Gourd and squash artifacts yield starch grainsof feasting foods from preceramic PeruNeil A. Duncan1, Deborah M. Pearsall, and Robert A. Benfer, Jr.

Department of Anthropology, University of Missouri, Columbia, MO 65211

Edited by Michael E. Moseley, University of Florida, Gainesville, FL, and approved June 8, 2009 (received for review March 26, 2009)

In a study of residues from gourd and squash artifacts, we recov-ered starch grains from manioc (Manihot esculenta), potato (Sola-num sp.), chili pepper (Capsicum spp.), arrowroot (Maranta arundi-nacea), and algarrobo (Prosopis sp.) from feasting contexts at theBuena Vista site, a central Peruvian preceramic site dating to �2200calendar years B.C. This study has implications for the study ofplant food use wherever gourds or squashes are preserved, doc-uments the earliest evidence for the consumption of algarrobo andarrowroot in Peru, and provides insights into foods consumed atfeasts.

An enhanced understanding of the use of bottle gourds inaceramic cultures through the examination of starch resi-

dues on the gourds’ interior surfaces provides us with a potentialpathway to understanding behavioral, economic, symbolic, andritual contexts in which these artifacts are found. The myriaduses for the shells of bottle gourd (Lagenaria siceraria) andsquash (Cucurbita sp.) in the archaeological record for both toolsand, for squash, food complicates determination of the preciseuse of these materials without direct contextual information,such as gourd fishing floats attached to nets (1), or encounteringwhole or partial gourd artifacts from which one can infer theiruse through ethnographic analogy (2). In this study, we extractedstarch from the residues of fragmented squash (Cucurbita) andgourd (L. siceraria) serving vessels deposited in a ritual contextat the Buena Vista site in central Peru, located �35 km inland(11°43�51.72�S, 76°58�5.45�W) from the mouth of the ChillonRiver (Fig. 1). Overlooking the valley floor, Buena Vista con-tains monumental late preceramic architecture. Its large, elab-orate, isolated space with uniquely patterned astronomical align-ments (3) suggest that it served as a small ceremonial center inthe central Chillon Valley. The starch residues of edible plantsfound on the artifacts and the special archaeological contextfrom which these artifacts were recovered suggest that theartifacts were used in a ritual setting for the serving andproduction of food. Among archaeologists, there is tremendousinterest in the examination of feasting, defined loosely as thesharing of food or drink in a special context or for a specialpurpose (4), in understanding the social relationships betweenemergent elites and commoners. The use of food, particularlychicha (maize beer), in traditional Andean systems in thematerialization of public labor is well documented (5, 6); how-ever, the prehistoric use of food in religious, social, or economicrituals in the Andes is less understood (7, 8).

Gourd and squash artifacts for this study were recovered froma central feature in the Fox Temple at Buena Vista, named afteran incised stylized drawing of a fox in the doorway. At the topof the temple mound, a large room (�15 � 7 m) contained anelevated platform within which there was a sunken niche-walledpit (Fig. 2 A and B) from which the materials in this study wererecovered. The temple was intentionally interred, as is consistentwith the ritual entombment of monumental architecture at otherAndean sites, particularly at Kotosh (9–11), which shares similararchitectural features with Buena Vista. The room itself wasfound clean of refuse, save for a single tree trunk lying adjacentto the platform in the center. Within the platform, the sunken pitcontained well-stratified and abundant food and other plant

remains, a few mussel shells, and some small fish remains.Abundant food remains, including seeds of chili peppers (Cap-sicum sp.), guava (Psidium guayaba), lucuma (Pouteria lucuma),and squashes (Cucurbita maxima, C. moschata, and C. ficifolia)and rind fragments of sweet potato (Ipomoea batatas), manioc(Manihot esculenta), and potato (Solanum sp.), were recoveredwith the remains of nonfood plants such as cotton (Gossypiumbarbadense), grass, fragments of agave leaves (Furcraea andina),and partially burnt twigs and charcoal. Faunal remains are muchless abundant and limited primarily to mussel shells and smallfish vertebrae. Charcoal from separate stratigraphic levels withinthe pit provided two radiocarbon dates, both �2200 calendaryears B.C. (Table 1), suggesting that the pit was filled in a shortperiod. The sequence of burial began with what might bedescribed as an ‘‘organic protective layer’’ similar to that de-scribed in the temple entombment at Huaca Soledad (12), a 5-to 10-cm-deep layer of grass and fine silt that covered the bottomof the pit, atop which commingled organics, grass, leaves, andfood remains were placed. Small round cobbles and graveltopped this layer, followed by more mixed organic material, thencapped with small angular gravel. The surrounding room wasthen filled with large rocks, some as large as 60 cm in diameter,to the level of the top of the platform. Last, the entire room wasfilled with shicra, cane bags filled with rock.

