1. Introduction Angiosperms are the most diversified and widely distributed plant group in the cur- rent world. However, the origin and early history of angiosperms are poorly understood and controversial. Although paleobotanists have investigated much effort and applied various technologies to decipher ...
Molecular backbone constraints have been used previously to incorporate fossils within a molecular hypothesis in a number of different groups (e.g., snakes [63], turtles [64], old world monkeys [65], and leafy liverwort [66]), but this has never been performed before on cartilaginous fish....