68 Unit 2 The Learner
When Bryson’s turn comes, he speaks loudly and confi dently, even when
he stumbles over words. Were Andre and Bryson born that way? Was
Andre taught to be shy by his shy parents, or is it a natural part of who he
is? If Andre was born with a tendency to be shy, would he have been more
outgoing if raised in Bryson’s family rather than his own?
This question has been debated over and over again. Is it nature (hered-
ity) or nurture (environment)? In other words, are a person’s personality traits,
abilities, skills, and tastes a result of genetics (what they were born with) or
a result of their environment (a person’s surroundings and the people in it)?
Most researchers today will answer “both.” It is not a matter of which, but
how large a part, each plays. How much did heredity affect Andre’s shyness
or Bryson’s outgoing personality? How much did the people around them
have an effect on them? Did their own experiences affect each child?
The challenge for researchers is that heredity and the environment
interact in complex ways. The genes a person has at birth have far-reaching
infl uence. They carry a person’s biological inheritance that determines
basics such as hair and eye color. Genes also impact intellectual potential
and much more.
Genetic predisposition even infl uences the kind of environment a person
seeks. For example, Bryson is sociable and outgoing. He enjoys being with
people. He loves to be around friends so much that when none are around, he
seeks one out. He makes friends quickly. In short, what children experience in
any environment is a personal response between their own genetic makeup
and the environment in which they develop. Shy adults tend to parent shy
children. However, a shy child can become a more outgoing person.
No single gene determines a particular behavior. Behaviors, like all
complex traits, involve multiple genes that are affected by a variety of envi-
ronmental factors. Genes do infl uence human development, but they are
just part of the story. Just because a person has the genetic makeup to have
a trait, it does not necessarily mean that a particular trait will develop.
How does environment infl uence development? A person is shaped by
his or her individual experiences. Social and emotional traits are affected
by the environment, but physical traits and cognitive abilities are, too. For
example, infants who are held and cared for develop more connections
between brain cells. The same is true of children who grow up in a stimu-
lating environment.
The term environment applies to many aspects of life. However, some
infl uence development more than others. As you read about those listed
here, think about how your life has been shaped by your experiences. Also
consider the impact your own words and actions have on others.
• Family. Families often have the greatest effect on human development.
It is in families that infants gain their fi rst experiences with the world
through the care and attention they receive. The bond between parent
and child is the most basic. Most children learn how to interact with