In the genus Macaca, the fourth month after birth is one of transition periods in mother-infant separation, and this separation is much promoted in the tenth month. This study was conducted to clarify the mother's and the ten-month-old infant's behavioral characteristics on the reunion after separation period for six month.
The subjects used in the study were twenty pairs of cynomolgus monkeys (Macaca fascicularis), ten pairs of mother and her own infant, and ten of mother and the other infant. The other infants were as old as own infants (Table 1).
Mothers' positive behavior to own infants in the moment of reunion was observed in seven mothers, and negative behavior was not observed. Positive or negative behavior to the other infants were observed in two or six mothers respectively (Table 2). Mothers' threat was tend to occur more frequently to the other infants than to own infants (Fig. 1), and occur vigorously from the first of the reunion to the other infants (Fig. 2).
In own infants, dangling to the top of the cage was less and food-taking behavior was more than those in the other infants (Fig. 3). It seemed that the other infants tend to take more time to get familiar with mothers than own infants. Fear-grimace and lip-smacking of the other infants were more frequent than those of own infants, and these behavior occur more frequently in female than in male (Fig. 4).
These results show that in cynomolgus monkeys, mothers can distinguish their own infants from the other infants even after separation period for six months, and that in behavior patterns to mothers at the moment of the reunion, there are differences between own infants and the other infants, also between male and female.

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104 ddY mice had been reared in two conditions since weaning. 48 animals were group-reared with 4 to 6 animals pergroup, whereas 56 were isolation-reared. 9 weeks after rearing, encounter tests were conducted at which four unfamiliar animals from the same rearing condition were simultaneously released at the four corners of a square open-field. Their social behaviors listed in Table 1 were observed by the random scanning method for twenty minutes.
The results indicated that the isolation-reared animals rarely showed the behavioral sequences of “Sniff 1 (sniffing others in one way) → Allogroom→ Genital-sniff” and “Attack→ Upright” (Fig. 1). As a whole the isolated animals showed more attacks, Fights, and less Grooms, Genital-sniffs and Sniff 1s than the group-reared animals did (Fig. 2). Looking at the results of the group-reared animals in more detail (Fig. 3), it was noticed that in most cases when Attacks occurred only the first-ranked animals (Rank 1) exclusively did Attacks following little or no Fight. The median value of Attacks showed by the group-reared Rank 1 animals was not less than that of the isolated animals. However, the most noticeable characteristics of the group-reared mice was their constant Grooms and Genital-sniffs whether of not they engaged in a high amount of Attacks.
Considering the effect of isolation on aggression it would be difficult to conclude that isolated animals are more aggressive than group-reared animals from the results of the four animals encounter test the authors used. The clearest effect of isolation seems to be the lack of Allogrooms and Genital-sniffs which are necessary to regulate social relationships. This proves that isolated animals lack social communication skills. In other words, these social behaviors need to be learned in social contexts so as to be used skillfully.

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[in Japanese]

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The effects of dimensional control to compound stimuli have been investigated from many viewpoints in the pigeon. In the goldfish, however, little is known directly about some control of responding by dimension that comprise a compound stimulus.
The present study was concerned with the characteristics of the two-dimensional control in the goldfish. The study employed wavelength as one stimulus dimension and a visual-spatial dimension, angular orientation of a band of light, as the second dimension. After the single-stimulus training with a compound stimulus, the subjects were tested for generalization along two dimensions.

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[in Japanese]

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