Human females were further altered so that conception was possible not just once per year, but every 28 days. These questions, like many that mankind has asked, are fundamental to the learning process, and to spiritual growth. To ask why, is the first step in conquering ignorance. Evil is the condition that exists when good does nothing. Good is the light of creative action.
Evil is the darkness of inaction.
Where there is no good, there is only evil. Where there is no light, there is only darkness. This is a fundamental truth and must be understood fully before going any further. Long ago, those above tested that which is below. But for the finding of one good man, two cities and many people would have been saved.