CHAPTER XVIII. The Inheritance of Forms of Behavior

THE INHERITANCE OF FORMS OF BEHAVIOR

In a general way those peculiarities of behavior which suggested the name dancing mouse are inherited. Generation after generation of the mice run in circles, whirl, and move the head restlessly and jerkily from side to side. But these forms of behavior vary greatly. Some individuals whirl infrequently and sporadically; others whirl frequently and persistently, at certain hours of the day. Some are unable to climb a vertical surface; others do so readily. Some respond to sounds; others give no indications of ability to hear. I propose in this chapter to present certain facts concerning the inheritance of individual peculiarities of behavior, and to state the results of a series of experiments by which I had hoped to test the inheritance of individually acquired forms of behavior.

My study of the nature of the whirling tendency of the dancer has revealed the fact that certain individuals whirl to the right almost uniformly, others just as regularly to the left, and still others now in one direction, now in the other. On the basis of this observation, the animals have been classified as right, left, or mixed whirlers. Does the dancer transmit to its offspring the tendency to whirl in a definite manner?

Records of the direction of whirling of one hundred individuals have been obtained. For twenty of these mice the determination was made by counting the number of complete turns in five-minute intervals at six different hours of the day. For the remaining eighty individuals the direction was discovered by observation of the activity of the animals for a brief interval at five different times. Naturally, the former results are the more exact; in fact, they alone have any considerable quantitative value. But for the problem under consideration all of the determinations are sufficiently accurate to be satisfactory.

The distribution of the individuals which were examined as to direction of whirling is as follows.

RIGHT WHIRLERS LEFT WHIRLERS MIXED WHIRLERS TOTAL

Males 19 19 12 50 Females 12 23 15 50

The frequency of occurrence of left whirlers among the females is unexpectedly high. Is this to be accounted for in terms of inheritance? In my search for an answer to this question I followed the whirling tendency from generation to generation in two lines of descent. These two groups of mice have already been referred to as the 200 line and the 400 line. The former were descended from Nos. 200 and 205, and the latter from Nos. 152 and 151. Individuals which resulted from the crossing of these lines will be referred to hereafter as of mixed descent. There were some striking differences in the behavior of the mice of the two lines of descent. As a rule the individuals of the 200 line climbed more readily, were more active, danced less vigorously, whirled less rapidly and less persistently, and were in several other respects much more like common mice than were the individuals of the 400 line. It is also to be noted (see Table 5) that few of the litters of the 200 line exhibited auditory reactions, whereas almost all of the litters of the 400 line which were tested gave unmistakable evidence of sensitiveness to certain sounds. These differences at once suggest the importance of an examination of the whirling tendency of each line of descent.

The results for the several generations of each line which I had opportunity to examine are unexpectedly decisive so far as the question in point is concerned.

INDIVIDUALS OF THE 200 LINE

MALES FEMALES

First generation No. 200, ? No. 205, ? Second generation No. 210, Mixed whirler No. 215, Left whirler Third generation No. 220, Mixed whirler No. 225, Mixed whirler Fourth generation No. 230, Right whirler No. 235, Mixed whirler Fifth generation No. 240, Right whirler No. 245, Left whirler

INDIVIDUALS OF THE 400 LINE

MALES FEMALES

First generation No. 152, Left whirler No. 151, Left whirler Second generation No. 410, Left whirler No. 415, Right whirler Third generation No. 420, Left whirler No. 425, Left whirler

One line of descent exhibited no pronounced whirling tendency; the other exhibited a strong tendency to whirl to the left. Are these statements true for the group of one hundred individuals whose distribution among the three classes of whirlers has been given? In order to obtain an answer to this question I have reclassified these individuals according to descent and direction of whirling.

INDIVIDUALS OF THE 200 LINE

RIGHT WHIRLERS LEFT WHIRLERS MIXED WHIRLERS TOTAL

Males 7 6 8 21 Females 5 8 8 21 12 14 16 42

INDIVIDUALS OF THE 400 LINE

RIGHT WHIRLERS LEFT WHIRLERS MIXED WHIRLERS TOTAL

Males 4 9 1 14 Females 6 9 4 19 10 18 5 33

INDIVIDUALS OF MIXED DESCENT

9 10 6 25

Three interesting facts are indicated by these results: first, the inheritance of a tendency to whirl to the left in the 400 line of descent; second, the lack of any definite whirling tendency in the 200 line; and third, the occurrence of right and left whirlers with equal frequency as a result of the crossing of these two lines of descent.

