Median joining network of Ethiopian and Yemeni mtDNA haplotypes. Node sizes are proportional to haplotype frequencies, indicated within nodes for n>1. Haplotypes observed in Ethiopian and Yemeni samples are distinguished by pink and green, respectively. Variable positions (tables A1–A6 [online only]) are indicated along links that connect haplotypes. Nucleotide changes are specified only in the case of transversions. A, Network of haplogroups L0–L6. For haplotypes observed in the Yemeni population, matching HVS-I types in samples from northeastern Africa (Krings et al. 1999; Stevanovitch et al. 2004) and Mozambique (Pereira et al. 2001; Salas et al. 2002) are indicated by yellow and blue stars, respectively. B, Network of haplogroups M and N. For haplotypes observed in the Ethiopian population, matching HVS-I types in samples from northeastern Africa (Krings et al. 1999; Stevanovitch et al. 2004) and in the Arabian Peninsula and Iraq (Richards et al. 2000; Al-Zahery et al. 2003) are indicated by yellow and blue stars, respectively.