Besides starting surprisingly early, nurture also plays a surprisingly powerful role in our development. One example is studying the differences in identical twins; they have the same DNA, genes and biology; the same nature but they are different. It is amazing to me that so much of what we take for granted as being human (part of our nature) is actually learned from our environment (nurture). The video above is about a girl named Genie that was locked in a bedroom alone for 12 years of her life is one small piece of evidence of the power of social experiences on individuals. Here is what Susan Curtiss wrote about her in her book Genie; A Psycholinguistic Study of a Modern-Day Wild Child.
Genie was pitiful. Hardly ever having worn clothing, she did not react to temperature, either heat or cold. Never having eaten solid food, Genie did not know how to chew and had great difficulty in swallowing. Having been strapped down and left sitting on a potty chair she could not stand erect, could not straighten her arms or legs, could not run hop, jump or climb. In fact she could only walk with difficulty shuffling her feet and swaying from side to side. Hardly ever having seen more than a space of ten feet in front of her she had become nearsighted to exactly that distance....Surprisingly, however, Genie was alert and curious. She maintained good eye contact and...She was intensely eager for human contact.
You can also check out this website for examples of feral children. This website, though sad, provides further evidence for the importance of human nurturing in socializing individuals to their full human potential. How have you been shaped by the experiences of your life?