It is quite possible, and I am inclined to consider it probable, that the pure dancer regularly inherits a tendency to whirl to the left, and that this is obscured in the case of the 200 line by the influences of a cross with another variety of mouse. It is to be noted that the individuals of the 200 line were predominantly mixed whirlers, and I may add that many of them whirled so seldom that they might more appropriately be classed as circlers.

THE INHERITANCE OF INDIVIDUALLY ACQUIRED FORMS OF BEHAVIOR

The white-black discrimination experiments which were made in connection with the study of vision and the modifiability of behavior were so planned that they should furnish evidence of any possible tendency towards the inheritance of modifications in behavior. The problem may be stated thus. If a dancing mouse be thoroughly trained to avoid black, by being subjected to a disagreeable experience every time it enters a black box, will it transmit to its offspring a tendency to avoid black?

Systematic training experiments were carried on with individuals of both the 200 and 400 lines of descent. For each of these lines a male and a female were trained at the age of four weeks to discriminate between the white and the black electric-boxes and to choose the former. After they had been thoroughly trained these individuals were mated, and in course of time a male and female, chosen at random from their first litter, were similarly trained. All the individuals were trained in the same way and under as nearly the same conditions as could be maintained, and accurate records were kept of the behavior of each animal and of the number of errors of choice which it made in series after series of tests. What do these records indicate concerning the influence of individually acquired forms of behavior upon the behavior of the race?

TABLE 53

THE INHERITANCE OF THE HABIT OF WHITE-BLACK DISCRIMINATION

Number of Errors in Daily Series of Ten Tests

MALES FEMALES

SERIES FIRST SECOND THIRD FOURTH FIRST SECOND THIRD FOURTH GENERA- GENERA- GENERA- GENERA- GENERA- GENERA- GENERA- GENERA- TION TION TION TION TION TION TION TION

No. 210 No. 220 No. 230 No. 240 No. 215 No. 225 No. 235 No. 245

A 6 5 6 7 8 4 4 7 B 6 8 8 8 8 7 6 5

1 6 7 6 5 7 6 5 4 2 4 3 1 5 5 6 4 5 3 3 1 4 5 3 4 4 3 4 5 0 3 4 2 1 3 1 5 3 0 4 2 1 3 3 0 6 2 1 4 2 2 1 1 1 7 1 0 3 1 1 1 2 0 8 0 0 1 0 0 0 2 3 9 0 0 0 1 1 0 0 0 10 0 0 1 0 2 1 1 11 0 0 0 3 0 0 12 0 0 0 0 0 13 0 0 0 0 14 0

I have records for four generations in the 200 line and for three generations in the 400 line. As the results are practically the same for each, I shall present the detailed records for the former group alone. In Table 53 are to be found the number of errors made in successive series of ten tests each by the various individuals of the 200 line which were trained in this experiment. The most careful examination fails to reveal any indication of the inheritance of a tendency to avoid the black box. No. 240, in fact, chose the black box more frequently in the preference series than did No. 210, and he required thirty more tests for the establishment of a perfect habit than did No. 210. Apparently descent from individuals which had thoroughly learned to avoid the black box gives the dancer no advantage in the formation of a white-black discrimination habit. There is absolutely no evidence of the inheritance of this particular individually acquired form of behavior in the dancer.

INDEX

Abnormal dancers. Acquired forms of behavior. Act, useless, repeated. Activity, periods of. Affirmation, choice by. Age, peculiarities; maximum age; and intelligence. Albino cat; dog. Alexander and Kreidl, young dancer; behavior; tracks of mice; behavior in cyclostat; behavior of white mouse and dancer; structure of ear; deafness. Allen, G. M., drawing of dancer; heredity in mice. Alleys, width of, in labyrinths. Amyl acetate for photometry. Anatomy of dancer. Animals, education of. Appuun whistles. Audition. See Hearing. Averages, dangers in.

Baginsky, B., model of ear of dancer. Bateson, W., breeding experiments. Behavior, of dancer; inheritance of; when blinded; equilibration; dizziness; structural bases of; of young; changes in; useless acts; under experimental conditions; in indiscriminable conditions; value of sight; in labyrinth experiments; modifiability of; history of; explanations of; individual differences in. Blinded dancers, behavior of. Blue-orange tests; blue-red tests; blue-green tests; blue-green blindness. Bradley papers. Brain, structure of. Breeding of dancers. Brehm, A. E., "Tierleben". Brightness vision; preference; check experiments; relation to color vision.

