DHFR and malaria: Taken together, using global alignment of the Pvdhfr haplotypes as representative of resistant DHFR homologs of geographically prone P. vivax parasites isolated from the GMS and other regions (Figure 3), the phylogenetic analysis of Pvdhfr haplotypes can explain (i) the migration or genetic flow of P. vivax parasites that is epidemiologically linked to two separate malaria ecotopes and (ii) the magnitude and geographical variation of emergent P. vivax haplotypes both within related malaria ecotopes and among diverse malaria ecotopes.