Molecular Phylogenies Link Rates of Evolution and Speciation

Evolutionary biologists have sought a cor-relation between rates of genetic evolution and speciation ever since Mayr (1) pro-posed his founder-effect model of specia-tion; indeed this link formed the basis of the theory of punctuated equilibrium. Yet to date few correlations between net rates of speciation (speciation minus extinction) and genetic change have been demonstrated (2, 3), nor has an estimate of the generality of this relationship become available. We compared the net number of speciation events to underlying genetic change using 56 published phylogenies inferred from gene-sequence data (4), and we estimate