ddRAD of C. funebralis
Live animals (15 animals from each of 6 populations) were placed in 95% ethanol for 24 h, and then tweezers and scissors were used to take a tissue sample of each animalŐs foot. DNA was extracted using the Qiagen DNeasy kit.  ddRAD libraries were constructed following a protocol adapted from Peterson et al. (2012). Briefly, DNA was digested with the restriction enzymes MseI and XhoI, and six ddRAD libraries were constructed (one library for each geographic site). Each library was created by uniquely barcoding each of the 15 individuals from the respective site and then pooling these 15 individually barcoded samples. The libraries were run on agarose gels, and the 300Đ400 bp range was manually excised, purified and enriched with 12 amplification cycles in six individual PCRs. The six libraries were sequenced across two lanes of an Illumina HiSeq2000 (paired end, 2 x 100 bp) at the University of California Irvine Genomics High- Throughput Facility.