Figure 1: Single nucleotide divergence between macaque species/subspecies.

(a) Classification of single nucleotide divergence between macaque species. The ∼20 million single nucleotide differences among macaques were classified into three subclasses. The overlapping regions represent heterozygous variants shared between two individuals or all individuals. U, unique heterozygous variations evident in each species; F, the number of fixed homozygous variations in each species. (b) Single nucleotide divergence between macaque species in 100-kb windows across the genome. Heterozygous variants were ignored in this calculation. The divergence of X chromosomes between the two rhesus macaque subspecies was a significant outlier (P < 0.05, Grubbs' test). CE, crab-eating macaque; CR, Chinese rhesus macaque; IR, Indian rhesus macaque.