Between the World Wars 71evolution. Attention was devoted to building an empirical
foundation for the field. The range of species studied was ex-
tensive. Although the study of learning came to be especially
prominent, there was much research on sensory function, de-
velopment, and social behavior as well. Although only a few
comparative psychologists studied animal behavior in the
field, many were aware of the place of their study subjects in
nature and used that awareness in understanding behavior.
Although the foundations for a stable field of comparative
psychology appeared to have been laid, it was not to be—at
least not yet. A number of problems arose. The major diffi-
culty lay in the place of comparative psychology, as a study
of behavior in animals, in psychology, a discipline most
viewed as the study of mind and behavior in humans. Despite
its intellectual and historical connections with the rest of psy-
chology, comparative psychology was perceived as a periph-
eral field. Pressures were brought to bear on those trained in
comparative psychology to switch and move to other re-
search areas, especially applied fields. At Harvard, for exam-
ple, Münsterberg (1911) wrote of Yerkes to President Abbott
Lawrence Lowell that “anyone interested in those animal
studies alone is in no way a real psychologist, and really no
longer belongs in the philosophy department.” The situation
was complicated because psychologists doing laboratory
studies of animals required special facilities that were both
expensive and viewed by some as undesirable because of
odor and atmosphere. Some had philosophical objections to
animal research. It became clear to many that the path to pro-
motion was to leave comparative psychology for applied
fields (Dewsbury, 1992). As a result, most comparative psy-
chologists educated during these years followed such paths
and left the field. The American entry into World War I and
the loss of personnel to military endeavors exacerbated the
situation.
BETWEEN THE WORLD WARS
The period running from the late 1910s and through the
1920s was a nadir for the field. With the old foundation for
the field gone, a new one had to be constructed.
Leaders of the Reconstruction
Few psychologists were in the universities to engage in re-
construction. Harvey Carr and Walter Hunter, products of the
Chicago program, remained active, as did Karl Lashley,
who was influential in the careers of many aspiring compara-
tive psychologists. After the war, Yerkes spent several years
in Washington before Angell, then the president of Yale
University, brought him to New Haven in 1924. Yerkes and
Lashley would be pivotal in the redevelopment of compara-
tive psychology that would help to establish it as a field that
has been strong ever since. Several other individuals who
would lead the reformulation of comparative psychology
were educated in other programs scattered about the country.
Although Yerkes functioned as an administrator in
Washington until 1924, he never lost sight of his plan for a re-
search station where nonhuman primates might be studied
(Yerkes, 1916). In 1915, he took a half-year sabbatical to
conduct research on primates in California. In 1923 he pur-
chased two animals, Chim and Panzee, for study, primarily at
his summer home in New Hampshire. The following sum-
mer, he studied primates in the colony of a private collector,
Madame Rosalia Abreu in Havana, Cuba. All the while, he
was publishing material on primate research (e.g., Yerkes,
1925) and lobbying various private foundations for funds for
a primate facility. Finally, in 1925 the Rockefeller Founda-
tion appropriated funds to support a primate facility in New
Haven and, in 1929, for a feasibility study for a remote pri-
mate station. Later that year, $500,000 was granted and
Yerkes established the Anthropoid Station of Yale University
(later renamed the Yale Laboratories of Primate Biology
when it was incorporated in 1935 and the Yerkes Laborato-
ries of Primate Biology upon its founder’s retirement). The
facility would remain in Orange Park until 1965 and was a
focal point of research on the great apes.
Lashley moved to the University of Minnesota in 1917
and, with an interlude of work in Washington, D.C., remained
there until he moved to Chicago, first to the Behavior
Research Fund of the Institute for Juvenile Research in 1926
and then to the University of Chicago in 1929. He moved to
Harvard University in 1935, and in 1942, he became the sec-
ond director of the Yerkes Laboratories of Primate Biology in
Orange Park, Florida, from which he retired in 1955.New Blood for Comparative PsychologyA cluster of comparative psychologists of lasting impact
completed graduate training during the 1920s and 1930s. Per-
haps the first of the new generation of comparative psycholo-
gists was Calvin P. Stone, who completed his PhD under
Lashley at Minnesota in 1921. Stone went on to a long career
at Stanford University, where he was noted for his studies of
sexual behavior and the development of behavior, for his ed-
itorial work, and for mentoring numerous students.
Zing-Yang Kuo, a native of Swatow, Kwangton, China,
completed a doctorate with Edward C. Tolman at the Univer-
sity of California at Berkeley in 1923. The primary issue
with which Kuo grappled during his career was the nature of