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REMNANTS OF THE PASTHigh-tech analyses of ancient textiles yield clues to cultures

BY DIANA PARSELL

In a museum lab, Irene Good is studying pieces ofsilk from long-lost cloth found at archaeologicalsites in western Europe and central and south Asia.The material at hand—short lengths of threadsthat were spun from the cocoons of moths—is

barely visible. Good immerses the threads in a solutionto tease apart the strands of protein. Then, she uses sev-eral methods of biochemical analysis to examine the proteins’ amino acids. What amino acids are present and theirorder vary for proteins from different species of moths and there-fore give a clue to the place where the silk was made.

“What I love most is being able, not just to alter what’s known,but to improve access to the past based on very tiny pieces of evi-dence,” Good says.

“Until recently, it was assumed that all [ancient] silk was fromChina,” says Good, a specialist in fiber analysis and ancient-textileproduction and trade at Harvard University’s Peabody Museum.Scholars held that silk dating from 2400to 700 B.C. was carried afar on traderoutes from China.

But Good’s work is now calling thatassumption into question. Her findingsindicate that the ancient silk came notfrom domesticated Chinese silkwormsbut from species of wild moths native towestern Europe and Asia.

“Now, it looks like some of the early silkindustry outside China was earlier thanthought and more widespread,” Good says.

Today, Good and other researchers areapplying high-tech methods of chemicalanalysis to ancient textiles and fibers toglean unique clues about past civiliza-tions. The results are shedding light onmany aspects of daily life among earlypeoples, such as their technological skillsand funeral customs.

Much of the insight is coming fromminuscule samples of textiles, whicharchaeologists categorize as “fiber perishables.” Until recently, theseremains were usually overlooked because they were frayed, discol-ored, or too fragile to withstand the rigors of analysis.

“Because textiles are organic, they’re subject to biological dete-rioration from air, water, minerals, insects, and fungi. All kinds ofthings attack organic material and use it as their dinner,” saysJoseph Lambert of Northwestern University in Evanston, Ill. Heis a pioneer in the use of analytical-chemical techniques for thestudy of archaeological materials.

Most cloth and other fiber goods degrade over time and even-tually disappear. In some cases, however, ancient textiles survived

well because they’d spent centuries in arid, freezing, or low-oxy-gen environments, such as well-sealed tombs.

Scientific interest in ancient textiles and other fiber objects is bur-geoning. “Today, we’re finally combining archaeological back-ground with training in [scientific] instrumentation to put it alltogether,” says Lambert.

SCRAPS OF EVIDENCE Chemical analysis and powerfulmicroscopy can reveal remarkable characteristics of textiles: whatplants and animals the fibers came from, how the yarns weremade, what weaving techniques were employed, and what dyesor pigments were used to color them.

Such information, combined with other evidence, enablesresearchers to infer the technological skills of early peoples and thecultural importance of their textiles, notes Kathryn Jakes of OhioState University in Columbus. “People had a particular intent whenthey were producing these textiles,” she notes.

Jakes, trained in polymer chemistry, has used advanced meth-ods of chemical analysis in her 2 decades of research on textiles ofearly Native Americans in central and eastern North America.

These groups, known collectively as theHopewell and Mississippi civilizations,inhabited the region extending fromFlorida to New York and westward to Wis-consin. They lasted from about 100 B.C.until encroachment by European explor-ers and settlers in the early 1500s. Indi-vidual groups had distinctive ways of life,but they shared many beliefs and practices,including elaborate cremation ceremoniesin which textiles played an important role.

Among the fabric samples Jakes has ana-lyzed are carbonized scraps from Hopewellburial sites, which were typically earthmounds. Charring during the cremationinhibited the growth of bacteria among thethreads and prevented total disintegrationof the remnants, she notes.

Jakes has found that textile patterns andstructures varied among Hopewell groups.“Although cremation rituals and burialsmay have been culturally dictated over a

wide geographic area, the textiles used in these rituals were locallyproduced,” she notes.

Analyses have revealed decorative patterns indicating that atleast some of the now-faded Hopewell-era textiles had been colored.“The presence of color reflects a significant level of technology,including knowledge of colorants in nature and of methods requiredto affix them to organic materials,” says Jakes.

She and her colleagues Amanda Thompson and Christel Bal-dia have conducted experiments to find out what combinations ofplants and minerals the Hopewell groups may have used to pro-duce various colors.

HOT CLUE — This scrap of charred fabricrecovered from a burial site reveals fiberstructure and other details.

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Prehistoric people probably used sumac and bedstraw as dyes,Jakes says, because caches of those seeds have been recovered fromarchaeological sites although the plants have no known dietary use.In one set of experiments, for example, the researchers made dyebaths from sumac berries and bedstraw roots combined with dif-ferent mineral fixatives. When the researchers tested the baths onfibers from milkweed plants and rabbit hair, only one combina-tion—sumac, bedstraw, and potassium carbonate—produced a deepred that was colorfast.

To estimate the time and skill that early Native Americans mayhave needed to make textiles, Jakes and her colleagues have donestudies replicating yarn production from different plant fibers. Inone experiment, several spinners were asked to produce yarnscomparable in quality to those of textileartifacts from a Mississippian-period sitein Carter County, Ga. The results demon-strated that a spindle technique was morethan twice as efficient as hand-spinningmethods. The spinning of cotton fiberswent much slower than that of flax orhemp because cotton fibers are short andrequire more twists per turn to holdtogether the fibers.

