Palynology provides a record of past environmental change in the Maya Lowlands. The underlying principles are simple, but, as with all proxies, there are limitations. During the late glacial period, environmental change was governed by climate, which was cooler and much drier and supported sparse temperate vegetation. The early Holocene epoch was warmer and very wet in the southern Lowlands when mesic tropical forests predominated, while the northern Yucatan Peninsula was edaphically dry until eustatic sea level rose. The modern distributions of plant associations and climatic gradients were established at the end of the early Holocene. Climatic variability continued throughout the Holocene. However, the ability of palynology to identify climatic events is hindered after the Maya became numerous in the Lowlands. Then, multidisciplinary studies provide a better interpretation of events, especially during the late Holocene. Pollen records poorly reflect cyclical droughts seen in isotopic records, as natural vegetation has adapted to these fluctuations.

Since the late 1950s, scientists have used sediment cores from lakes on the Yucatan Peninsula to explore the complex interactions among climate, environment, and ancient Maya culture. Early paleolimnological studies generally assumed that late Holocene climate was invariable. Consequently, paleolimnologically inferred environmental changes that occurred during the past 3,000 years or so—for example, forest decline and soil erosion—were attributed wholly to anthropogenic activities such as land clearance for agriculture and construction. Recent high-resolution, proxy-based paleoclimate records from continental and insular sites around the Caribbean Sea contradict the assumption of late Holocene climate stability. Instead, these core data suggest that regional drying began about 3,000 years ago and that the past three millennia were characterized by variable moisture availability. Paleoclimate inferences from Lakes Chichancanab and Punta Laguna, northern Yucatan Peninsula, indicate that drought events over the past 2,600 years were cyclical. These dry events, thought to have been driven by solar forcing, appear to have occurred approximately every two centuries (about 208 years). The driest period of the late Holocene occurred between A.D. 800 and 1000, coincident with the Classic Maya Collapse. We review the history of paleolimnological studies in the Maya Lowlands, discuss the difficulty of differentiating climatic signals from anthropogenic signals in late Holocene lake sediment profiles, and assess current understanding of past climate changes in the region based on regional lacustrine sediment studies.

Continuing analysis of the site of Chichen Itza suggests that its construction dates primarily to the Late Classic period, ca. a.d. 700–1000, rather than the Early Postclassic. This paper examines the implications of this redating for the well-known “Toltec” problem. Since Chichen largely antedated Tollan-phase Tula, we conclude that what is usually identified as Toltec imagery in fact dates to an earlier Epiclassic horizon extending from Morelos and Puebla to the Gulf Coast and Yucatan. Chichen Itza, we suggest, was the eastern node in a network of shrine centers dedicated primarily to Quetzalcoatl/Kukulcan. This network transcended political boundaries and included such sites as Cholula, Cacaxtla, El TajIn, Xochicalco, and ultimately Tula. The Quetzalcoatl cult is manifested by a specific complex of traits and seems to have expanded militarily with messianic vigor. Pilgrimage was also an important activity at these centers. This cult axis apparently continued into the Postclassic period, and was responsible for the distribution of the Mixteca-Puebla art style. In Yucatan, Mayapan would seem to have assumed Chichen's position as the major Yucatecan node, although accompanied by several new shrines along the Caribbean coast.

The Classic-period households of the Ceren village in the southeastern periphery of the Maya area provisioned themselves by one of three different economies. (1) Household members produced many items for intrahousehold use, including architecture, food, and some artifacts, with no input from outside. (2) Each household produced some commodity in excess of what they needed for their internal consumption, by means of part-time specialization, and they used this for exchange with other households within the village or nearby. This is termed the horizontal or village economy. The commodities included craft items such as groundstone tools and painted gourds as well as agricultural specialities such as agave for fiber. (3) Each household obtained distant exotic items, such as obsidian tools, jade axes, and polychrome serving ceramics, by exchanging their household surplus commodities in elite centers. In this paper, this is called the vertical economy. The choices available to commoner households in negotiating economic transactions in various elite centers gave them economic power and could have the effect of constraining the elite in setting exchange equivalencies. This is quite different from the view from the top of the pyramid which generally depicts commoners as the exploited class at the bottom of a powerful political and economic hierarchy.

