fei75766_ch15_463-494.indd 489  02/24/20 10:48 AM
Chapter 15    Buss: Evolutionary Theory of Personality489
critics is that it is harshly deterministic in that it explains behavior in terms 
of an evolved past and genetic influence. Indeed, evolutionary psychology 
is often criticized for condoning traditional sex-roles (e.g., women are 
attracted to high status men and men are attracted to physically attractive 
women). Buss and other evolutionary theorists make clear, however, that 
evolutionary psychology is a theory of how these traits began, not how they 
should be. In other words, it is meant to be more descriptive than prescrip -
tive. Moreover, as we saw with Buss’s view of the origin of personality, 
biological and environmental explanations are not mutually exclusive. They 
are both necessary. Buss (1999) argues in fact that knowledge and aware -
ness of our evolved psychological mechanisms and strategies actually give 
us more power to change them if we want to.
On the question of causality versus teleology , it is clear that evolution -
ary theory comes down heavily on the causality side of the equation. Evolu -
tion by natural selection above all else is a theory of origins or cause. 
Darwin’s book, after all, was titled Origin of Species.
Evolutionary theory sides more with the unconscious influences  on 
thought, behavior, and personality than on conscious ones. Most of what we 
do 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, is spe -
cies typical and universal, but the content of the mechanisms is unique and 
shows tremendous differences between individuals.Final PDF to printer