Each bacterial species has a characteristic shape, but the benefits of specific morphologies remain largely unknown. To understand potential functions for cell shape, we focused on the curved bacterium Caulobacter crescentus. Paradoxically, C. crescentus curvature is robustly maintained in the wild but straight mutants have no known disadvantage in standard laboratory conditions. Here we demons...

A new method is described for interpreting image flow (or optical flow) in a small field of view produced by a rigidly moving curved surface. The equations relating the shape and motion of the surface to the image flow are formulated. These equations are solved to obtain explicit analytic expressions for the motion, orientation and curvatures of the surface in terms of the spatial derivatives (...