Figure 2.

Inferred losses of mitochondrial ribosomal protein and sdh genes among 280 angiosperms (species names are listed at www.bio.indiana.edu/∼palmerlab.html). Bullets indicate absence of hybridization to the probe in question. Numbers on the branches of the tree indicate inferred numbers of losses per internode. The three Gs indicate hybridizations scored as gains after ancient losses (see Results for explanation). Vertical names with brackets indicate plant orders. (A) Magnoliids (Bottom, Ceratophyllum and below), monocots (Middle, Acorus through Hordeum), and basal eudicots (Top, Dicentra and above). (B) Rosids (Middle and Top, Mytilaria and above) and basal eudicots (Bottom, Tetracentron and below). (C) Asterids (Middle and Top, Cornus and above) and caryophyllids (Bottom, Bougainvillea and below). The tree of the 280 examined angiosperms was constructed by consulting various recent molecular systematics studies. The following were the primary sources of interfamilial relationships: asterids (48) except for Lamiales (49), rosids and caryophyllids (50), basal eudicots (51), monocots (52), and magnoliids (53). Intra-familial relationships were based on various sources listed at www.bio.indiana.edu/∼palmerlab.html. rps10 data are from ref. 23. rpl2 data are for the 5′ portion of the gene (24). sdh3 and sdh4 data are from ref. 25.