  We conduct a systematic investigation of the nuclear collective dynamics that
emerges in systems with random two-body interactions. We explore the
development of the mean field and study its geometry. We investigate multipole
collectivities in the many-body spectra and their dependence on the underlying
two-body interaction Hamiltonian. The quadrupole-quadrupole interaction
component appears to be dynamically dominating in two-body random ensembles.
This quadrupole coherence leads to rotational spectral features and thus
suggests the formation of the deformed mean-field of a specific geometry.