Archaeological starch grain research has contributed greatlyto the study of plant use and consumption by humans (13–15).However, this is the first study to analyze residue from bottlegourd or squash artifacts. One cannot underestimate the signif-icance of squash and bottle gourds to humans. Utilitarian bottlegourds and edible squashes are among the first cultivars in theAmericas (16, 17). On the Peruvian coast, bottle gourds arecommon in preceramic contexts and closely associated withmaritime subsistence as net floats (1). However, their use alsoenters the realm of the sacred as symbolic containers (18) andfor serving ritual libations. As demonstrated here, residueanalysis can help to determine use.

ResultsStarch grains were recovered from squash and gourd artifacts byemploying a method similar to that used to recover microfossilsfrom stone tools and ceramics (see SI Materials and Methods).First, the artifact is placed in a sonicating water bath to loosenand remove adhering residue, which is collected as Sediment 1.Then, the artifact’s interior surface is lightly brushed to removeany remaining residue, collected as Sediment 2. Starch grains arethen isolated from each of these sediments (Tables 2 and 3).

The artifacts in this study are well-preserved, desiccatedspecimens recovered under conditions of exceptional preserva-

Author contributions: N.A.D. and D.M.P. designed research; N.A.D. and R.A.B. performedresearch; D.M.P. contributed new reagents/analytic tools; N.A.D. analyzed data; and N.A.D.wrote the paper.

The authors declare no conflict of interest.

This article is a PNAS Direct Submission.

1To whom correspondence should be addressed. E-mail: neilduncan@mizzou.edu.

This article contains supporting information online at www.pnas.org/cgi/content/full/0903322106/DCSupplemental.

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tion (Fig. S1). Squash and gourd fragments can be distinguishedeasily by cross-section (19). One Cucurbita sp. fragment wasstudied and yielded several noncucurbit starch grains, indicatingthat Cucurbita fruits also were used as food containers or servingvessels (Table 2). Seven of the 10 artifacts yielded starch. Asexpected, we identified starch from the mesocarp of the artifactitself. There is no significant difference in the number ofCucurbitaceae starch grains between Sediment 1 (sonicated)and Sediment 2 (brushed) samples. However, non-Cucurbita-ceae starch grains occurred in a higher number in the Sediment1 samples. Thus, the non-Cucurbitaceae starch grains appear tooccur in greater concentration in the food residue adhering tothe outermost interior surface of the artifact’s surviving meso-carp. A strong case can be made that non-Cucurbitaceae eco-nomic starch grains in both Sediment 1 and Sediment 2 representresidues from artifact use and not transfer of starch from soilsadjacent to the artifacts (20). Analysis of soils in the sunken pit

produced only three transient starch grains, all from Level 200,above the levels containing the starch-bearing gourd and squashfragments (Table 1). Starch identifications were aided by acollection of �250 comparative neotropical starch specimensand regional starch reports and keys (13, 21–23). Given thepotential for variation within a taxon, multiple criteria must beused to identify an individual grain (24). Our identifications areconservative. We securely identified five taxa: M. esculenta(manioc), Solanum (potato), Maranta arundinacea (arrowroot),Prosopis (algarrobo), and Capsicum (chili pepper).

