of the orbital structure in the core galaxies and the fact that the transition from tangential to radial anisotropy is strongly correlated with the core radius ${r_b}$ provide an observational link between core formation and the population of central stellar orbits. Moreover, the core formation process must be very uniform to produce the observed homology in the distribution of core stellar orbits.

Adiabatic Growth and Core Expansion
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Tangential anisotropy in the core could be the result of adiabatic black hole growth [@Goodman84]. For two reasons, however, this process is unimportant for stellar orbits in core galaxies. First, the effect of adiabatic black hole growth on the orbital structure is weak and confined to the region inside ${r_\mathrm{soi}}$: the shaded area in Figure \[fig:intrinsic\](b) shows models of @Quinlan95. They start from an isotropic orbit distribution and initial central logarithmic density slopes of $\gamma=\{0,-1\}$. Even when the final black hole mass is up to 10% of the galaxy mass, the change in the central anisotropy remains modest ($| \Delta \beta| \le 0.3$; see also @Young80 and @Goodman84). If adiabatic black hole growth was the main driver behind the observed anisotropy in the cores of massive ellipticals, then the orbits would be 