  In this article, we explore the kinematics of timelike geodesic congruences
in warped five dimensional bulk spacetimes, with and without thick or thin
branes. Beginning with geodesic flows in the Randall--Sundrum AdS (Anti de
Sitter) geometry without and with branes we find analytical expressions for the
expansion scalar and comment on the effects of including thin branes on its
evolution. Later, we move on to congruences in more general warped bulk
geometries with a cosmological thick brane and a time-dependent extra
dimensional scale. Using analytical expressions for the velocity field, we
interpret the expansion, shear and rotation (ESR) along the flows, as functions
of the extra dimensional coordinate. The evolution of a cross-sectional area
orthogonal to the congruence, as seen from a local observer's point of view, is
also shown graphically. Finally, the Raychaudhuri and geodesic equations in
backgrounds with a thick brane are solved numerically in order to figure out
the role of initial conditions (prescribed on the ESR) and spacetime curvature
on the evolution of the ESR.