Manioc starch occurs on three artifacts. One grain (Fig. 3B)is a relatively large (28 �m in diameter) sphere with two basalfacets and a large stellate-shaped fissure. Grain size is in theupper range of domesticated manioc starch and likely too largeto be wild (25). Other hemisphere-shaped grains with two basalfacets are consistent with manioc but not diagnostic on theirown. Facet morphology is distinct from similar grains in Cucur-bitaceae and I. batatas (sweet potato); thus, they were identifiedas M. esculenta. Another grain identified as M. esculenta isspherical with a depressed linear fissure and a regular extinction

Fig. 1. Location of Buena Vista on the central coast of Peru. (Inset) Locationof Buena Vista in the Chillon Valley.

Fig. 2. The sunken pit and platform in the Fox Temple. (A) Photograph ofsunken pit facing east. (B) Stratigraphic profile of the pit contents from whichartifacts were studied.

Table 1. Artifacts and radiocarbon dated contexts

Artifact nos. Context Radiocarbon years B.P. Date in calendar years B.C.

02, 05, 07 Sunken Pit: Unit 10, Feature 1, Level 300 3,770 � 80 B.P. (GX-31276) 2460–1980 calibrated01, 03, 04, 08 Sunken Pit: Unit 10, Feature 1, Level 400 No date

Sunken Pit: Unit 10, Feature 1, Level 425 3,790 � 80 BP (GX-32177) 2470–2020 calibrated09, 10 Unit 10, Cuad 3, level 100 No date

Standard radiocarbon date from associated charcoal, 2� calibrated result.

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cross. This grain lacks basal facets; however, the type appearswith diagnostic grains and faceted hemispheres in comparativemanioc samples.

Manioc macroremains are widespread in coastal preceramiccontexts; however, manioc is believed to have been domesticatedin the southern Amazon (26–27). In Perry’s study (22), starchgrains from initial period and late precontact manioc specimensfrom coastal Peru lacked the distinguishing stellate fissure (13)characteristic of lowland Amazonian manioc starch. However,the large stellate fissure consistent with the lowland morphotypeis present in the Buena Vista assemblage. This grain possiblyrepresents an earlier imported Amazonian manioc variety thatwas subject to selection over time, eventually resulting in themorphotypes seen in later coastal assemblages. Alternatively,this starch grain represents an early lowland variety that ceasedto be cultivated or is not related to later coastal forms. Addi-tional manioc starch from early coastal contexts would help toclarify these issues.

A starch grain from Solanum (potato) tuber was identified(Fig. 3C). Potato has great significance to modern and ancientAndean populations. Potato macroremains and microfossils arereported from a number of contemporaneous sites throughoutPeru (28–30). Several potato species and many varieties are andhave been cultivated, and many wild forms exist (31). At thistime, we cannot identify this starch grain to a species.

Capsicum (chili pepper) is represented by a single flattenedlenticular starch grain with an indented base and a linear featurevisible in side view (Fig. 3D). The central linear feature is diagnosticof starches in this genus (15). Capsicum is reported widely from latepreceramic sites on the coast of Peru (32) and in the highlands (15)and present in macroremains at Buena Vista.

Two grains identified as M. arundinacea (arrowroot) occur ontwo gourd fragments (Fig. 3E). Despite its widespread and longrecord of use in the neotropics (26), arrowroot is underrepresentedin Peruvian contexts. The only other evidence for arrowroot in thecentral Andes comes from microfossils at Waynuna in the southernhighlands in contexts dating to 2050–1650 B.C. (28). At several

thousand meters above its natural range, the Waynuna arrowrootrepresents an imported cultivar. Likewise, wild Maranta is notknown from the coast of Peru, making the starch grains identifiedin this study highly unlikely to represent a wild form. With flood-plain irrigation, arrowroot could have been cultivated easily. Thus,the most parsimonious explanation for arrowroot starch on thesegourd artifacts is that it was grown near Buena Vista.

