The Central American isthmus was a major dispersal route for plant taxa originally brought under ... more The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals and the associated transition to food production in various regions. One of these methodologies, starch grain analysis, recovers identifiable microfossils of economic plants directly off the stone tools used to process them. We report on new starch grain evidence from Panama demonstrating the early spread of three important New World cultigens: maize (Zea mays), manioc (Manihot esculenta), and arrowroot (Maranta arundinacea). Maize starch recovered from stone tools at a site located in the Pacific lowlands of central Panama confirms previous archaeobotanical evidence for the use of maize there by 7800 -7000 cal BP. Starch evidence from preceramic sites in the less seasonal, humid premontane forests of Chiriquí province, western Panama, shows that maize and root crops were present by 7400 -5600 cal BP, several millennia earlier than previously documented. Several local starchy resources, including Zamia and Dioscorea spp., were also used. The data from both regions suggest that crop dispersals took place via diffusion or exchange of plant germplasm rather than movement of human populations practicing agriculture.
Other uses, including reproduction and distribution, or selling or licensing copies, or posting t... more Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited.
Pre-Columbian inhabitants of the western Llanos de Moxos, Bolivia, transformed large expanses of ... more Pre-Columbian inhabitants of the western Llanos de Moxos, Bolivia, transformed large expanses of seasonally flooded savannah into a complex agricultural landscape. Extensive raised field systems, along with associated canals and causeways, suggest a sophisticated approach to managing land and water resources for permanent, intensive, agricultural production. However, the detailed construction history, specific crops, and palaeoenvironmental impacts of these fields are poorly known. To investigate these issues, we analyzed stratigraphy and phytoliths from two raised fields (camellones) at the site of Campo España, western Beni, Bolivia. Results indicate that prior to field construction, vegetation was mainly palm savannah. A decline in arboreal phytolith frequencies is associated with human clearing and initial field construction. A peak in burnt grass phytoliths followed by an increase of Asteraceae, suggests a period of regular field maintenance and intensive agricultural use. Maize (Zea mays) and possibly manioc (Manihot esculenta) were grown. A small increase in arboreal phytoliths suggests some forest recovery after field abandonment. This study demonstrates the utility of phytolith and stratigraphic analyses in reconstructing construction, cultivation, and palaeoenvironmental histories of raised field systems, and assessing their role within the advanced agricultural landscape management practiced by pre-Columbian populations in the Bolivian Amazon.
Este artigo apresenta os resultados das analises de grãos de amido e de fitólito de 14 fragmentos... more Este artigo apresenta os resultados das analises de grãos de amido e de fitólito de 14 fragmentos cerâmicos recuperados em duas estruturas de cocção domésticas de uma casa semissubterânea dos proto-Jê Meridionais no sítio Bonin (Urubici, Santa Catarina) que datam entre os anos 1280 e 1420 cal. AD e 1280 e 1400 cal. AD. A inédita aplicação de técnicas para estudos de microvestígios botânicos nesta região revelou, pela primeira vez, o consumo da mandioca (Manihot esculenta), feijão (Phaseolus sp.), e, possivelmente, cará (cf. Dioscorea sp.) além de milho (Zea mays) e abóbora (Cucurbita sp.). Estes resultados mostram que os proto-Jê meridionais tiveram uma economia de subsistência baseada em uma ampla gama de alimentos de origem vegetal e praticavam a produção de alimentos mais de um século antes da conquista européia. Ao contrário dos modelos tradicionais sobre a mobilidade proto-Jê meridional, nossos dados sugerem que a produção de alimentos pode ter permitido que estas populações permanecessem o ano inteiro no planalto sul brasileiro, sem a necessidade de realizar movimentos sazonais para a encosta e para o litoral afim de adquirir a maior parte dos recursos alimentares. Nossos dados complementam evidências arqueológicas que apontam para o sedentarismo e a emergênica da complexidade social entre grupos proto-Jê do sul, incluindo a construção de grandes e bem planejadas aldeias de casas semissubterrâneas, e a criação de uma paisagem altamente estruturada no entorno de estruturas funerárias.
Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societ... more Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societies in the Late Holocene (ca. 500 to 1400 AD). In order to gain insight into the subsistence of these people, we undertook macrobotanical and phytolith analyses of sediment samples, and starch grain and phytolith analyses of artifact residues, from four large habitation sites within this region. Macrobotanical remains show the presence of maize (Zea mays), squash (Cucurbita sp.), peanut (Arachis hypogaea), cotton (Gossypium sp.), and palm fruits (Arecaceae). Microbotanical results confirm the widespread use of maize at all sites, along with manioc (Manihot esculenta), squash, and yam (Dioscorea sp.). These integrated results present the first comprehensive archaeobotanical evidence of the diversity of plants cultivated, processed, and consumed, by the pre-Hispanic inhabitants of the Amazonian lowlands of Bolivia.
Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societ... more Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societies in the Late Holocene (ca. 500 to 1400 AD). In order to gain insight into the subsistence of these people, we undertook macrobotanical and phytolith analyses of sediment samples, and starch grain and phytolith analyses of artifact residues, from four large habitation sites within this region. Macrobotanical remains show the presence of maize (Zea mays), squash (Cucurbita sp.), peanut (Arachis hypogaea), cotton (Gossypium sp.), and palm fruits (Arecaceae). Microbotanical results confirm the widespread use of maize at all sites, along with manioc (Manihot esculenta), squash, and yam (Dioscorea sp.). These integrated results present the first comprehensive archaeobotanical evidence of the diversity of plants cultivated, processed, and consumed, by the pre-Hispanic inhabitants of the Amazonian lowlands of Bolivia.
Molecular evidence indicates that the wild ancestor of maize is presently native to the seasonall... more Molecular evidence indicates that the wild ancestor of maize is presently native to the seasonally dry tropical forest of the Central Balsas watershed in southwestern Mexico. We report here on archaeological investigations in a region of the Central Balsas located near the Iguala Valley in Guerrero state that show for the first time a long sequence of human occupation and plant exploitation reaching back to the early Holocene. One of the sites excavated, the Xihuatoxtla Shelter, contains well-stratified deposits and a stone tool assemblage of bifacially flaked points, simple flake tools, and numerous handstones and milling stone bases radiocarbon dated to at least 8700 calendrical years B.P. As reported in a companion paper (Piperno DR, et al., in this issue of PNAS), starch grain and phytolith residues from the ground and chipped stone tools, plus phytoliths from directly associated sediments, provide evidence for maize (Zea mays L.) and domesticated squash (Cucurbita spp.) in contexts contemporaneous with and stratigraphically below the 8700 calendrical years B.P. date. The radiocarbon determinations, stratigraphic integrity of Xihuatoxtla's deposits, and characteristics of the stone tool assemblages associated with the maize and squash remains all indicate that these plants were early Holocene domesticates. Early agriculture in this region of Mexico appears to have involved small groups of cultivators who were shifting their settlements seasonally and engaging in a variety of subsistence pursuits.
Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in la... more Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla shelter, located in the Central Balsas Valley, that indicate that maize was present by 8,700 calendrical years ago (cal. B.P.). Phytolith data also indicate an early preceramic presence of a domesticated species of squash, possibly Cucurbita argyrosperma. The starch and phytolith data also allow an evaluation of current hypotheses about how early maize was used, and provide evidence as to the tempo and timing of human selection pressure on 2 major domestication genes in Zea and Cucurbita. Our data confirm an early Holocene chronology for maize domestication that has been previously indicated by archaeological and paleoecological phytolith, starch grain, and pollen data from south of Mexico, and reshift the focus back to an origin in the seasonal tropical forest rather than in the semiarid highlands.
Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well... more Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well as many other scholarly disciplines. These investigations are world-wide in scope and require significant amounts of paleobotanical data attesting to the exploitation of wild progenitors of crop plants and subsequent domestication and spread. Accordingly, for the past few decades the development of methods for identifying the remains of wild and domesticated plant species has been a focus of paleoethnobotany. Phytolith analysis has increasingly taken its place as an important independent contributor of data in all areas of the globe, and the volume of literature on the subject is now both very substantial and disseminated in a range of international journals. In this paper, experts who have carried out the hands-on work review the utility and importance of phytolith analysis in documenting the domestication and dispersals of crop plants around the world. It will serve as an important resource both to paleoethnobotanists and other scholars interested in the development and spread of agriculture.
Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well... more Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well as many other scholarly disciplines. These investigations are world-wide in scope and require significant amounts of paleobotanical data attesting to the exploitation of wild progenitors of crop plants and subsequent domestication and spread. Accordingly, for the past few decades the development of methods for identifying the remains of wild and domesticated plant species has been a focus of paleoethnobotany. Phytolith analysis has increasingly taken its place as an important independent contributor of data in all areas of the globe, and the volume of literature on the subject is now both very substantial and disseminated in a range of international journals. In this paper, experts who have carried out the hands-on work review the utility and importance of phytolith analysis in documenting the domestication and dispersals of crop plants around the world. It will serve as an important resource both to paleoethnobotanists and other scholars interested in the development and spread of agriculture.
Chili peppers (Capsicum spp.) are widely cultivated food plants that arose in the Americas and ar... more Chili peppers (Capsicum spp.) are widely cultivated food plants that arose in the Americas and are now incorporated into cuisines worldwide. Here, we report a genus-specific starch morphotype that provides a means to identify chili peppers from archaeological contexts and trace both their domestication and dispersal. These starch microfossils have been found at seven sites dating from 6000 years before present to European contact and ranging from the Bahamas to southern Peru. The starch grain assemblages demonstrate that maize and chilies occurred together as an ancient and widespread Neotropical plant food complex that predates pottery in some regions.
Archaeological research over the past two decades in the Middle Cauca region of central Colombia ... more Archaeological research over the past two decades in the Middle Cauca region of central Colombia has documented numerous preceramic sites dating from the terminal Pleistocene to middle Holocene, along with substantial artifactual and archaeobotanical evidence for early plant use and food production. We present a radiocarbon chronology of 26 sites, including dates previously available only in unpublished reports, and 36 new AMS dates from 11 sites. This chronology solidly establishes the preceramic (before 3600 14C BP) human occupation in the Middle Cauca. The earliest date clearly associated with cultural evidence of occupation is 10,619 ± 66 14C BP at the site of Cuba. Four sites show occupation before 10,000 14C BP, but between 10,000 and 9000 14C BP, this number increases to eleven sites. Thereafter, despite evidence of episodic volcanic activity, there is a relatively constant and continuous sequence of human occupation in the region, although small localized population movements may have occurred. The fertility of periodically renewed andisols likely attracted settlement and continued occupation of the region by people practicing early plant cultivation, based on the archaeobotanical evidence for the early adoption and use of domesticates.
We present an integrated palaeoecological and archaeobotanical study of pre-Columbian raised-fiel... more We present an integrated palaeoecological and archaeobotanical study of pre-Columbian raised-field agriculture in the Llanos de Moxos, a vast seasonally inundated forest–savanna mosaic in the Bolivian Amazon. Phytoliths from excavated raised-field soil units, together with pollen and charcoal in sediment cores from two oxbow lakes, were analysed to provide a history of land use and agriculture at the El Cerro raised-field site. The construction of raised fields involved the removal of savanna trees, and gallery forest was cleared from the area by ad 310. Despite the low fertility of Llanos de Moxos soils, we determined that pre-Columbian raised-field agriculture sufficiently improved soil conditions for maize cultivation. Fire was used as a common management practice until ad 1300, at which point, the land-use strategy shifted towards less frequent burning of savannas and raised fields. Alongside a reduction in the use of fire, sweet potato cultivation and the exploitation of Inga fruits formed part of a mixed resource strategy from ad 1300 to 1450. The pre-Columbian impact on the landscape began to lessen around ad 1450, as shown by an increase in savanna trees and gallery forest. Although agriculture at the site began to decline prior to European arrival, the abandonment of raised fields was protracted, with evidence of sweet potato cultivation occurring as late as ad 1800.
