Scientists dig up the history of the mole’s extra ‘thumb’
Marcelo Sánchez-Villagra from the University of Zurich and researchers have uncovered the evolutionary history of the mole’s extra “thumb.” As it turns out, this polydactyl animal evolved an elongated wrist bone to serve as a sort of extra finger, widening the paw for more effective tunneling. The researchers examined embryos of the Iberian mole (Talpa occidentalis) and the closely related—but…