For the first time in the book, an attempt was made to determine the specific features of the environment of the ancestral home of mankind (rifts, earthquakes, volcanism, the richest deposits of uranium ores, etc.). The author suggests that the active manifestation of these features in the Pliocene, combined with geomagnetic inversions, created an area of ​ ​ increased radiation in East and Southern Africa. Irradiation caused mutations and changes in the structure of the body in the anthropoids living here (increase in brain volume, upright walking, disappearance of large fangs, etc.). The mutating foreman was expected to die if he had not switched to systematic social and labor activity.