  Fermion mass matrices generally rotate in generation space under scale
changes, which can lead to fermions of different generations transmuting into
one another. The effect is examined in detail and its cross-section calculated
for $\gamma + \ell_\alpha \longrightarrow \gamma + \ell_\beta$ with
$\ell_\alpha \neq \ell_\beta$ the charged leptons $e, \mu$, or $\tau$. For the
(conventional) Standard Model, this is weak and probably undetectable, though
with some notable exceptions. But for the Dualized Standard Model, which we
advocate and have already used quite successfully to explain quark mixing and
neutrino oscillation, the effect is larger and could be observable. Estimates
of transmutational decays are also given.