These findings and others indicate thatthe early natives of what is now the east-ern United States were highly skilled atcloth making, says Jakes, who presentedsome of her findings last August inPhiladelphia at a meeting of the AmericanChemical Society.

THREADS BARE ALL Many moderntechniques of analytical chemistry are wellsuited to the study of ancient textilesbecause they require only small samplesof material, Lambert notes. These tech-niques also enable researchers to investi-gate other organic materials that may havecome in contact with textiles.

Several years ago, James Adovasio andDavid Hyland of Mercyhurst College inErie, Pa., analyzed trace residues of bloodand other animal tissue on textile remnantsfound at a prehistoric Indian cemetery in Windover, Fla. To com-pare these residues with samples of deer and human tissue, theresearchers used a technique that relies on antibodies to identifyproteins. The results, Adovasio says, indicated that some of thehuman remains had been wrapped in deer hide as well as textiles.

Richard Evershed of the University of Bristol in England isanother pioneer in the chemical analysis of organic archaeologi-cal materials. In the Sept. 16 Nature, he and his colleagues describetheir study of cloth wrappings from animal mummies of ancientEgypt. The Egyptians preserved millions of mammals, birds, andreptiles as votive offerings. Scholars had assumed that ancient peo-ple used relatively simple and inexpensive methods to prepare thismultitude of animals for burial.

Evershed’s findings call that assumption into question. His teamcombined mass spectrometry with gas chromatography to analyzesamples from cat, hawk, and ibis mummies. The embalming sub-stances turned out to include fairly exotic materials, such as oils,beeswax, sugar gum, and tree resins, and were as complex as thoseused for human mummification. Evershed suggests that the ancientEgyptians had surprisingly sophisticated knowledge of how to usevarious preservatives.

DREAM WEAVERS The study of ancient textiles and otherorganic materials is a much-needed counterpoint to the traditionalarchaeological focus on objects made of stone, bone, metal, and

clay, says Penelope Drooker of the New York State Museum inAlbany. Evidence from tools and weapons can lead to skewed inter-pretations of past life, she says.

Until fairly recently in human history, Drooker points out, per-ishable goods comprised a large part of the materials of everydaylife. At some archaeological sites in western North America, forexample, an estimated 95 percent of recovered artifacts were madeof wood, bark, plant fiber, leather, fur, or feathers.

“It takes a conscious effort to reconstruct the richness of tradi-tional material culture,” says Drooker, a specialist in fiber-basedarchaeological objects found in the eastern United States. “There-fore, it is very important for archaeologists to pay attention to thefragments of perishable material culture that do survive.”

Much of Drooker’s research has focusedon impressions of ancient textiles left inclay and other once-malleable substances.She is currently studying what appear tobe markings of fine textiles etched in stonepalettes recovered from prehistoric bur-ial mounds. Native Americans may haveused the palettes to prepare pigment forvarious rituals, says Drooker.

As sophisticated techniques of analy-sis have revealed more-detailed informa-tion about ancient textiles, scholars havebeen rethinking ideas about the earlydevelopment of skills such as spinningand weaving. Fiber samples found incaves in France had convinced scientiststhat textile production first arose about15,000 years ago. Now, some scholarsassert that weaving and cloth makingdeveloped considerably earlier.

After examining early representationsof human clothing, Elizabeth Barber ofOccidental College in Los Angeles con-cluded that textile weaving is at least20,000 years ago. A specialist in theBronze Age and Neolithic cultures of theAegean and southeast Europe, she hasargued that fiber-making expertise was asrevolutionary as the creation of stone andmetal tools.

Learning to twist plant and animal fibers into stringlike yarnsenabled prehistoric people to weave nets, baskets, and other objectsthat eased the chores of everyday life, Barber explains in her exten-sive writings. As the tasks of providing food, clothing, and shelterwere divided between men and women in tribal societies, she says,women became the primary weavers because they could performthat activity while tending children.

Research by Adovasio and Olga Soffer of the University ofIllinois at Urbana-Champaign suggests even older origins forthe emergence of weaving skills. When these researchers ana-lyzed impressions in clay artifacts from the Czech Republic,some dating from 28,000 years ago, they concluded that thematerials bore the markings of cloth, nets, and baskets. Adova-sio and Soffer contend that ancient carved “Venus” figurinesfrom central and eastern Europe are depicted wearing wovencaps, skirts, and head coverings—evidence, they say, of sophis-ticated weaving skills among Ice Age people (SN: 10/21/00, p. 261). Other scholars disagree.

Adovasio, who has built an elaborate lab at Mercyhurst for thestudy of archaeological artifacts, continues seeking new ways toapply modern scientific tools to cloth remnants and other objectsfrom past cultures.

“There’s no practical end to what you can use modern analyticaltechnology for,” he says, “as long as you frame the research in sucha way that the technology can help you answer the question.”

BRIGHT INSIGHT — Differential interferencecontrast image of a butterfly weed stem (top)shows structural details of the plant fiber, andsimilar image of black willow stems (bottom)shows crystal inclusions that researchers useto identify the plant fiber.

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