In both systems, using the conventional MSD has a major effect on the apparent motion of the molecules due to ignoring their motion along the axis perpendicular to the plane of the membrane. The magnitude of this effect is directly related to local orientation of the membrane segments, thus the projected displacements in the almost vertical regions of the "Wave" and "Budded" membranes underestimate the actual displacements the most. This phenomenon is purely geometric, and can have a significant impact on results obtained from experiments. The conventional MSD profiles (Figs. and, black lines) get progressively After surface meshing, all particle displacements, that is, initial and final particle positions (white circles) separated by a lagtime, ∆, are mapped onto the surface ensuring that both the starting and end point are on the mesh, as close to the origin as possible (gray circles).