Archaeological and ecological investigations in the Mirador Basin of northern Guatemala have recovered archaeological, phytolith, palynological, and pedological data relevant to the early occupation and development of Maya civilization in a specific environmental matrix. Fluctuation in vegetation types as evident in cores and archaeological profiles suggest that the seasonally wet, forested bajo environment currently found in the northern Peten was anciently more of a perennially wet marsh system that may have been heavily used and influenced by large Preclassic occupations. Data suggest that climatic and environmental factors correspond with the cultural process in the Mirador Basin, and research in progress is oriented to further elucidating these issues.

To investigate geographic origins of the sacrificial Burials 2–5 from the Moon Pyramid at Teotihuacan and to reconstruct changes in residence since their childhoods, we analyzed tooth enamel for oxygen- and strontium-isotope ratios and bone just for oxygen-isotope ratios. The combination of these analytical techniques involves both climatic and geological variables, therefore enhancing resolution of geographic identification. Most of the sacrificed individuals appear to have been born in a foreign location. These regions probably include other areas within the Basin of Mexico and the central highlands, as well as the Gulf Coast and the Sierra Madre del Sur. Other possible regions of origin are the southern highlands, the Motagua Valley, and the Maya Lowlands. There is considerable overlap in the oxygen-isotope ratios between the Moon Pyramid and Feathered Serpent Pyramid victims, but each structure contains a group of isotopically distinct individuals. The Moon Pyramid sacrifices include some individuals with high oxygen-isotope ratios, possibly indicating the Gulf Coast or Maya Lowlands, whereas the Feathered Serpent Pyramid contains a distinct group with very low oxygen-isotope ratios, possibly indicating Oaxaca, Michoacan, or the coastal plain and piedmont of Guatemala. The sacrifices in the two pyramids also differ in their patterns of movement. Most of the Moon Pyramid victims appear to have arrived in the city recently, but the majority of those from the Feathered Serpent Pyramid had lived in Teotihuacan for a long time before their death.

Mesoamerican household sites were often deserted gradually, leaving very little de facto refuse for analysis. Starting with archaeological and paleobiological distribution patterns, this study adds a new dimension to the spatial study of two Classic households by plotting chemical concentrations in probable activity areas.

The Petexbatun region has a series of upland ridges surrounded by lowland wetlands. In Preclassic times, ancient Maya peoples began colonizing the region along waterways. Although few in number, they cleared large areas of upland tropical forest for agriculture and induced significant soil erosion. Population contracted in the region during the Early Classic, and mature tropical forest growth returned. During the Late Classic, population expanded rapidly across the region, forest clearance resumed, and desirable, intensively cultivated, upland areas were divided by an elaborate wall system. Upland agriculture during the Late Classic included the use of several types of terracing that significantly checked soil erosion during this period. Considerable variation may have existed between the urban agriculture practiced in the region's three major centers—Dos Pilas, Tamarindito, and Aguateca.

Between a.d. 760 and 930, millions of Maya disappeared from the Earth. We examine changes in the physical environment in which the Maya lived. The ice-core evidence from Greenland indicates that around the time of the Maya Collapse, a minimum in solar insolation and a low in solar activity occurred, accompanied by severe cold and dryness over Greenland, indicating hemispheric climatic conditions propitious for drought in the Maya Lowlands. In the northeastern Caribbean, sea-surface salinity (SSS) was lowered. The most severe drought of the past 7,000 years devastated the Yucatan Peninsula. Large Maya cities collapsed in four phases of abandonment spaced about fifty years apart around a.d. 760, 810, 860, and 910. A new core taken from Lake Chichancanab in Quintana Roo shows three peak episodes of brutal drought within a 150- to 200-year drought. A marine core from the Cariaco Basin off Venezuela precisely dates four severe drought episodes to 760, 810, 860, and 910, coincident with the four phases of abandonment of cities. The long-term drought appears to have lasted from 760 to 930 in the Cariaco Basin. The climatic changes were the most drastic the Maya had faced in the preceding 1,500 years and the most severe of the preceding 7,000 years.

From 1989 to 1996, excavation and surveys were carried out at dozens of sites and intersite areas in the southwestern Peten by the Defensive Systems Subproject of the Vanderbilt Petexbatun Regional Archaeological Project and by subsequent related Vanderbilt investigations. The excavations and analyses explored fortification systems, related settlement, and artifactual evidence. Beginning at about a.d. 760, the major centers of the Classic Maya civilization in the Petexbatun region were fortified by a massive expenditure of labor on defensive walls of masonry, usually surmounted by wooden palisades. As warfare accelerated, major centers and later even small hilltop villages were located in highly defensible positions and were fortified by walls, palisades, moats, and baffled gateways. Despite these efforts, all major centers were virtually abandoned by the early ninth century. By a.d. 830, only the island fortress of Punta de Chimino and a very reduced and scattered population remained in the Petexbatun region.

