Anomalous diffusion and non-Gaussian velocity distribution of Hydra cells in cellular aggregates

We study the center of mass motion of single endodermal Hydra cells in two kinds of cellular aggregates: endodermal and ectodermal. The mean square displacement displays anomalous super-diffusion with x2 tα where α>1. The velocity distribution function is non-Gaussian and fits well the q-distribution function of velocities within the framework of the non-extensive thermostatistics proposed by Tsallis. Our results indicate that cell motion in two-dimensional cellular aggregates can be described by a “correlated-type” anomalous diffusion.