贝叶斯支端定年法推断分异时间和演化速率

张驰

Using Bayesian tip-dating method to estimate divergence times and evolutionary rates

ZHANG Chi

图2 用于各个概率分布公式中参数的示例 树上化石F1和F2的特征状态为0,现生类群S1和S2的特征状态为1,内部节点的特征状态用x0, x1, x2表示化石的年代分别为t3 = 100 Ma, t5 = 50 Ma, 树根的时间为t1, 其他分异时间为t2和t4记t = {t1, t2, t3, t4, t5}。各个枝上的特征演化速率为r = {r1, r2, r3, r4, r5}

Fig. 2 Example parameters and symbols used in the probability distributions The character states for fossils F1 and F2 are 0, for extant taxa S1 and S2 are 1, for internal nodes are x0, x1, x2. The ages of fossils F1 and F2 are t3 = 100 Ma and t5 = 50 Ma The root age is t1 and the remaining divergence times are t2 and t4. Denote t = {t1, t2, t3, t4, t5}. The evolutionary rates on the branches are r = {r1, r2, r3, r4, r5}