Fig. 2.

Phytolith percentages from MP-A fine silt fractions. QB, Quebrada Bufeo (camp 1); MA, Medio Algodón (camp 2); and BA, Bajo Algodón (camp 3). The black bars on the y axis are charcoal dates and the category charcoal at the top represents charcoal volume (in cubic millimeters per cubic centimeter). If multiple charcoal samples fitted within a single depth-interval of one phytolith sample, then charcoal concentrations were averaged. The green bars on the y axis are phytolith dates. See also SI Appendix, Supplementary Text 3 for further description of phytolith types and frequencies.