The anisotropy properties of the Cosmic Microwave Background Radiation (CMB) are considered within the framework of the photon beam mixing effect developed earlier. The existence of an observable characteristic of the CMB is shown, namely the geometrical shape of anisotropy spots and their degree of complexity, which can contain unique information on cosmological parameters and the life history of the Universe. If future experiments (COBE and others) indicate such features of anisotropy maps, then one can have serious evidence for the negative curvature of the Universe.