Coring in the Gulf of Mexico has perhaps in less than a year. The 2009 report on the mound notes that sediment lately confi rmed that large fl oods, some episodes extending over decades, on the bottom was squeezed up into upper layers, and there are no microscopic dumped enormous quantities of sediment into the gulf for half a millennium, signs of worm burrows or raindrops, which would have left traces if the mound Kidder adds. had been built in stages. The Bird Mound complex is not matched at other sites For several hundred years, there were no mounds built. Finally in the early from the era; Mesoamerica at that period lacked monumental structures alto- centuries C.E., the third and fi nal period of mound building began, this time gether. “It’s unique,” says Kidder, noting that the mound predates Olmec pyra- centered in the Ohio River valley and culminating in Cahokia. mids and plazas by a couple of centuries. Explaining the construction gaps is a daunting challenge. But archaeolo- Did the Middle Archaic mounds and Poverty Point infl uence the rise of gists say the older mounds could provide a key to understanding New World Mesoamerican civilization? The question tantalizes archaeologists. The propor- development—if a new generation of researchers focuses on these largely tions used at the Louisiana sites closely match those found in Mesoamerica, obscure sites. “It’s very exciting,” Anderson says. “This is changing our whole

CREDITS (TOP TO BOTTOM): JENNY ELLERBE/COURTESY OF THE STATE OF LOUISIANA; WIKIMEDIA COMMONS; COURTESY SMITHSONIAN NATIONAL MUSEUM NATIONAL SMITHSONIAN COURTESY COMMONS; WIKIMEDIA LOUISIANA; OF STATE THE OF ELLERBE/COURTESY JENNY BOTTOM): TO (TOP CREDITS BOSTROM/LITHICCASTINGLAB.COM PETE HISTORY; NATURAL OF notes John Clark, a Mesoamerican specialist at Brigham Young University in picture of the region across a vast time span.” –A.L.

www.sciencemag.org SCIENCE VOL 334 23 DECEMBER 2011 1621 Published by AAAS