Chapter 15 Buss: Evolutionary Theory of Personality 455do is inherently beyond our conscious awareness, and this is particularly
true of evolutionary origins and strategies that shape our behavior. We are
no more aware of why we prefer sweet and fatty to bitter than we are of
why we are attracted to one person over another. Similarly, we have no idea
why we might be anxious and sensitive to stress while someone else is calm
and collected under duress.
In fact, one reason why people may resist evolutionary accounts of
behavior, much as they resisted Freud’s ideas, is that it makes the uncon-
scious conscious and people’s conscious ideas for why they do what they
do, like what they like, and are driven by what they are driven by are almost
always at odds with the evidence from science in general and from evolution-
ary psychology and biology in particular. And yet, we don’t have to be aware
of how eyes or hearts evolved in order to use them. We just use them.
Similarly, we just act, think, feel, and are motivated. Awareness is not neces-
sary and in many cases would be very disruptive.
The concept of humanity that will be most surprising to many people
will be evolutionary psychology’s stance on biological versus social influ-
ence. Clearly there is a strong emphasis on biological influences, from brain
systems, neurochemicals, and genetics. But as we have made clear in the
chapter, evolved mechanisms can only operate with input from the environ-
ment. Therefore, evolutionary theory is completely balanced on the question
of biological versus environmental causes of personality.
Evolutionary theory is also balanced on the question of the uniqueness
of the individual compared to general commonality among all people. The
structure of evolved mechanisms, that is, which mechanisms operate, are
species typical and universal, but the content of the mechanisms is unique
and shows tremendous differences between individuals.
Key Terms and Concepts
∙ (^) Artificial selection (otherwise known as “breeding”) occurs when
humans select particular desirable traits in a breeding species.
∙ (^) Natural selection is the process by which evolution happens and is
simply a more general form of artificial selection in which nature rather
than people select the traits.
∙ (^) Sexual selection operates when members of the opposite sex find certain
traits more appealing and attractive than others and thereby produce
offspring with those traits.
∙ (^) Adaptations are evolved strategies that solve important survival and/or
reproductive problems. Adaptations are often the products of natural or
sexual selection and must have a genetic or inherited basis to them.
∙ (^) By-products are traits that happen as a result of adaptations but are not
part of the functional design.