Fig. 3: A phylogenomic species tree of R. rugosa and eight other representative species.

This tree was constructed using 321 stringent single-copy nuclear protein-coding genes, showing gene family contraction and expansion. The numbers above the branches represent the number of gene families with either expansion (red) or contraction (blue). The numbers at the node indicate divergence time and 95% confidence interval. The species used in the tree are Arabidopsis thaliana, Fragaria vesca, Rosa chinensis, Rosa rugosa, Prunus persica, Malus domestica, and Pyrus bretschneideri. The red star indicates the whole-genome duplication in the ancestor of apple (M. domestica) and pear (P. bretschneideri)