The third blessing give to humans is to have dominion over creation. This, of course, means a dominion of love and it manifests in various ways: manipulating nature (building dams for hydroelectric power, building windmills, agriculture, etc), creating new breeds of animals and varieties of plants, protecting endangered species, and so forth. One way that it manifests is in the human desire to understand nature. Scientists not only study the present, but also the past. In this respect, they have examined past geological times, and study fossils to better understand ancient life. Thus, the study of the Tertiary sub-era (formerly period), its geology, and its life.
Scientific knowledge is a developing process, and good science requires the ability to discard unworking theories and devise new theories. In the case of the Tertiary period, scientists once divided the known facts into the periods Primary, Secondary, Tertiary, and Quaternary. However, as new facts became known, scientists recognized that this artificial division was inadequate, and they did away with the Primary and Secondary periods, and now the Tertiary is falling into disfavor as well. Although students often are taught as if the scientific knowledge they are taught is absolute and unchanging, good science allows a development of ideas and new organization.