Figure 2. Phylogenetic relationship of all 154 intact Tas2r genes from 19 reptiles.

The western clawed frog (Xenopus tropicalis) V1R1 gene was used as an outgroup. The tree was reconstructed using the BI method with the best-fitting model of JTT+G+F. Branch lengths were drawn to the scale. Posterior probabilities from Bayesian inference analyses are presented in percent, in which the value of 100 was not shown. The detailed information about species, gene names and posterior probabilities was shown in Fig. S1. The NJ tree showing a similar topology to this tree was provided in Fig. S2.