BOOK REVIEW
An Inclusive Psychology
Valerie Kuhlmeier
Primate Psychology. Edited by Dario Maestripieri. xii + 619
pp. Harvard University Press, 2004. $65.
The history of the psychological study of primates begins with
Charles Darwin—who was, among other things, a comparative
psychologist. In The Expression of the Emotions in Man and
Animals (1872), Darwin examined and compared the facial
expressions of nonhuman and human primates, using zoo animals and
his son William Erasmus as his research subjects. Indeed, in The
Descent of Man, and Selection in Relation to Sex (1871),
Darwin argued for a psychological and behavioral continuity between
humans and animals, stating that "the difference in mind
between man and the higher animals, great as it is, certainly is one
of degree and not of kind."
In the essay that introduces Primate Psychology, editor
Dario Maestripieri notes that Darwin’s work, in turn,
influenced the research of eminent psychologists in the first half
of the 20th century. For example, Wolfgang Köhler looked for
"insight" in chimpanzees as they worked to overcome
obstacles to obtaining food. Robert Yerkes examined spatial
cognition and social behavior in captive primates at the laboratory
now named after him. And in the 1950s Harry Harlow investigated
infant maternal attachment in captive rhesus monkeys.
One might expect that, given this auspicious start, modern–day
psychology would be a field in which there is frequent dialogue and
collaboration between researchers in the nonhuman primate laboratory
and those across the hall who are studying human beings. But
Maestripieri, who is an associate professor of human development,
psychology and evolutionary biology at the University of Chicago,
suggests that although psychologists have made progress in this
direction, they need to be pushed further. In the 1970s, primate
behavior as an area of study within the field of psychology was, for
a time, sidelined, as advances in neuroscience led researchers to
focus instead on the study of brain anatomy. And why examine neural
pathways in primates when less expensive animals could be used to
model the human mind? Additionally, Maestripieri submits that the
absence of a strong theoretical focus—coupled with
questionable methodological rigor—led to the perception that
the psychology of nonhuman primates was not a "hard"
science. Indeed, the 1980s and early 1990s were particularly rough,
as funding continued to decline. Although some laboratories were
still quite proficient, it was generally difficult for students from
nonhuman–primate labs to succeed in the academic job market.
However, as the research presented in Primate Psychology
attests, times have changed. Maestripieri credits a resurgence of
interest in nonhuman–primate behavior and cognition to various
factors within psychology and related fields, including the emphasis
on mind–body interactions and the increasing attention paid to
the evolutionary origins of human cognition.
Why should we have an integrated nonhuman/human primate psychology?
Although Maestripieri is not the first to answer this question, he
does so convincingly. He points out that many psychologists today
recognize that the human brain, like other organs, has undergone
selective pressure, allowing our distant forebears to adapt to their
surroundings, thus ensuring their survival and reproduction. A
considerable number of these adaptations can likely be found in the
shared ancestors of modern human and nonhuman primates. Even though
we have drastically changed our environment through modern
technological advances, we still face a social milieu similar to
that of our early ancestors, one in which we must cooperate,
compete, attain food and access mates. Thus we can be expected to
share with nonhuman primates some of the adapted traits for
succeeding within those spheres; and it would be equally informative
to discover that we differ in significant ways. An inclusive primate
psychology would provide a richer understanding of both the human
and nonhuman mind, one in which the proximate causes and
evolutionary adaptive value of mental processes are considered.
The book contains 15 additional chapters by various investigators,
most of which review and discuss research on behavior and cognition
in both people and nonhuman primates. J. Dee Higley holds forth on
the neurological underpinnings of aggression, such as levels of
serotonin, cholesterol and testosterone, and Peter Judge covers
conflict resolution. Kim Wallen and colleagues discuss the social
and hormonal aspects of sexual behavior. Maestripieri, Lynn
Fairbanks and James Roney detail current research in attachment,
parenting and affiliation. In a chapter on cognitive development,
Jesse Bering and Daniel Povinelli discuss how chimpanzees and
children differ in their ability to make inferences about things
that cannot be directly observed, such as emotions, intentions and
gravity. Josep Call and Michael Tomasello sum up what is known about
the social insights of chimpanzees and what they do and don’t
understand about the mental states of others. Four chapters cover
various aspects of communication: nonvocal signals (Lisa Parr and
Maestripieri), vocal yet nonlinguistic calls (Michael Owren and
colleagues), the acquisition of language in nonhuman primates (Duane
Rumbaugh and colleagues), and the relation between brain asymmetries
and the evolution of language (William Hopkins and colleagues).
Samuel Gosling and associates discuss personality research as
applied to nonhuman primates, and Filippo Aureli and Andrew Whiten
examine emotions and behavioral flexibility. Finally, Alfonso Troisi
explores diagnostic criteria for psychopathology across primate
species, including humans.
There is little to criticize in this book. I especially recommend
Maestripieri’s excellent introduction, briefly summarized
above, to students and established researchers alike. The chapters
that follow focus on rich empirical findings in multiple areas of
research, each of which deserves its own specialized review.
Curiously absent, however, is the topic of numerical cognition, an
area of study in which researchers have recently demonstrated the
success that can come from collaboration and dialogue between those
studying human participants and those studying nonhuman primates.
Yet overall, the topics that are covered in this book
provide a good background for those interested in studying the
primary literature.
A lingering concern remains, though. One of Maestripieri’s
intended goals in Primate Psychology is to "encourage
communication between students of primate and human behavior."
Surely the book will not impede progress in this regard. It will
likely promote discussion and may have great effect on readers who
do research with human subjects. But given the title and the
close–up photograph of a gorilla’s face on the dust
jacket, the book is more likely to come to the attention of those
already studying nonhuman primates, which means that Maestripieri
will be largely preaching to the choir. To fully achieve the goal of
fostering better communication between the two camps, then, the onus
is on those of us in the choir to sing louder and to keep on
producing the type of rigorous, theory–driven science reported
in this book.—Valerie Kuhlmeier, Psychology, Queen’s
University, Kingston, Ontario