  The mode number of the Dirac operator scales with an exponent related to the
mass anomalous dimension gamma_m. This relation holds both in IR-conformal
systems, as well as in confining systems for large enough eigenvalues. We
investigate the Nf=4, 8 and 12 flavor SU(3) systems at several couplings near
the chiral limit, and show that in general the scaling exponent varies with the
eigenvalue, describing the dependence of gamma_m on the energy (or,
equivalently, on the running coupling). This energy dependence can be explored
even with fixed lattice parameters (bare coupling and mass). We find that for
the 4 flavor system the mass anomalous dimension decreases as the energy
increases, consistent with perturbative expectations. For the 8 flavor system
the energy dependence is too weak to be observable at present. The 12 flavor
system at our strongest couplings shows the anomalous dimension increasing with
energy, consistent with backward flow and the presence of an infrared fixed
point. At weaker couplings we determine a preliminary value for the mass
anomalous dimension of the 12 flavor system at the infrared fixed point,
gamma_m^*=0.27(3).