Archaeological investigations at Aguateca, Guatemala, by the Petexbatun Regional Archaeological Project have provided clues to the intriguing sequence of the downfall of this Maya center. The earliest substantial occupation at Aguateca dates to the Late Preclassic period. After very little presence during the Early Classic period, Aguateca rapidly grew into a densely occupied center, probably at the beginning of the eighth century a.d. Migration from other areas may have contributed to this rapid population growth. In the late eighth century, extensive defensive walls were constructed, most likely as a response to intensified warfare. Despite this defensive effort, Aguateca was finally attacked and brought down by enemies probably at the beginning of the ninth century. The center appears to have been almost completely abandoned soon after this event. This reconstructed sequence confirms other evidence of the Petexbatun Project that intensified warfare played an important role in the Classic Maya collapse.

E-group architectural assemblages, constructed and used for more than a millennium in the Maya Lowlands, are among the most distinctive and enduring forms in Mesoamerican monumental architecture. Since the 1920s, E-groups have been thought to mark the solstices and equinoxes, but more recent investigations have shown that these alignments were rarely accurate. We argue that accurate solar alignment was probably only a minor element, and primarily an early one, of a larger set of metaphorically linked design considerations that included concepts of sacred geography, ritual performance in reference to yearly solar and agricultural cycles, and longer cycles of time, especially katuns, that played a role in Lowland Maya geopolitical structuring.

Statements concerning the function of intrasite Maya causeways often focus on inferred ritual purposes or on symbolic kinship alliances rather than on the more practical roles that such roads may have served. Data collected on an extensive intrasite causeway system at Caracol, Belize, demonstrate that the primary role of its sacbes lay in facilitating the administrative control of people, goods, and services. An estimated 75 km of roads not only served intrasite communication and transport; they also affected the political and economic integration of this huge center.

Archaeological excavations carried out during the past five years along the Pacific coast of Mexico, Guatemala, and El Salvador have recovered 79 new 14C dates for the Late Archaic and Early to Middle Formative periods. We analyze these new dates along with 25 previously published dates to refine a sequence of 10 archaeological phases spanning almost three and a half millennia, from ca. 4000 to 650 B.C. The phases are summarized with a brief description of their most salient characteristics. We include illustrations of the Early Formative period ceramics and figurines from the Mazatan region. The sequence of phases reveals a trajectory of cultural evolution beginning in the Archaic period with the mobile hunting, fishing, and gathering Chantuto people. By 1550 B.C., the first ceramic-using sedentary communities appeared on the coast of Chiapas. They were hunter-fisher-gatherers who supplemented their food supply with cultivated plants, including maize and beans. We suggest that by the Locona phase (1400–1250 B.C.) in Chiapas, they began the transition from egalitarian sociopolitical organization to simple chiefdoms, leaving behind evidence of large-scale architectural constructions, long-distance imports such as obsidian and jade, and elaborately crafted prestige goods. Also in Chiapas, during the Cherla phase (1100–1000 B.C.), ceramic and figurine styles, nearly identical to those found at San Lorenzo Tenochtitlan on the Gulf Coast, made their first appearance. Many of the local artifact styles were gradually replaced by styles that became increasingly widespread in Mesoamerica. The chronology presented here shows that these changes were roughly contemporaneous with similar ones in neighboring regions of Mesoamerica.

The Classic Maya esteemed jadeite not only for its preciousness and beauty but also as stone of great symbolic import. This paper examines the religious significance of jade and certain types of jade artifacts among the Classic Maya. In this study, I note that the Classic Maya ascribed a number of meanings to jade, including maize, centrality, and rulership, as well as a material embodiment of wind and the vitalizing breath soul. Because of its close relationship to the breath spirit, jade was an important component of funerary rites and the ritual conjuring of gods and ancestors. Carved in floral form, jade earspools were considered supernatural sources or passageways for the breath spirit, frequently portrayed as a bead or a serpent emerging from the center of the jade flare. A common Classic Maya death expression, och b'ih, pertains directly to resurrection of the soul through the symbolism of earspools. Many of the symbolic meanings and imagery found with Classic Maya jade also appears with other cultures of ancient Mesoamerica, including Teotihuacan, Xochicalco, and the contact-period Aztec. Rather than being wholly of Classic Maya origin, many aspects of this jade symbolism and related artifacts can be also found among the earlier Middle Formative Olmec.