Cages for dancers. Candle meter. Candle power. Cardboards, for tests of vision; positions of. Care of dancer. Castle, W. E., drawing of mouse; cages. Cat, albino; training of. Cerebellum of dancer. Characters, acquired. Check experiments. China, dancers of. Choice, exhibition of; by affirmation; by negation; by comparison; methods of. Circling, a form of dance. Circus course mice. Cleghorn, A. G. Climbing of dancer. Cochlea, functions of. Color blindness. Color discrimination apparatus. Colored glasses. Colored papers. Color patterns of dancers. Color vision, problem; methods of testing; tests with colored papers, tests with ray filters, orange-blue tests, yellow-red tests, light blue-orange tests, dark blue-red tests, green-light blue tests, violet-red tests, green-blue tests, green-red tests, blue-green tests, blue-red tests, structure of the retina, conclusions, of different animals, Comparative pedagogy, Comparison, choice by, Cones, lacking in eye of dancer, Corti, organ of, in dancer, Cotton mouse, Curves, of habit formation, irregularities of, of labyrinth habit, of discrimination habit, of learning and re-learning, of plasticity, Cyclostat, behavior of dancer in, Cyon, E. de, dancer pathological, behavior, behavior of blinded dancers, varieties of dancer, space perception, individual differences, anatomy of dancer, hearing of dancer, pain cries.

Dancers, occurrence among common mice, varieties of, hybrid, Dancing, forms of dance movement, whirling, circling, figure-eights, manège movements, solo dance, centre dance, direction of, periods of, amount of, causes of, sex differences in, individual differences in, Darbishire, A. D., breeding experiments with dancers, Deafness of dancer, causes of, Descent, lines of, Development of young dancer, Differences, individual, sex, Direction of movement, choice by, Direction of whirling, Discrimination, visual, box, of brightness, white-black and black-white, of grays, habits, by odor, by form, method, habit defined, Diseases of dancer, Dizziness, visual, rotational, Docility, Dog, albino, training of, fear of electric shock.

Ear, structure of, structural types, model of, of rabbit, functions of, movements of, Educability of dancer, Education, human, methods of, of vision, Efficiency of training, Electric-box for visual tests, Electric-labyrinth for habit experiments, Electric-shock as punishment for mistakes, Epidemic among dancers, Equilibration in dancer, Error curves, form of, Error records versus time records, Errors, in labyrinths, nature of, types of, value of, number of, Even numbers to designate males, Excitability of dancer, Experience, value of, influence of, Eyes, of dancer opening of retina of

Fear, in dancer Females, designated by odd numbers dancing of voice of See Sex Fighting of dancers Figure eight dance Filters for obtaining colored light Food of dancer Form discrimination Frog, reactions of repetition of act by Functions of eye

Galton whistle Gestation, period of, in dancer Gray papers Green blue tests Green-red tests Grouping for averages Guaita, G von, breeding experiments with dancers

Haacke, W, description of dancer, origin of dancer breeding experiments Habit, of dancing, discrimination, useless labyrinth, duration of, reacquisition of, relations of, Habit formation, and the senses, versus habit performance, in the dancer and in the common mouse, curves of, speed of Habituation to sounds Hacker, dancing shrews Hair, appearance of Hamilton, G V, experiments with dog Hatai, S, the dancer Head, shape of, in dancer Hearing, in dancer in young in adult methods of testing, in frog Hefner unit of light Heredity See Inheritance Hering, E, colored papers History, of dancer of acts Hunger as motive in experiments Hybrid dancers

Imitation in dancer Index of modifiability Individuality Inheritance Inhibition of an act Initiative of dancer Insight of dancer Intelligence, measures of, comparisons Interrupted circuit for experimental use Irregular labyrinths

Janssen-Hoffman spectroscope Japan, dancers in Judgment in dancer

Kammerer, P, dancing wood mice, Kishi, K, dancer in Japan origin of race, equilibration, blinded dancer, structure of ear, wax in ears, tests of hearing König tuning forks, steel bars Kreidl, A See Alexander

Labyrinth, forms of, labyrinth A, errors in, tests, labyrinth B, tests, labyrinth C, labyrinth D, a standard labyrinth, regular and irregular labyrinths Labyrinth errors and individual tendencies Labyrinth habits, Labyrinth method, Labyrinth path, formula, method of recording, Ladder climbing tests, Landois, H, account of dancer, Lathrop, A, dancers, Learning, process, methods of in dancer, by being put through act, by imitation, by rote, rapidity of, permanency of, learning and relearning, curves of, Left whirlers, Life span of dancer, Light, reflected, transmitted, unit of measurement, control of, Litter, size of, in dancer, Lummer-Brodhun photometer.