We present a multiproxy study of land use by a pre-Columbian earth mounds culture in the Bolivian... more We present a multiproxy study of land use by a pre-Columbian earth mounds culture in the Bolivian Amazon. The Monumental Mounds Region (MMR) is an archaeological sub-region characterized by hundreds of pre-Columbian habitation mounds associated with a complex network of canals and causeways, and situated in the forest–savanna mosaic of the Llanos de Moxos. Pollen, phytolith, and charcoal analyses were performed on a sediment core from a large lake (14 km2), Laguna San José (14°56.97′S, 64°29.70′W). We found evidence of high levels of anthropogenic burning from AD 400 to AD 1280, corroborating dated occupation layers in two nearby excavated habitation mounds. The charcoal decline pre-dates the arrival of Europeans by at least 100 yr, and challenges the notion that the mounds culture declined because of European colonization. We show that the surrounding savanna soils were sufficiently fertile to support crops, and the presence of maize throughout the record shows that the area was continuously cultivated despite land-use change at the end of the earth mounds culture. We suggest that burning was largely confined to the savannas, rather than forests, and that pre-Columbian deforestation was localized to the vicinity of individual habitation mounds, whereas the inter-mound areas remained largely forested.
The interpretation of Neotropical fossil phytolith assemblages for palaeoenvironmental and archae... more The interpretation of Neotropical fossil phytolith assemblages for palaeoenvironmental and archaeological reconstructions relies on the development of appropriate modern analogues. We analyzed modern phytolith assemblages from the soils of ten distinctive tropical vegetation communities in eastern lowland Bolivia, ranging from terra firme humid evergreen forest to seasonally-inundated savannah. Results show that broad ecosystems – evergreen tropical forest, semi-deciduous dry tropical forest, and savannah – can be clearly differentiated by examination of their phytolith spectra and the application of Principal Component Analysis (PCA). Differences in phytolith assemblages between particular vegetation communities within each of these ecosystems are more subtle, but can still be identified. Comparison of phytolith assemblages with pollen rain data and stable carbon isotope analyses from the same vegetation plots show that these proxies are not only complementary, but significantly improve taxonomic and ecosystem resolution, and therefore our ability to interpret palaeoenvironmental and archaeological records. Our data underline the utility of phytolith analyses for reconstructing Amazon Holocene vegetation histories and pre-Columbian land use, particularly the high spatial resolution possible with terrestrial soil-based phytolith studies.
During new excavations at the preceramic rockshelter of Casita de Piedra in western Panama, a cac... more During new excavations at the preceramic rockshelter of Casita de Piedra in western Panama, a cache of twelve unusual stones was recovered near the back wall, dating to between 4800 and 4000 cal BP. The stones include quartz, pyrite, a chalcedony vein nodule, a bladed quartz and jarosite aggregate, and a human-modified dacite cylinder. Based on the unusual lithic types and the context of the cache, we suggest that these stones once belonged to a ritual specialist, such as a healer or shaman. Special stones are frequently mentioned as being an important component of a shaman’s ritual paraphernalia in ethnographic records of various historic Native American groups throughout Central and South America, including the Bribri and Cabécar of southeastern Costa Rica and western Panama (formerly known as the “Talamanca”). The cache of stones recovered at Casita de Piedra may represent the earliest material evidence in Central America of shamanistic practice.
Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societ... more Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societies in the Late Holocene (ca. 500 to 1400 AD). In order to gain insight into the subsistence of these people, we undertook macrobotanical and phytolith analyses of sediment samples, and starch grain and phytolith analyses of artifact residues, from four large habitation sites within this region. Macrobotanical remains show the presence of maize (Zea mays), squash (Cucurbita sp.), peanut (Arachis hypogaea), cotton (Gossypium sp.), and palm fruits (Arecaceae). Microbotanical results confirm the widespread use of maize at all sites, along with manioc (Manihot esculenta), squash, and yam (Dioscorea sp.). These integrated results present the first comprehensive archaeobotanical evidence of the diversity of plants cultivated, processed, and consumed, by the pre-Hispanic inhabitants of the Amazonian lowlands of Bolivia.
