It appears that the dynamical status of clusters and groups of galaxies isrelated to the large-scale structure of the Universe. A few interesting trendshave been established: (1) The Cluster Substructure - Alignment Connection, by which clusters show astrong correlation between their tendency to be aligned with their neighborsand their dynamical state (as indicated by the existence of significantsubstructres). (2) The Cluster Dynamics -Cluster Clustering Connection, bywhich dynamically young clusters are more clustered than the overall clusterpopulation. (3) The Cluster- Supercluster Alignment Connection, by whichclusters of galaxies show a statistical significant tendency to be aligned withthe projected major axis orientation of their parent supercluster. (4) TheGalaxy Alignment - Cluster Dynamics Connection, by which red-sequence clusterbright galaxies show a significant trend to be aligned with their parentcluster major axis, especially in dynamically young clusters. (5) The GroupRichness - Shape Connection, by which groups of galaxies are flatter the poorerthey are. These are strong indications that clusters develop in a hierarchical fashionby anisotropic merging of smaller units along the large-scale filamentarystructures within which they are embedded.
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