Starch identified as Prosopis (algarrobo) also occurs in the artifactresidue (Fig. 3F). Algarrobo starch has a unique appearance, unlikeanything else in our reference collection. The unusual lobed shapewith protuberances and a deeply depressed area at the hilum, alongwith a very irregular extinction cross, correspond closely with starchproduced in Prosopis. This type may be a genus-level indicator ofstarch produced in Prosopis pods. Prosopis consists of several closelyrelated and morphologically similar species with high hybridizationpotential; thus, there is considerable confusion in the botanical (33)and archaeological (34) literature regarding its identification. Cur-rently, the dominant Prosopis on the Peruvian coast is P. pallida,with P. chilensis in higher elevations of the south and P. juliflora inthe northwest (33). Each species produces similar sweet edible pods.Species similarities are reflected in the pod starch grains. Forexample, a systematic study showed that there are no differences instarch between P. chilensis and P. flexuosa (35). Algarrobo isubiquitous in pre-Colombian Peru, most often as wood for fuel orconstruction (30, 36) or more rarely for seeds and edible pods (34).A long history of algarrobo use occurs in Argentina, beginning10,000 years ago (35). In Peru, less is understood regarding pre-historic consumption of algarrobo pods, which are today groundinto flour to make a syrup, algarrobina, or for drinks, such asfermented chicha de algarrobo. To our knowledge, this studypresents the first microfossil evidence and earliest evidence ofalgarrobo consumption in Peru.

DiscussionFour of the 10 artifacts sampled yielded starch from multiple taxaother than Cucurbitaceae and provide clues to preceramic cuisine.Our sample size is small; however, in future research, patterns ofcooccurrence of taxa on gourd artifacts will help us to betterunderstand preferences for certain food combinations or certaincombinations limited to ritual use. Alternatively, the multiple taxaon the artifacts may represent repeated use of the containers in bothritual and secular contexts. Also, that the containers provideevidence of manioc and algarrobo, both of which can be fermentedinto alcoholic beverages, may be significant (33, 37). The possibilitythat these plants could have been used in the production of alcoholduring the preceramic should not be overlooked.

The presence of these artifacts along with plant foods in a specialcontext is highly consistent with an interpretation of feasting (4).

Table 2. Starch grain data from squash and gourd artifacts per sediment sample

Artifact no. 1 2* 3 4 5 6 7 8 9 10

Sediment no. 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2

Lagenaria siceraria 1 2 1 1 2 1 1 1Cucurbita sp. 4 3Capsicum sp. 1Manihot esculenta 1cf. Manihot esculenta 2 2Solanum sp. 1Maranta arundinacea 1 1Prosopis sp. 1 1Unidentified 1 1Unidentified root/tuber 1 1 1Total starch 0 1 8 3 2 3 4 3 3 0 2 2 1 1 0 0 0 0 0 0

Sediment 1 was removed from the artifact by sonicating water bath. Sediment 2 was removed by brushing the artifact’s interior surface.*Cucurbita sp. artifact. All others identified as Lagenaria siceraria.

Table 3. Summary of starch grain data from squashand gourd artifacts

Number of samples

Sample type Cucurbitaceae starch Other starch Total

Sediment 1 9 (27.3%) 11 (33.3%) 20Sediment 2 8 (24.2%) 5 (15.2%) 13Total 17 (51.2%) 16 (48.5%) 33

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Macroremain analysis is ongoing; however, the fragmentary re-mains of the plant material, including charred and uncharred wood,grass, and cotton seeds and fiber, particularly the preponderance ofnonedible parts of food plants and broken gourd and squash servingvessels found in the pit, are counterindicative of offerings butconsistent with the refuse of consumption. Common Andeanofferings of coca leaves are conspicuously absent. Therefore, thevegetal contents of the pit likely do not represent the originalintended function or symbolism of the pit, for astronomical obser-vation or for ritual offerings of liquid libations such as later ushnu(39). Rather, the remains are more likely to be the refuse fromfeasting associated with the ritual entombment of the temple. Ritualentombment of monumental architecture was practiced commonlyin the preceramic and later; however, its association with feastingas a ritual component or to organize and motivate labor, althoughancient, has been investigated only recently. For example, at thecontemporary site of Cerro Lampay (7) on the north central coast,multiple small scale construction events were preceded by feastingrituals hosted by informal leaders who lacked the social power toorganize large amounts of labor for more massive building events.Despite their large size and complexity, many monumental sitesconstructed in the preceramic could have been built by a small localpopulation organized by emergent leaders who used feasts as ritualand political tools in materializing labor.

