Do neutrinos oscillate from one variety to another?

As the concept of the neutrino has developed since the early 1930's, it has developed a split personality and put on weight. The neutrino is now thought to come in three varieties—electron neutrino, muon neutrino and tau neutrino. And a number of experiments are showing hints that a neutrino has a small mass and that it can oscillate from one variety to another. Taken alone, however, any individual experiment cannot be considered strong evidence of neutrino oscillations.