Genotyping procedures
For both species, a panel of 9-10 neutral microsatellite markers were amplified in the selected samples (Table S1) using a multiplex primary PCR followed by individual nested PCRs as previously described (Anderson et al., 2000; Jennison et al., 2015; Koepfli et al., 2013; Schultz et al., 2010). For P. falciparum , samples were genotyped at nine previously validated and commonly used, putatively neutral, microsatellite loci including TA1, TAA60, Polya, ARA2, Pfg377, TAA87, PfPK2, TAA81 and 2490 (Anderson et al., 2000; Schultz et al., 2010). For P. vivax , 10 putatively neutral microsatellites were genotyped as previously described: MS1, MS2, MS5, MS6, MS7, MS9, MS10, MS12, MS15 , and MS20 (Jennison et al., 2015; Koepfli et al., 2013). All PCR products were sent to a commercial facility for fragment analysis on an ABI3730xl platform (Applied Biosystems) using the size standard LIZ500. Primers used were the same for all datasets (Jennison et al., 2015; Schultz et al., 2010).