The Central American isthmus was a major dispersal route for plant taxa originally brought under ... more The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals and the associated transition to food production in various regions. One of these methodologies, starch grain analysis, recovers identifiable microfossils of economic plants directly off the stone tools used to process them. We report on new starch grain evidence from Panama demonstrating the early spread of three important New World cultigens: maize (Zea mays), manioc (Manihot esculenta), and arrowroot (Maranta arundinacea). Maize starch recovered from stone tools at a site located in the Pacific lowlands of central Panama confirms previous archaeobotanical evidence for the use of maize there by 7800 -7000 cal BP. Starch evidence from preceramic sites in the less seasonal, humid premontane forests of Chiriquí province, western Panama, shows that maize and root crops were present by 7400 -5600 cal BP, several millennia earlier than previously documented. Several local starchy resources, including Zamia and Dioscorea spp., were also used. The data from both regions suggest that crop dispersals took place via diffusion or exchange of plant germplasm rather than movement of human populations practicing agriculture.
Other uses, including reproduction and distribution, or selling or licensing copies, or posting t... more Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited.
Pre-Columbian inhabitants of the western Llanos de Moxos, Bolivia, transformed large expanses of ... more Pre-Columbian inhabitants of the western Llanos de Moxos, Bolivia, transformed large expanses of seasonally flooded savannah into a complex agricultural landscape. Extensive raised field systems, along with associated canals and causeways, suggest a sophisticated approach to managing land and water resources for permanent, intensive, agricultural production. However, the detailed construction history, specific crops, and palaeoenvironmental impacts of these fields are poorly known. To investigate these issues, we analyzed stratigraphy and phytoliths from two raised fields (camellones) at the site of Campo España, western Beni, Bolivia. Results indicate that prior to field construction, vegetation was mainly palm savannah. A decline in arboreal phytolith frequencies is associated with human clearing and initial field construction. A peak in burnt grass phytoliths followed by an increase of Asteraceae, suggests a period of regular field maintenance and intensive agricultural use. Maize (Zea mays) and possibly manioc (Manihot esculenta) were grown. A small increase in arboreal phytoliths suggests some forest recovery after field abandonment. This study demonstrates the utility of phytolith and stratigraphic analyses in reconstructing construction, cultivation, and palaeoenvironmental histories of raised field systems, and assessing their role within the advanced agricultural landscape management practiced by pre-Columbian populations in the Bolivian Amazon.
Este artigo apresenta os resultados das analises de grãos de amido e de fitólito de 14 fragmentos... more Este artigo apresenta os resultados das analises de grãos de amido e de fitólito de 14 fragmentos cerâmicos recuperados em duas estruturas de cocção domésticas de uma casa semissubterânea dos proto-Jê Meridionais no sítio Bonin (Urubici, Santa Catarina) que datam entre os anos 1280 e 1420 cal. AD e 1280 e 1400 cal. AD. A inédita aplicação de técnicas para estudos de microvestígios botânicos nesta região revelou, pela primeira vez, o consumo da mandioca (Manihot esculenta), feijão (Phaseolus sp.), e, possivelmente, cará (cf. Dioscorea sp.) além de milho (Zea mays) e abóbora (Cucurbita sp.). Estes resultados mostram que os proto-Jê meridionais tiveram uma economia de subsistência baseada em uma ampla gama de alimentos de origem vegetal e praticavam a produção de alimentos mais de um século antes da conquista européia. Ao contrário dos modelos tradicionais sobre a mobilidade proto-Jê meridional, nossos dados sugerem que a produção de alimentos pode ter permitido que estas populações permanecessem o ano inteiro no planalto sul brasileiro, sem a necessidade de realizar movimentos sazonais para a encosta e para o litoral afim de adquirir a maior parte dos recursos alimentares. Nossos dados complementam evidências arqueológicas que apontam para o sedentarismo e a emergênica da complexidade social entre grupos proto-Jê do sul, incluindo a construção de grandes e bem planejadas aldeias de casas semissubterrâneas, e a criação de uma paisagem altamente estruturada no entorno de estruturas funerárias.
Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societ... more Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societies in the Late Holocene (ca. 500 to 1400 AD). In order to gain insight into the subsistence of these people, we undertook macrobotanical and phytolith analyses of sediment samples, and starch grain and phytolith analyses of artifact residues, from four large habitation sites within this region. Macrobotanical remains show the presence of maize (Zea mays), squash (Cucurbita sp.), peanut (Arachis hypogaea), cotton (Gossypium sp.), and palm fruits (Arecaceae). Microbotanical results confirm the widespread use of maize at all sites, along with manioc (Manihot esculenta), squash, and yam (Dioscorea sp.). These integrated results present the first comprehensive archaeobotanical evidence of the diversity of plants cultivated, processed, and consumed, by the pre-Hispanic inhabitants of the Amazonian lowlands of Bolivia.
Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societ... more Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societies in the Late Holocene (ca. 500 to 1400 AD). In order to gain insight into the subsistence of these people, we undertook macrobotanical and phytolith analyses of sediment samples, and starch grain and phytolith analyses of artifact residues, from four large habitation sites within this region. Macrobotanical remains show the presence of maize (Zea mays), squash (Cucurbita sp.), peanut (Arachis hypogaea), cotton (Gossypium sp.), and palm fruits (Arecaceae). Microbotanical results confirm the widespread use of maize at all sites, along with manioc (Manihot esculenta), squash, and yam (Dioscorea sp.). These integrated results present the first comprehensive archaeobotanical evidence of the diversity of plants cultivated, processed, and consumed, by the pre-Hispanic inhabitants of the Amazonian lowlands of Bolivia.
Molecular evidence indicates that the wild ancestor of maize is presently native to the seasonall... more Molecular evidence indicates that the wild ancestor of maize is presently native to the seasonally dry tropical forest of the Central Balsas watershed in southwestern Mexico. We report here on archaeological investigations in a region of the Central Balsas located near the Iguala Valley in Guerrero state that show for the first time a long sequence of human occupation and plant exploitation reaching back to the early Holocene. One of the sites excavated, the Xihuatoxtla Shelter, contains well-stratified deposits and a stone tool assemblage of bifacially flaked points, simple flake tools, and numerous handstones and milling stone bases radiocarbon dated to at least 8700 calendrical years B.P. As reported in a companion paper (Piperno DR, et al., in this issue of PNAS), starch grain and phytolith residues from the ground and chipped stone tools, plus phytoliths from directly associated sediments, provide evidence for maize (Zea mays L.) and domesticated squash (Cucurbita spp.) in contexts contemporaneous with and stratigraphically below the 8700 calendrical years B.P. date. The radiocarbon determinations, stratigraphic integrity of Xihuatoxtla's deposits, and characteristics of the stone tool assemblages associated with the maize and squash remains all indicate that these plants were early Holocene domesticates. Early agriculture in this region of Mexico appears to have involved small groups of cultivators who were shifting their settlements seasonally and engaging in a variety of subsistence pursuits.
Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in la... more Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla shelter, located in the Central Balsas Valley, that indicate that maize was present by 8,700 calendrical years ago (cal. B.P.). Phytolith data also indicate an early preceramic presence of a domesticated species of squash, possibly Cucurbita argyrosperma. The starch and phytolith data also allow an evaluation of current hypotheses about how early maize was used, and provide evidence as to the tempo and timing of human selection pressure on 2 major domestication genes in Zea and Cucurbita. Our data confirm an early Holocene chronology for maize domestication that has been previously indicated by archaeological and paleoecological phytolith, starch grain, and pollen data from south of Mexico, and reshift the focus back to an origin in the seasonal tropical forest rather than in the semiarid highlands.
Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well... more Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well as many other scholarly disciplines. These investigations are world-wide in scope and require significant amounts of paleobotanical data attesting to the exploitation of wild progenitors of crop plants and subsequent domestication and spread. Accordingly, for the past few decades the development of methods for identifying the remains of wild and domesticated plant species has been a focus of paleoethnobotany. Phytolith analysis has increasingly taken its place as an important independent contributor of data in all areas of the globe, and the volume of literature on the subject is now both very substantial and disseminated in a range of international journals. In this paper, experts who have carried out the hands-on work review the utility and importance of phytolith analysis in documenting the domestication and dispersals of crop plants around the world. It will serve as an important resource both to paleoethnobotanists and other scholars interested in the development and spread of agriculture.
Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well... more Agricultural origins and dispersals are subjects of fundamental importance to archaeology as well as many other scholarly disciplines. These investigations are world-wide in scope and require significant amounts of paleobotanical data attesting to the exploitation of wild progenitors of crop plants and subsequent domestication and spread. Accordingly, for the past few decades the development of methods for identifying the remains of wild and domesticated plant species has been a focus of paleoethnobotany. Phytolith analysis has increasingly taken its place as an important independent contributor of data in all areas of the globe, and the volume of literature on the subject is now both very substantial and disseminated in a range of international journals. In this paper, experts who have carried out the hands-on work review the utility and importance of phytolith analysis in documenting the domestication and dispersals of crop plants around the world. It will serve as an important resource both to paleoethnobotanists and other scholars interested in the development and spread of agriculture.
Chili peppers (Capsicum spp.) are widely cultivated food plants that arose in the Americas and ar... more Chili peppers (Capsicum spp.) are widely cultivated food plants that arose in the Americas and are now incorporated into cuisines worldwide. Here, we report a genus-specific starch morphotype that provides a means to identify chili peppers from archaeological contexts and trace both their domestication and dispersal. These starch microfossils have been found at seven sites dating from 6000 years before present to European contact and ranging from the Bahamas to southern Peru. The starch grain assemblages demonstrate that maize and chilies occurred together as an ancient and widespread Neotropical plant food complex that predates pottery in some regions.
Archaeological research over the past two decades in the Middle Cauca region of central Colombia ... more Archaeological research over the past two decades in the Middle Cauca region of central Colombia has documented numerous preceramic sites dating from the terminal Pleistocene to middle Holocene, along with substantial artifactual and archaeobotanical evidence for early plant use and food production. We present a radiocarbon chronology of 26 sites, including dates previously available only in unpublished reports, and 36 new AMS dates from 11 sites. This chronology solidly establishes the preceramic (before 3600 14C BP) human occupation in the Middle Cauca. The earliest date clearly associated with cultural evidence of occupation is 10,619 ± 66 14C BP at the site of Cuba. Four sites show occupation before 10,000 14C BP, but between 10,000 and 9000 14C BP, this number increases to eleven sites. Thereafter, despite evidence of episodic volcanic activity, there is a relatively constant and continuous sequence of human occupation in the region, although small localized population movements may have occurred. The fertility of periodically renewed andisols likely attracted settlement and continued occupation of the region by people practicing early plant cultivation, based on the archaeobotanical evidence for the early adoption and use of domesticates.
We present an integrated palaeoecological and archaeobotanical study of pre-Columbian raised-fiel... more We present an integrated palaeoecological and archaeobotanical study of pre-Columbian raised-field agriculture in the Llanos de Moxos, a vast seasonally inundated forest–savanna mosaic in the Bolivian Amazon. Phytoliths from excavated raised-field soil units, together with pollen and charcoal in sediment cores from two oxbow lakes, were analysed to provide a history of land use and agriculture at the El Cerro raised-field site. The construction of raised fields involved the removal of savanna trees, and gallery forest was cleared from the area by ad 310. Despite the low fertility of Llanos de Moxos soils, we determined that pre-Columbian raised-field agriculture sufficiently improved soil conditions for maize cultivation. Fire was used as a common management practice until ad 1300, at which point, the land-use strategy shifted towards less frequent burning of savannas and raised fields. Alongside a reduction in the use of fire, sweet potato cultivation and the exploitation of Inga fruits formed part of a mixed resource strategy from ad 1300 to 1450. The pre-Columbian impact on the landscape began to lessen around ad 1450, as shown by an increase in savanna trees and gallery forest. Although agriculture at the site began to decline prior to European arrival, the abandonment of raised fields was protracted, with evidence of sweet potato cultivation occurring as late as ad 1800.