Males, dancing of, fighting and killing young, designation of, voice of, See Sex Manège movements, Mark, E L, cages, Maze See Labyrinth Measurements, of light, of rapidity of habit formation, of intelligence, of efficiency of training, Memory, defined, for ladder climbing, tests of, measurements of, span of, for brightness, for color, Method, of studying dance, for testing hearing, indirect, for testing vision, motives, for brightness vision, for color vision, of shifting filters, of testing form discrimination, of testing Weber's law, development of methods, of choice, food box, labyrinth, of recording errors, of training problem method, labyrinth method, discrimination method, of recording labyrinth path, qualitative versus quantitative, of studying senses, values of methods, of measuring intelligence, quantitative, comparisons of, Milne-Edwards, origin of dancer, Mitsukun, K, the dancer in Japan, Mixed whirlers, Modifiability, of behavior, of useless acts, index of, Motives, for activity, for choice, avoidance of discomfort, in labyrinths, desire to escape, to get food, to avoid pain, Motor, tendencies, ability, capacity Movements, of ears, Mus musculus L, Mus spiciosus L, Mus sylvaticus L.

Nankin nesumi, name for dancer, Negation, choice by, Nendel, R, gray papers, Nerve, eighth, Nervous system, Nest materials, Noises, effects of, Numbers, odd for females, even for males, reference, See Bibliographic List.

Odors, discrimination by, Old Fancier's description of dancer, Olfactory sense See Smell Orange-blue tests, Orientation of dancer, Origin of dancer; by selectional breeding; by inheritance of an acquired character; by mutation; by pathological changes; by natural selection.

Panse, R., structure of ear; explanation of deafness. Papers, Nendel's grays; Bradley's colored; Hering's colored. Parker, G. H. Path in labyrinth, record of. Pathological condition of dancer. Pedagogy, comparative. Perception, of brightness; of color; of movement; of form. Peru, dancers in. Petromyzon, semicircular canals of. Photometer, Lummer-Brodhun. Plasticity of dancer; curves of. Position choice by, of cardboards. Preference for brightness, tests of. Preliminary tests. Probable error. Problems, of structure; of method. Punishment versus reward. Putting-through, training by.

Qualitative methods. Quantitative methods.

Rabbit, ear of. Rawitz, B., behavior of dancer; structure of ear; deafness of dancer; hearing in young. Ray filters. Reactions, to sounds; to disagreeable stimuli; valueless. Reasoning, implicit. Reconstruction method. Records, of markings of dancers; of time; of errors; of path. Red, stimulating value of; vision. Reference numbers to literature. See Literature on Dancer. Reflected light. Refrangibility and vision of dancer. Regular labyrinth. Re-learning, relation to learning; curves of. Reliability of averages. Repetition of useless acts. Rest-interval. Restlessness, of dancer; cause of. Retina of dancer. Retzius, ear of rabbit. Reward, for performance of act; versus punishment. Right whirlers; behavior in labyrinth; occurrence of; inheritance of tendency. Rods of retina. Rotational dizziness. Rubber stamps of labyrinths.

Saint-Loup, R. Schlumberger, C.; wood carving with dancers. Selenka, ear of rabbit. Semicircular canals. Sense organs. Senses, and habit formation; differences in. Sensitiveness Sex, recognition of, designation of, peculiarities Shellac to coat cards Shrews, dancing Sight, role of, See Vision, Brightness Vision, and Color Vision Smell sense of, in labyrinth habits Sniffing by dancer Solutions as ray filters Sorex vulgaris L Sound, reactions to Space perception Spectroscope Spectrum, stimulating value of Standard, candle, light, labyrinth Stine, W M, photometrical measurements Strength of dancer Structure, of brain, of ear, of eye Swinhoe, mice in China

Temperament of animal Temperature sense Tests, visual, number of, per day, Threshold of discrimination Time records Touch, and labyrinth habits Training conditions of, Weber's law, methods of, and retraining, in labyrinths, efficiency of, two test, ten-test, twenty-test, continuous, relation to methods, spread of Transmitted light.

Variability of dancer, Variable light. Varieties of dancer Violet red tests Vision, brightness vision, color vision, training of, importance of, conclusions concerning Visual dizziness Voice of dancer

Watson, J B, habit formation Waugh, K, color vision apparatus, retina of mouse Wax, plugs of, in ear of mouse Weber's law, tests of, apparatus Weldon, W F R, breeding experiments, Whirling of dancer

Yellow Red tests Young dancers, killing of, by male, description of, development of, hearing of, intelligence of, size of

Zoth, O, origin of dancer, size of young mice, the senses of dancer, behavior, dancing, equilibration, climbing dancers, individual differences, tests of hearing, vision