66 Unit 2 The Learner
drive a car. An adult driver typically has fewer accidents than a teen because
years of practice and experience have improved his or her skills.
Development Is Interrelated
Most development is not solely physical, cognitive, social, or emotional.
Acquiring new skills typically requires gains in several of these areas. Think
about what it takes to become a skilled basketball player. You need physical
stamina, coordination, and endless practice to be able to hurl the ball precisely
into the hoop from any angle on the court. It also takes cognitive development
to learn plays and to fi gure out those of your opponents. You must be able
to judge the potential success of a shot. Socially, teamwork is required as is
the ability to “read” the intent of the player you are guarding. You will note
the body language and expressions of other players. Emotionally, you must
have confi dence, decisiveness, and perseverance. It takes all of these aspects of
development, and more, to play well.
Development Varies Among Individuals
Although development is orderly and predictable, each individual’s prog-
ress is unique. That is because so many factors affect development. No two
people—even twins raised together—have exactly the same experiences, 3-3.
Each individual faces life-changing experiences and responds to them based on
his or her personality, knowledge, and prior experiences. Everyone grows and
changes at a different rate and on a slightly different time schedule.
Theories of Development
You are waiting in the checkout line at the store when a small girl in
front of you starts screaming. Your natural reaction is likely to try to fi gure
out what caused the outburst. Is the child in pain, or is this a temper tan-
trum? Did her dad just tell her that she had to put back the candy bar she
picked up? The screaming continues. You listen for the father’s response.
Will he handle the situation well? Your opinions about why the situation
occurred and how well the parent responded are based on your current
knowledge and past experiences.
Researchers also analyze behavior and development to better under-
stand how and why it occurs. They may have more knowledge and experi-
ence and use more scientifi c methods, but the process is much like your
own. They observe people, perform experiments, and consider earlier
research studies. Then, they formulate their own explanations about why
people act and behave the way they do and how they change over time.
These are called developmental theories.