Supporting Information Petraglia et al. 10.1073/pnas.0810842106 SI Text Although the available hard evidence for vegetation in the Paleovegetation Reconstruction. Microlithic technologies occur region is limited, the correlation between available pollen data- during the transition from the terminal phase of Oxygen Isotope sets and global climatic proxies provides a basis for reconstruct- Stage (OIS) 3 as climatic conditions moved toward the full glacial ing vegetation patterns in contrast to modern (Holocene) inter- of OIS 2. This climatic shift is tied to the downturn from the peak glacial and Last Glacial Maximum conditions. The general on Northern Hemisphere summer insolation (Fig. S1). This shift contrasts between these periods have been reconstructed by is expected to see a strong reduction on summer (southwest) Adams and Faure (14) on the basis of a pan-Asian dataset. Our monsoon rainfall (1, 2). The decrease in summer monsoons and reconstruction approximates a halfway point between these 2 drying is reflected in several regional datasets, including high extremes. However, rather than using the broad and inaccurate dust-particle spikes and d18O drops in the Dunde Ice Cap modern vegetation baseline of Adams and Faure (14), we have (Qinghai, China) and Guliya Ice Cap (Tibet) (3, 4). But this started from the more detailed South Asian vegetation maps of period is also characterized by abrupt oscillations in temperature Puri et al. (15) and Asouti and Fuller (11), taking into account on a Ϸ200 year cycle (4). Vegetation zones would have been correlations with topography, underlying geology and individual reshuffled during this period, and it is likely that semiarid South Asian tree species ecologies (Fig. S2). These correlations tropical zones had nonanalogue ecosystems, as is postulated for were assessed by comparing maps by eye, but nevertheless permit Europe during this period (5, 6). Nevertheless, comparisons with a more precise model of potential vegetation zones than the basic interglacial conditions and glacial maxima conditions recorded maps of Adams and Faure (14). The resulting vegetation model in a few long pollen sequences from the Arabian sea near South (Fig. 2) presents a plausible hypothesis to account for the India (7) and southern Arabia (8) provide guidance on recon- available paleoclimatic and paleobotanical evidence. The basis structing the vegetation. Under glacial maxima conditions (ca. for the 5 vegetation zones in our reconstruction are as follows: 20 and 60 ka), drier conditions are marked by high values of the Zone 1. This zone represented an extended Thar Desert zone of salt-tolerant desertic indicators Chenopodiaceae/Amaran- desertic and desert-margin vegetation, which is expected to thaceae, although these may also result from depressed sea levels support little or no forager population and therefore, together and the expansion of saline marshes with lower sea levels and a with extensive desertic areas reconstructed for the Iranian shift in inputs biased toward the northeast winter monsoon, plateau and Arabia, to create a disjunction between human bringing greater input from the Thar Desert. Despite this aridity, populations in India and those in westernmost Asia. We expect it is clear from the presence of evergreen tropical taxa that wet the contours of this zone to follow the general pattern of modern evergreen forests persisted, probably in refugia in Sri Lanka and rainfall contours but to take in more of them, reflecting reduced the southwestern parts of the Indian peninsula, comparable with precipitation over the entire region, with the exception of the the rain forest refugia of Sundanland shelf of Southeast Asia (see area around Mt. Abu, Rajasthan, which, due to its high elevation, ref. 9). The presence of refugia in southern South Asia are is expected to have higher amounts of rainfall than its surround- implied by the presence of endemic tropical evergreen taxa ing lowlands and to remain, as it is today, an island of lusher disjunct from sister taxa in Assam and mainland Southeast Asia vegetation. In addition, we reconstruct an expected desert in the (10, 11) as well as by evidence from the continuous presence of Southern Deccan (Malnad zone) focused around modern Bel- the tropical evergreen Artocarpus seeds through the sequence at lary, as this area has the driest bioclimate in India outside the Beli-lena Kitulgala cave in Sri Lanka (12). During these periods Thar Desert (16) and is only marginally nondesertic. With grass pollen levels are low, suggesting a more-restricted distri- slightly less rainfall, it can be expected to be desertic. The bution of savannah grasslands than under recent conditions. Low Jwalapuram sites, therefore, represent the occupation of lusher values