‘Ceilidh (“cayley”) Dancing’ is an instability associated with the ‘active’ form of this phenomenon in biological nematics. Statistical field theories of this phenomenon can be studied with Wyld diagrams. One mean field closure to this phenomenon is the Local Energy Transfer approximation, which is consistent with a self-similar solution at low wavenumber. An energy spectrum of ‘k to the minus 5 (*) over 3’ in systems experiencing this phenomenon arises in the Kolmogorov (10[1])Cascade, (10[1]-5[1])where energy is dissipated at small length scales by viscous friction. The inertial form of this phenomenon arises due to the nonlinear term in the Navier-Stokes equation, causes eddies at many lengthscales, and occurs at high Reynolds numbers. Laminar flow is often contrasted with, for (10[1])10 points, which chaotic type of flow which can cause bumpy flights? ■END■