Biological Definition of Childhood
“Childhood” can be defined from a biological perspective as a period between weaning from the breast and the onset of puberty. Humans have the longest childhood of any mammal on the planet. How come? What is the benefit of a long childhood? The answer seems to be that children need that time in order to expand their potential before the onset of puberty.
Because puberty changes everything.
Dr Leonard Sax, in his book,Girls on Edge.
Image source can be found here.
black board, white chalk 
