Despite the abundance of lithic debitage at preceramic sites in the Maya Lowlands, these data have rarely been studied in detail. We analyzed the chipped chert debitage from Caye Coco and Fred Smith, two Archaic period sites in the Freshwater Creek drainage of northern Belize, to evaluate strategies of lithic raw material procurement, stone tool production, and tool use. The technological and use-wear analyses of the debitage demonstrate that the sites’ inhabitants procured most of their tool stone from the Northern Belize Chert-bearing Zone (NBCZ) and relied on hard-hammer percussion to produce flakes for use as expedient tools and some crude bifaces and unifaces. Although similar patterns of raw material procurement and tool production are demonstrated at both sites, some differences exist, including bipolar reduction at Caye Coco. Based on use-wear analysis, the debitage at the island site of Caye Coco was primarily used for working wood, shell, and hard contact materials and for digging soil. On the shore at Fred Smith, most use-wear is consistent with working wood, plants, and hard contact materials, as well as digging soil. For both sites, analyses suggest the increasing importance of a horticultural subsistence strategy with reduced mobility and reliance on some cultigens that were locally produced.

For activity and survival in extreme terrestrial Antarctic habitats, lithobiontic cyanobacteria depend on key biomolecules for protection against environmental stress and for optimization of growth conditions. Their ability to synthesize such molecules is central to their pioneering characteristics and major role as primary producers in Antarctic desert habitats. Pigmentation is especially important in protecting them against enhanced UVB damage during stratospheric ozone depletion (the Ozone Hole) during the Antarctic spring and subsequent photoinhibition in the intense insolation of the summer. To be effective, especially for the screening of highly shade-adapted photosystems of cyanobacteria, protective pigments need to be located strategically. Antarctic lithic cyanobacterial communities are therefore stratified, as in soil biofilms of Alexander Island, the benthic stromatolitic mats of ice-covered hypersaline lakes in the McMurdo Dry Valleys, and the endolithic communities within translucent Beacon sandstone outcrops of Victoria Land. The protective pigments include scytonemin, carotenoids, anthroquinones and mycosporine-like amino acids. To detect and locate photoprotective pigments in situ in free-living cyanobacteria and cyanolichens from hot and cold desert habitats, we have used Fourier-transform Raman micro-spectroscopy. With appropriate power inputs for labile molecules, this high-precision, non-intrusive laser-based technique can not only identify biomolecules in their natural state but also locate them spatially within the habitat relative to the components of the community, which require protection. In conjunction with direct and epifluorescence microscopy it provides a spatial and functional description of the protective strategy of a community. We present the unique Raman spectrum of scytonemin and use its primary and corroborative peaks to identify it within the plethora of other biochemical constituents of several natural cyanobacterial communities, including an Antarctic endolith. The remote-sensing aspect of this technique makes it suitable not only for spatial biochemical analysis of present and palaeontological Antarctic communities but also for analogous putative habitats on Mars.