The Dancing Mouse
and intelligence of animals may be studied. As it happens the dancer is an
ideal sub ject for the experiment al study of many of the problems of animal
behavior. It is small, easily cared for, readily tamed, harmless,
incessantly active, and it lends itself satisfactorily to a large number
of experimental situations. For laborat ory courses in Comparative
Psychology or Comparative Physiology it well might hold the place which
the frog now holds in courses in Comparative Anat omy.
Gratefully, and with this expression of my thanks, I acknowledge my
indebtedness to Professor Hugo M¨
unsterberg for placing at my command the
resources of the Harvard Psychological Laboratory and for advice and
encouragement throughout my investigation; to Professor Edwin B. Holt for
valuable assistance in more ways than I can mention; to Professor Wallace
C. Sabine for generous aid in connection with the experiments on hearing;
to Professor Theobald Smith for the examination of pathological dancers;
to Miss Mary C. Dickerson for the photographs of dancing mice which are
reproduced in the frontispiece; to Mr. Frank Ashmore for additional
photographs which I have been unable to use in this volume; to Mr. C. H.
Toll for the drawings for Figures 14 and 20; to Doctors H. W. Rand and C.
S. Berry for valuable suggestions on the basis of a critical reading of
the proof sheets; and to my wife, Ada Watterson Yerkes, for constant aid
throughout the experimental work and in the preparation of this volume.
R. M. Y.
CAMBRIDGE, MASSACHUSE TTS,
LIS T OF ILLUS TRA TIONS
LITE RA TURE ON THE DA NCING MOUSE
CHA RACTE RIS TICS, ORIGIN, AND HIS TORY
Peculiarities of the dancing mouse–Markings and method of keeping record
of individuals–The danc er in China and Japan (Kishi, Mitsukuri, Hatai)–
Theories concerning the origin of the race: selectional breeding; the
inheritance of an acquired character; mutation, inherit ance, and
selectional breeding; pathological changes; natural selection–Instances
of the occurrence of dancers among other kinds of mice–Results of
crossing dancer with other kinds of mice.
FEEDING, BREE DING, AND DEVELOPMENT OF THE YOUNG
Methods of keeping and caring for dancers–Cages, nest-boxes, and
materials for nest–Cleansing cages–Food supply and feeding–Import ance
of cleanliness, warmth, and pure food–Relations of males and females,
?ghting–The young, number in a litter–Care of young–Course of
development–Comparison of young of dancer with young of common mouse–
Diary account of the course of development of a typical litter of danc ers.
BEHAVIOR: DA NCE MOVEME NTS
Dancing–Restlessness and excitability–Signi?cance of restlessness–
Forms of dance: whirling, circling, and ?gure-eights–Direction of
whirling and circling: right whirlers, left whirlers, and mixed whirlers–
Sex di?erences in dancing–Time and periodicity of dancing–In?uence of
light on activity–Necessity for prolonged observation of behavior.