1. A biological specimen observation apparatus which observes temporal change in a biological specimen, comprising: an imaging device including a first objective lens and a second objective lens; and one or more processors, coupled to a memory, to control the imaging device to acquire a plurality of macro images of the biological specimen, by time lapse observation using the first objective lens, extract a biological change region from a macro image, among the plurality of macro images, by image analysis of the plurality of macro images of the biological specimen, and control the imaging device to acquire a plurality of micro images of at least a part of the extracted biological change region in the biological specimen, by another time lapse observation using the second objective lens.