Figure 1.

Average depth of stratigraphic levels in Lamar Cave, number of modern (n = 7 specimens of T. t. tenellus and T. t. fuscus) and ancient specimens (n = 73) from Lamar Cave that were subjected to DNA analysis, respective age of the specimens, and summary of SSCP and sequence data. (A) The age-versus-depth curve for the deposits based on 18 calibrated radiocarbon dates with 95% confidence intervals shown (3). (B) Illustration of a lower left jaw with the measurements taken to analyze morphologic characters. (C) Changes in diastemal length (•) and toothrow length (□) for comparison with haplotypes A–C identified by SSCP analysis. We examined 88 ancient specimens spanning all 16 stratigraphic levels. In 73 cases (83%) we obtained a 164-bp PCR product of the mitochondrial cytochrome b gene (cyp b) 5′ end. Level 16 (2,400 to 3,000 years) did not yield any PCR product. The sample size column lists the number of specimens that were examined, and in parentheses, the number screened for 164 bp by using SSCP (first number), individuals directly sequenced for 63 bp (second number), and individuals cloned and sequenced for 134 bp (third number). Note: cloned individuals also have been sequenced directly with the exception of level 6. At level 7 morphologic change is most pronounced, coincident with changes in temperature and/or moisture regimes in the region.