The genealogy of Adam gives us a picture how from those being created in the image of God, were born new creatures. Male and female were created by the Only One God, Who blessed them and gave them the possibility to bring forth new blood, so that the purpose of God, to fill the world could be fulfilled.
The fifth chapter of the first book of the Pentateuch brings us the accounting of mankind. Moses gives an idea how the Children of God came one after the other on earth to play their role in history.
Study of geology over some centuries now has shown evidence of a succession of different eras represented by layers of rock giving evidence of the development of the earth over millions of years.