Models obtained by means of stepwise multiple regression analysis on factors that explained the variation of non-synonymous substitutions (Ka) and amino acid substitutions (Aa) (dependent variables) of pikas, rat and rabbit.

The independent variables were mean January actual temperature (Tjanu, °C) and altitude (Al, in m). Standardized (β) and nonstandardized (B) regression coefficients and their standard errors are shown. The table provides results from t-tests (t) and associated probability (P) levels.
Note: The survival environment of the standard trial animal, rat and rabbit, was according to the feeding conditions in laboratory (altitude = 500 m, temperature = 20°C).

本研究的自变量为1月平均实际气温（Tjanu，℃）与海拔高度（Al，m）。文中给出了标准化回归系数（β）、非标准化回归系数（B）及其标准误。该表格展示了t检验（t）的结果及对应的显著性概率（P）值。
注：标准实验动物（大鼠与家兔）的生存环境参照实验室饲养条件设置（海拔=500 m，温度=20℃）。