Smaller Voles: "Evolution in Action" Is Rare, Trivial

News from the University of Zurich is notable both for how underwhelming it is and for a "rare" admission. Researchers documented that as winter came earlier, snow voles got smaller. That seemed counterintuitive since, as the title of the publication in PLOS Biology asks rhetorically, "Bigger Is Fitter?"

Well, isn't it? Not so in this case, apparently. Why?

In principle, larger snow voles are fitter: They have better capabilities to survive and reproduce. Despite this positive correlation a...