We present a multiproxy study of land use by a pre-Columbian earth mounds culture in the Bolivian... more We present a multiproxy study of land use by a pre-Columbian earth mounds culture in the Bolivian Amazon. The Monumental Mounds Region (MMR) is an archaeological sub-region characterized by hundreds of pre-Columbian habitation mounds associated with a complex network of canals and causeways, and situated in the forest–savanna mosaic of the Llanos de Moxos. Pollen, phytolith, and charcoal analyses were performed on a sediment core from a large lake (14 km2), Laguna San José (14°56.97′S, 64°29.70′W). We found evidence of high levels of anthropogenic burning from AD 400 to AD 1280, corroborating dated occupation layers in two nearby excavated habitation mounds. The charcoal decline pre-dates the arrival of Europeans by at least 100 yr, and challenges the notion that the mounds culture declined because of European colonization. We show that the surrounding savanna soils were sufficiently fertile to support crops, and the presence of maize throughout the record shows that the area was continuously cultivated despite land-use change at the end of the earth mounds culture. We suggest that burning was largely confined to the savannas, rather than forests, and that pre-Columbian deforestation was localized to the vicinity of individual habitation mounds, whereas the inter-mound areas remained largely forested.
The interpretation of Neotropical fossil phytolith assemblages for palaeoenvironmental and archae... more The interpretation of Neotropical fossil phytolith assemblages for palaeoenvironmental and archaeological reconstructions relies on the development of appropriate modern analogues. We analyzed modern phytolith assemblages from the soils of ten distinctive tropical vegetation communities in eastern lowland Bolivia, ranging from terra firme humid evergreen forest to seasonally-inundated savannah. Results show that broad ecosystems – evergreen tropical forest, semi-deciduous dry tropical forest, and savannah – can be clearly differentiated by examination of their phytolith spectra and the application of Principal Component Analysis (PCA). Differences in phytolith assemblages between particular vegetation communities within each of these ecosystems are more subtle, but can still be identified. Comparison of phytolith assemblages with pollen rain data and stable carbon isotope analyses from the same vegetation plots show that these proxies are not only complementary, but significantly improve taxonomic and ecosystem resolution, and therefore our ability to interpret palaeoenvironmental and archaeological records. Our data underline the utility of phytolith analyses for reconstructing Amazon Holocene vegetation histories and pre-Columbian land use, particularly the high spatial resolution possible with terrestrial soil-based phytolith studies.
During new excavations at the preceramic rockshelter of Casita de Piedra in western Panama, a cac... more During new excavations at the preceramic rockshelter of Casita de Piedra in western Panama, a cache of twelve unusual stones was recovered near the back wall, dating to between 4800 and 4000 cal BP. The stones include quartz, pyrite, a chalcedony vein nodule, a bladed quartz and jarosite aggregate, and a human-modified dacite cylinder. Based on the unusual lithic types and the context of the cache, we suggest that these stones once belonged to a ritual specialist, such as a healer or shaman. Special stones are frequently mentioned as being an important component of a shaman’s ritual paraphernalia in ethnographic records of various historic Native American groups throughout Central and South America, including the Bribri and Cabécar of southeastern Costa Rica and western Panama (formerly known as the “Talamanca”). The cache of stones recovered at Casita de Piedra may represent the earliest material evidence in Central America of shamanistic practice.
Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societ... more Although sparsely populated today, the Llanos de Mojos, Bolivia, sustained large sedentary societies in the Late Holocene (ca. 500 to 1400 AD). In order to gain insight into the subsistence of these people, we undertook macrobotanical and phytolith analyses of sediment samples, and starch grain and phytolith analyses of artifact residues, from four large habitation sites within this region. Macrobotanical remains show the presence of maize (Zea mays), squash (Cucurbita sp.), peanut (Arachis hypogaea), cotton (Gossypium sp.), and palm fruits (Arecaceae). Microbotanical results confirm the widespread use of maize at all sites, along with manioc (Manihot esculenta), squash, and yam (Dioscorea sp.). These integrated results present the first comprehensive archaeobotanical evidence of the diversity of plants cultivated, processed, and consumed, by the pre-Hispanic inhabitants of the Amazonian lowlands of Bolivia.
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