The Mental Life of Monkeys and Apes

The Mental Life of Monkeys and
Apes - A Study of Ideational
Behavior

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Title: The Mental Life of Monkeys and Apes A Study of Ideational
Behavior
Author: Robert M. Yerkes
Release Date: January 27, 2004 [EBook #10843]
Language: English
Character set encoding: ISO-8859-1
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LIFE OF MONKEYS ***

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The Mental Life of Monkeys and Apes: A Study of Ideational Behavior
ROBERT M. YERKES Harvard University

BEHAVIOR MONOGRAPHS Volume 3, Number 1, 1916 Serial
Number 12 Edited by JOHN B. WATSON The Johns Hopkins
University

WITH SIX PLATES AND FIVE TEXT FIGURES

CONTENTS
I. Interests, opportunity and materials
II. Observational problems and methods
III. Results of multiple-choice experiments:
1. Skirrl, Pithecus irus 2. Sobke, Pithecus rhesus 3. Julius, Pongo
pygmaeus IV. Results of supplementary tests of ideational behavior:
1. Julius, _Pongo pygmaeus_: Box stacking experiment Box and pole
experiment Draw-in experiment Lock and key test 2. Skirrl, _Pithecus
irus_: Box stacking experiment Box and pole experiment Draw-in
experiment Hammer and nail test Other activities 3. Sobke, _Pithecus
rhesus_: Box stacking experiment Draw-in experiment Box and pole
experiment Other activities
V. Miscellaneous observations:
1. Right- and left-handedness 2. Instinct and emotion: Maternal instinct
Fear Sympathy
VI. Historical and critical discussion of ideational behavior in monkeys
and apes:
1. Evidences of ideation in monkeys 2. Evidences of ideation in apes
VII. Provision for the study of the primates and especially the monkeys
and anthropoid apes
VIII. Bibliography

I
INTERESTS, OPPORTUNITY AND MATERIALS
Two strong interests come to expression in this report: the one in the
study of the adaptive or ideational behavior of the monkeys and the
apes; and the other in adequate and permanent provision for the
thorough study of all aspects of the lives of these animals. The values
of these interests and of the tasks which they have led me to undertake
are so widely recognized by biologists that I need not pause to justify
or define them. I shall, instead, attempt to make a contribution of fact
on the score of each interest.
While recognizing that the task of prospecting for an anthropoid or
primate station may in its outcome prove incomparably more important

for the biological and sociological sciences and for human welfare than
my experimental study of ideational behavior, I give the latter first
place in this report, reserving for the concluding section an account of
the situation regarding our knowledge of the monkeys, apes, and other
primates, and a description of a plan and program for the
thorough-going and long continued study of these organisms in a
permanent station or research institute.
In 1915, a long desired opportunity came to me to devote myself
undividedly to tasks which I have designated above as "prospecting"
for an anthropoid station and experimenting with monkeys and apes.
First of all, the interruption of my academic duties by sabbatical leave
gave me free time. But in addition to this freedom for research, I
needed animals and equipment. These, too, happily, were most
satisfactorily provided, as I shall now describe.
When in 1913, while already myself engaged in seeking the
establishment of an anthropoid station, I heard of the founding of such
an institution at Orotava, Tenerife, the Canary Islands, I immediately
made inquiries of the founder of the station, Doctor Max Rothmann of
Berlin, concerning his plans (Rothmann, 1912).[1] As a result of our
correspondence, I was invited to visit and make use of the facilities of
the Orotava station and to consider with its founder the possibility of
coöperative work instead of the establishing of an American station.
This invitation I gratefully accepted with the expectation of spending
the greater part of the year 1915 on the island of Tenerife. But the
outbreak of the war rendered my plan impracticable, while at the same
time destroying all reasonable ground for hope of profitable
coöperation with the Germans in the study of the anthropoids. In
August, 1915, Doctor Rothmann died. Presumably, the station still
exists at Orotava in the interests of certain psychological and
physiological research. So far as I know, there are as yet no published
reports of studies made at this station. It seems from every point of
view desirable that American psychologists should, without regard to
this initial attempt of the Germans to provide for anthropoid research,
further the establishment of a well equipped American station for the
study not only