Using our HST/ACS observations of the recently found isolated dwarfspheroidal galaxies, we homogeneously measured their star formation histories.We determined star formation rate as a function of time, as well as age andmetallicity of the stellar populations. All objects demonstrate complex starformation history, with a significant portion of stars formed 10-13 Gyr ago.Nevertheless, stars of middle ages (1-8 Gyr) are presented. In order tounderstand how the star formation parameters influence the evolution of dSphs,we also studied a sample of nearest dSphs in different environment: isolated (d< 2 Mpc); beyond the Local Group virial radius (but within the Local Group zerovelocity sphere); and the satellites of M 31 located within the virial zone(300 kpc). Using archival HST/ACS observations, we measured their starformation histories. A comparative analysis of the parameters obtained allow usto distinguish a possible effect of the spatial segregation on the dSphsevolution scenario.