A technological typology for the description and analysis of Mesoamerican obsidian industries is proposed, and its relative merits vis-à-vis Sheets's (1975a) “behavioral” typology are briefly explored. The typology is used to classify and describe a pristine deposit of obsidian-blade refuse recovered from the Early Classic Maya site of Ojo de Agua, Chiapas, Mexico. Analysis of this deposit revealed that the obsidian artifacts were manufacturing refuse resulting from the production of fine prismatic blades from polyhedral cores imported from highland Guatemala. The obsidian refuse was recovered from a workshop dump rather than from an actual workshop.

Data are presented from archaeological excavations conducted by the Institute de Antropología e Historia (IDEAH) in the Mundo Perdido architectural complex, Tikal, Guatemala, from 1979 to 1984. After a brief summary of the data pertaining to the Middle Preclassic, Late Preclassic, and Early Classic periods, new results are presented from investigations of the Late Classic occupation of this group. Many marked social changes at Tikal are revealed through the Mundo Perdido data within a cultural context that emphasizes remarkable continuity.

Recent adjustments to the chronology of the northern Maya Lowlands have brought about a closer alignment of the decline of Terminal Classic/Early Postclassic Yucatecan polities with the collapse of the southern Maya states. The collapse of the entire Classic-period societal structure throughout the lowlands can now be compressed into a 200- or 250-year period and seen as a progressive chain of events that began in the south and culminated with the fall of Chichen Itza in the eleventh century. This new reconstruction has led us to propose eliminating the Early Postclassic period, the existence of which was based largely on a purportedly late occupation of Chichen Itza. We assign this final occupation of the Itza capital to the Terminal Classic period, which ended sometime in the eleventh century in the northern Maya Lowlands.

Obsidian artifact sourcing studies performed over the last 25 years have identified obsidian from outcrops around the communities of Zinapecuaro and Ucareo, Michoacan, at sites widely distributed in time and space. Recent data indicate that Zinapecuaro and Ucareo constitute distinct obsidian sources, although their proximity to each other and their similar chemical compositions merit their consideration as collectively comprising part of an obsidian source area. Sourcing studies that used Ucareo as well as Zinapecuaro source reference samples provide strong evidence of considerably greater pre-Hispanic utilization of the Ucareo source, and raise the possibility that at least some artifacts attributed to Zinapecuaro in studies that did not use Ucareo reference samples may be from the Ucareo source. These findings are supported by recent archaeological evidence of considerably greater exploitation of the Ucareo source, including what is probably one of the largest known pre-Hispanic quarries. Preliminary data provide a tentative chronology for settlement and exploitation of the source area.

The importance of Maya sea trade was the sea's integrating role as provider of ritual and subsistence resources and ritual symbolism in the Maya economy. Coastal as opposed to inland transportation of obsidian and other exotics was enhanced because of coastal–inland exchange within the southern Maya lowlands. Results are presented on fieldwork conducted to investigate Maya sea trade by the South Coastal Archaeology in Belize (SCAB) project in the Port Honduras area of south-coastal Belize between Punta Gorda and Punta Negra. The research focused on identifying features characteristic of Maya trading ports that participated in long-distance trade and their impact on regional economies. The first part of the project, with fieldwork in 1982, identified the offshore island site of Wild Cane Cay as a trading port from the Classic through Postclassic periods (a.d. 300–1500). The discovery of some 30 sites during the second phase of the project, dating from the Protoclassic through the Postclassic periods (a.d. 1–1500), indicated that the coastal area had a long period of settlement in contrast to the inland area of southern Belize where settlement was concentrated during the Late Classic period (a.d. 600–900). The patterns of distribution of similar-sourced obsidian, and blades instead of cores within the south-coastal area indicated that some exotics were regionally distributed and that Wild Cane Cay was the nexus of regional distribution. The importance of coastal-inland exchange is underscored by the presence of specialized salt-production sites, coastal resources, and inland goods—notably “unit-stamped” pottery and moldmade figurine whistles.