 The explanatory picture becomes more complicated by shifting away from SD as characterized by a positive global Lyapunov exponent and settling for what may be more realistic, namely the effects of divergence/contraction characterized by finite-time Lyapunov exponents. However, even in this case, it appears that the properties to which one appeals on a unification account pick out the patterns of chaos that we want to understand: How do these properties arise? It seems that unification accounts are still at a disadvantage in characterizing chaos explanations. 