Fig. 2.

Demographic history of the sheep population. (A) PSMC analysis results for the representative individuals sequenced at a high read coverage (∼42×) exhibit inferred variations in N_e over the last 10⁶ years. The N_e of mouflon, argali, ibex, dog, horse, and wild boar are also rescaled. The glaciation periods, atmospheric surface air temperature (°C) and global relative sea level data over the last 10⁶ years are included. (B) ∂_a∂_i analysis showing the demographic history of Chinese native sheep from ∼4,000 years ago to the present. Two population divergences occurred at 3,272 (t1) and 2,134 (t2) years ago. The average number of migrants per year between groups is shown between the black arrows. (C) Phylogenetic network of the inferred relationships among the 21 native breeds with three inter-group migration edges. The colored regions in the phylogenetic tree represent three inferred genetic groups. Arrows indicate migration events, and a spectrum of heat colors indicate the migration weights of the migration events. The scale bar shows 10× the average standard error of the entries in the sample covariance matrix. NEC, Northern and Eastern Chinese breeds; QT, Qinghai–Tibetan breeds; YK, Yunnan–Kweichow breeds. For the abbreviations of the breeds, see supplementary table S1, Supplementary Material online.