Readme file: December 12th 2011 The datafile is an excel spreadsheet that can be viewed with MS Excel or Open Office spreadsheet viewer or Numbers for Mac. There are three data sheets (tabs on the bottom) in this excel file. Each sheet contains genotype data for the named populations (Kerr, Bexar and Oklahoma) The format is that of typical microsatellite genotype data, which can be easily added into programs like GENALEX, and formatted into input files for a number of genetic data software. The genotype data is arranged as 1 population for each time point for that given population (refer to manuscript). For example, in Bexar, Pop 1 is the historical time point sample, where as Pop2 is the contemporary time point sample. Similarly for the other two populations. Here are the three populations and the time points from which samples are genotyped Kerr: 1900, 1910, 1915, 2005, 2007, 2008 Bexar: 1910, 2005 Oklahoma: 1910, 2005