Lowland Maya civilization flourished in the tropical region of the Yucatan peninsula and environs for more than 2500 years (~1000 BCE to 1500 CE). Known for its sophistication in writing, art, architecture, astronomy, and mathematics, Maya civilization still poses questions about the nature of its cities and surrounding populations because of its location in an inaccessible forest. In 2016, an aerial lidar survey across 2144 square kilometers of northern Guatemala mapped natural terrain and archaeological features over several distinct areas. We present results from these data, revealing interconnected urban settlement and landscapes with extensive infrastructural development. Studied through a joint international effort of interdisciplinary teams sharing protocols, this lidar survey compels a reevaluation of Maya demography, agriculture, and political economy and suggests future avenues of field research.

Paleoclimate records indicate a series of severe droughts was associated with societal collapse of the Classic Maya during the Terminal Classic period (∼800-950 C.E.). Evidence for drought largely derives from the drier, less populated northern Maya Lowlands but does not explain more pronounced and earlier societal disruption in the relatively humid southern Maya Lowlands. Here we apply hydrogen and carbon isotope compositions of plant wax lipids in two lake sediment cores to assess changes in water availability and land use in both the northern and southern Maya lowlands. We show that relatively more intense drying occurred in the southern lowlands than in the northern lowlands during the Terminal Classic period, consistent with earlier and more persistent societal decline in the south. Our results also indicate a period of substantial drying in the southern Maya Lowlands from ∼200 C.E. to 500 C.E., during the Terminal Preclassic and Early Classic periods. Plant wax carbon isotope records indicate a decline in C 4 plants in both lake catchments during the Early Classic period, interpreted to reflect a shift from extensive agriculture to intensive, waterconservative maize cultivation that was motivated by a drying climate. Our results imply that agricultural adaptations developed in response to earlier droughts were initially successful, but failed under the more severe droughts of the Terminal Classic period.Maya civilization | drought | societal collapse | climate adaptation | compound-specific isotope analysis

Paleoclimatologists have discovered abundant evidence that droughts coincided with collapse of the Lowland Classic Maya civilization, and some argue that climate change contributed to societal disintegration. Many archaeologists, however, maintain that drought cannot explain the timing or complex nature of societal changes at the end of the Classic Period, between the eighth and eleventh centuries CE. This review presents a compilation of climate proxy data indicating that droughts in the ninth to eleventh century were the most severe and frequent in Maya prehistory. Comparison with recent archaeological evidence, however, indicates an earlier beginning for complex economic and political processes that led to the disintegration of states in the southern region of the Maya lowlands that precedes major droughts. Nonetheless, drought clearly contributed to the unusual severity of the Classic Maya collapse, and helped to inhibit the type of recovery seen in earlier periods of Maya prehistory. In the drier northern Maya Lowlands, a later political collapse at ca. 1000 CE appears to be related to ongoing extreme drought. Future interdisciplinary research should use more refined climatological and archaeological data to examine the relationship between climate and social processes throughout the entirety of Maya prehistory. 613

Excavations beneath the Copan Acropolis provide the most complete record known for the origins and development of an Early Classic Maya royal complex (ca. a.d. 420–650). Beginning at the time of the historically identified dynastic founder, the earliest levels include the first royal compound, centered on a small talud-tablero platform, a vaulted tomb that may be that of the founder, and an adjacent tomb that may be that of the founder's wife and dynastic matriarch. The timing and development of architecture provide evidence of the founding and growth of Copan as the capital of a Classic-period polity during the reigns of the first seven kings (a.d. 426–544). By the reigns of Rulers 8–11 (a.d. 544–628), the Early Classic Acropolis covered about the same area as its final version in the Late Classic. Documentation of specific Acropolis buildings provides evidence of the external connections that reinforced the authority of Copan's Early Classic kings. Building sequences reflect the perpetuation of political power by using important locations as symbolic links to the sacred past. The Early Classic Acropolis also provides new evidence for the beginnings of palace architecture that have important implications for the origins of Maya state-level organizations. Overall, the findings from the Early Classic Copan Acropolis promise to significantly advance our understanding of the origins and development of Maya state systems.

Investigations of Classic period (a.d. 400–900) settlement in the El Paraíso Valley, western Honduras, have identified a pattern of paired centers that suggests a previously unrecognized model of political organization in the Maya area. In the El Paraíso Valley, the largely contemporary, equally-sized, and proximate centers of El Cafetal and El Paraíso differ radically from one another in their spatial organization, construction techniques, architectural embellishment, use of open space, and portable material culture. Analysis of these differences suggests that El Cafetal was inhabited by an autochthonous population while El Paraíso was founded under the auspices of the Copan dynasty as an administrative outpost. We suggest that the juxtaposition of these two sites results from a regional strategy of sociopolitical integration implemented by Copan rulers that was adapted to the ethnically diverse regions along the edge of the Copan kingdom.