Another example of the magic of fluid dynamics: laminar flow.
Laminar flow occurs when individual layers of a fluid remain distinct from one another even while undergoing motion. Laminar flow is observed within a specific regime or for a specific set of velocities (and momenta) of the fluid. The factors related to this specific regime of fluid dynamics depend upon the density and viscosity of the fluid.
What the makers of this video have done is made a cylindrical container which has a hollow region and within this hollow region is another cylinder. In the hollow region they’ve placed clear corn syrup and in order to demonstrate the non-mixing (non-diffusive, non-convective) nature of laminar flow they have placed three different colors of corn syrup at different radial points in the clear corn syrup. When they crank the inner cylinder they rotate the corn syrup within the regime of laminar flow. You can see the bands of died corn syrup spread around the cylinder.