Chapter 15 Buss: Evolutionary Theory of Personality 431D
avid was a 17-year-old high school drop-out, arrested twice on drug charges,
and was working the night shift at a truck stop. One night a drunken driver
threatened to take an ax and chop off his long hair. Another night, a young man
beat David with a club for no apparent reason other than to start a fight. At this
point, David decided there must be a better way to make a living and so he enrolled
in night school to finish his high school diploma. After doing so, he got very lucky:
He won a random lottery to enter the University of Texas at Austin, for which he
did not have the required GPA. In college his intellectual curiosity blossomed. As
he put it, “In my junior year, I knew that I wanted to become a scientist and that
the human mind was the territory I wanted to explore” (D. Buss, 2004, p. 16). Ten
years later David was a professor of psychology at Harvard University!
How does a high school drop-out become a professor at Harvard? One of the
ideas that sparked this interest in learning and understanding in David was the con-
cept of evolution, especially when applied to human personality, thought, and behav-
ior. More specifically, it was his interest in sex and all the behaviors that go with
it—attraction, lust, jealousy, cheating, flirting, gossip—that focused his career ambi-
tions. This spark catapulted Buss from high school drop-out to Harvard professor.
To be fair, David was never a typical drop-out: His father was a distinguished pro-
fessor of psychology and his whole family was intellectually curious and talented.
Overview of Evolutionary Theory
Charles Darwin (1859) laid the foundation for the modern theory of evolution, even
though the theory itself has been around since the ancient Greeks. Darwin’s major
contribution was not the theory of evolution but rather an explanation for how evo-
lution works, namely through selection (natural and sexual) and chance. Chance
occurs mostly through random genetic mutation, and we won’t have much to say
about chance. Instead, we focus on selection of three different kinds.
In order to understand natural and sexual selection, let’s first examine a sim-
ilar concept created by humans and one that provided Darwin with his key insight:
artificial selection. Artificial selection (otherwise
known as “breeding”) occurs when humans select
particular desirable traits in a breeding species.
For example, the differences between the very
large Great Dane and the very small Chihuahua
have come about by humans selecting these qual-
ities in these breeds. Humans have been breeding
plant and animal species for thousands of years.
Natural selection is simply a more general
form of artificial selection in which nature rather
than people select the traits. More specifically, it
occurs when traits become either more or less
common in a species over long periods of time
because they do or do not lead to greater surviv-
ability (D. Buss, 1999; D. Buss & Greiling,
1999). In this way, natural selection involves
“evolved strategies” for a species’ survival. But
“Traits, such as size, are sometimes artificially selected for by
humans, and can lead to different breeds of dog.”
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