in determining how this inherited temperament expresses itself by the time
these uninhibited children become adolescents and adults.
EVOLUTIONARY PERSONALITY PSYCHOLOGY
Think for a moment about some recent experiences you have had with anxi-ety. That is, what happened to you the last two or three times you felt nervous,
worrisome, or anxious? Although direct threats to one ’s well-being —such as
an earthquake or physical assault —are certainly sources of anxiety, these
events are relatively rare for most of us and probably did not make your
list. Instead, if you are like most people, you probably thought of something
like talking in front of a group, making a fool of yourself at a party, orhaving a fight with a friend. In other words, you probably thought of at
least one situation that involved some sort of negative evaluation and possi-
bly even rejection by other people. Other situations on your list may haveonly suggested that some sort of negative social evaluation might be com-
ing, such as forgetting to turn in an assignment or discovering that you for-
got to use deodorant one morning. What this simple exercise illustrates isthat negative evaluation by other people, either directly or potentially, is a
common source of anxiety.
But why might this be the case? Is this a learned behavior? Do we fear
that others will punish us or refuse to give us something we want? That ’s cer-
tainly possible. Or could there be a psychoanalytic basis for this anxiety? At
some deep level are we reminded of a traumatic separation from our parents?
Perhaps. But another explanation suggests that the roots of anxiety go back
much further than this. According to this approach, we react to negative so-
cial evaluation in the same way our ancestors did. We inherited this tendency
to become nervous and upset in certain situations because experiencing this
anxiety has allowed humans to survive over many generations.
This different approach is known as evolutionary personality theory
(Buss, 1995, 1997, 2009; Buss, Haselton, Shackelford, Bleske, & Wakefield,1998). Proponents of this theory use the process of natural selection, bor-
rowed from the theory of evolution, to explain universal human characteris-
tics such as anxiety. These psychologists argue that many characteristics of
“human nature ”make sense if we understand the evolutionary function they
serve. We ’ll return to the example of anxiety later to illustrate this point. First,
we need to examine some of the assumptions underlying evolutionary person-ality theory.
Natural Selection and Psychological Mechanisms
Evolutionary personality psychology is based on the theory of evolution, as
developed in the field of biology for more than a century. According to evolu-tion theory, physical features evolve because they help the species survive the
challenges of the environment and reproduce new members of the species.
The key to this process is natural selection. That is, some members of a spe-
cies possess inherited characteristics that help them meet and survive the
threats from the natural environment, such as severe climate, predators, and
food shortages. These survivors are more likely than those less able to deal236 CHAPTER 9 The Biological Approach