Mitochondrial DNA signifies that almost all fashionable dogs drop into one of four monophyletic haplogroups which might be named haplogroups A, B, C, and D. Many dogs fall in just haplogroup A. The mDNA "molecular clock" signifies that 22,800 YBP the initial genetic divergence (split) occurred in haplogroup A, causing the lineages A1b and A2. This