of Melastomataceae/Combretaceae (which include a savannah just east of the Bellary District. broad range of evergreen as well as dry deciduous taxa) and Zone 2. This zone represents a combined zone of savannah–scrub Moraceae/Urticaceae attests to the persistence of tropical rain (dry evergreen) vegetation (Acacia spp., Albizia, Capparis, some forest patches and deciduous woodland, presumably in a mosaic Anogeissus) and the drier elements of modern dry deciduous with some grassland and some semidesert vegetation. By con- woodlands (Anogeissus and Terminalia spp.). We reconstruct this trast, interglacials, such as the early Holocene, have much higher as a savannah–woodland mosaic. tree levels as well as wetland taxa (Cyperaceae) and coastal Zone 3. This area represents zones of the core dry deciduous and mangroves (Rhiphoraceae). wetter dry deciduous taxa, notably teak (Tactona grandis), more During the period of interest here—from ca. 35 to 25 ka—we Terminalia spp., and Hardwickia in some areas of Basaltic soil. can reconstruct a semiglacial-era mosaic. Most taxa show trends The boundaries of this and the previous zone follow contours similar to those of the glacial periods, e.g., declining grasses and closer to those between wetter and drier grades of dry deciduous evergreen forest taxa such as Piperaceae. However, there was woodlands today. some increase of total tree pollen, presumably mostly from Zone 4. This zone is the dry-to-moist deciduous woodland zone, tropical dry (deciduous) taxa, as well as a slight rise in the similar to the one above but having a higher dominance of evidence for freshwater wetland (Cyperaceae). Interestingly, Dipterocarpacaeae (Hopea, Shorea, Dipterocarpus) and less Tec- there is a complete absence of mangrove pollen. Taken together, tona, keeping with its more easterly distribution and modern these factors imply that interior regions had a developed mosaic west-to-east variation. of woodland, with patchy grassland and wetlands. The absence Zone 5. The Ganges plains and East Indian lowlands are expected of mangrove may hint at less attractive coastal environments to have been a mosaic of grassland, marshland, and river courses than existed earlier or under Holocene conditions. Also of with deciduous Dipetercarop forest made up of taxa of zone 4 interest is microcharcoal from the Sandynallah swamp, Palni above. This makeup is in keeping with the woodland elements of Hills (13), which implies that human groups practiced some these regions today in relation to adjacent upland forests. vegetation burning for maintaining the vegetation mosaic or Zone 6. This is the restricted zone of true moist deciduous forests, driving game. shifted west toward the higher rainfall of the northwest coast, but Petraglia et al. www.pnas.org/cgi/content/short/0810842106 1of13 which is presumed to be lower than today and is inadequate for Core Types. Core types include single platform core, bifacially true evergreen rainforests. A parallel zone to the more seasonal flaked slabs, unifacially flaked cobbles/slabs, bidirectional core, rainfall areas of east and northwest Sri Lanka can be expected. multiplatform core, blade core, microblade core, pressure blade Zone 7. The Western Ghats evergreen rain forests are recon- core, pressure microblade core, bifacial core, core fragment, structed as a more limited refugial forest on the southwest, which bipolar core, discoidal core, Levallois core, pseudoLevallois would always have been highest in rainfall. A parallel zone is core, Levallois point core, recurrent Levallois core, and handaxe. reconstructed from southwest Sri Lanka. Zone 8. This zone represents higher elevation and rain forests with Retouched Flake Types. Retouched flake types include asymmetric more temperate elements, including taxonomic disjunctures backed, symmetric backed, broken backed, double backed (i.e., from the Himalayas. This includes the distinctive shoal elements both lateral margins), burin, retouched burin spall, double side of the Nilgiri hills today. The highest elevations of the hills may retouched, double end and side retouched, double side and end have been grasslands above the treeline. General parallels can be retouched, double side and double end retouched, retouched expected in the highest elevations of Sri Lanka. redirecting, end retouched, carinated end, double end, notched, The conditions in peninsular India should, however, be seen notched side/side and end/end/double side/double end/double together with the vegetation over a wider region. The drier and side and end, or double side and double end, ‘‘slug,’’ retouched cooler conditions would be expected to have made semideserting flaked piece, and retouched tabular piece. areas desert, and deserts grew. Thus desert regions