At Buena Vista, feasting event(s) before the entombment of theFox Temple likely served both political and ritual functions. Polit-ically, leaders could have used feasting as a means to cultivate andmaintain social relationships, whereby labor would be mobilizedtoward a communal goal, not unlike in later periods, where feastinginvolving maize beer helped to mobilize labor to maintain canals inthe Andes (6). Ritually, feasting before the temple’s entombmentmay have served also as a symbolic act toward canceling the originalfunction of the temple, and the concentration of refuse in the pitsuggests a deliberate sequestration of these remains, perhaps as afinal symbolic act of cancellation of the pit before the room’sinterment. The concentration of feasting remains in the sunken pitmay reflect the concentration of symbolic power before its burial.

The potential for understanding plant food consumption andproduction in aceramic contexts is greatly enhanced through ananalysis of residues on gourd and squash artifacts. This kind of

research should apply to other areas and time periods in whichgourds and squash rinds are preserved. Gourd and squash artifactscontaining starch residues provide direct evidence of the produc-tion and consumption of cultivated or managed plants used for foodor drink. In addition to manioc, potato, and chili pepper, this studydocuments the earliest evidence of both algarrobo and arrowroot inPeru. Also, the unique architectural feature from which the artifactswere recovered suggests a special ritual use of food in a feastingcontext. The social and ritual use of food in emergent complexsociety is not well understood, especially in Peru, and this researchenhances our potential for understanding these issues.

MethodsComparative Squash and Gourd Starch. In studying comparative gourd andsquash specimens, we found abundant starch in the dried mesocarp tissuebut relatively fewer starch granules in the exocarp. In the archaeologicalsamples, only the outer exocarp layers survive. This may explain the rela-tively few Cucurbitaceae starch granules in the residues. To differentiategourd and squash starch grains from those of other producers, we studiedmodern dried gourds collected in Chiclayo, Peru, and domestically pur-chased or grown squashes (Fig. S2 and Fig. S3). Although there is someoverlap in starch morphotypes in Cucurbitaceae, squashes and gourds canbe distinguished to genus and species based on the diagnostic morphologyof starch grains (38). Starch grains of Cucurbitaceae are also discernablefrom nonrelated taxa.

Starch Grain Sampling of Squash and Gourd Artifacts. We adapted proceduresfor extracting microfossil residues from stone tools and ceramics (see SI Materialsand Methods), producing two sediment extractions from each tool, Sediments 1and 2. To obtain Sediment 1, each artifact was submerged in distilled waterwithin a high-quality, resealable plastic bag, then placed in a sonicating waterbath to release loose residue. To obtain Sediment 2, the interior surface of eachartifact was gently brushed to further dislodge loose residue. The sedimentsobtained were then chemically dispersed using a disodium salt solution, thenlightly oxidized with hydrogen peroxide. Finally, the starch was floated out fromsediment using a heavy liquid solution of cesium chloride. Slides were mountedusing distilled water and glycerol and scanned on a Zeiss standard transmittedlight microscope equipped with polarizing light filters at 25� and 40�.

ACKNOWLEDGMENTS. Excavation in the Fox Temple in 2005 was carried outby students in the University of Missouri Field School at Buena Vista and theUniversity of Frederico Villareal of Lima. We thank the Peruvian NationalInstitute of Culture for providing the permits to excavate and export archaeo-

Fig. 3. Archaeological starch granules recovered from gourd and squash artifacts from Buena Vista. (A) Gourd (Lagenaria siceraria) starch hemisphere fromArtifact 3. (B) Manioc (Manihot esculenta) from Artifact 7. Note the central stellate fissure. (C) Potato (Solanum sp.) from Artifact 4. (D) Chili pepper (Capsicumsp.) from Artifact 6. Note the central linear feature. (E) Arrowroot (Maranta arundinacea) from Artifact 6. (F) Algarrobo (Prosopis sp.) from Artifact 3.

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botanical samples to the United States. We are grateful to Dolores Piperno,who provided insightful comments and suggestions regarding comparative

cucurbit materials. We also thank Jason Fenton and Eliana Duncan, whoprovided helpful criticisms on the manuscript.

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