The assessment of individual “Aggressiveness” in pigeons by a variety of means

Pigeons attack or threaten animate and inanimate targets. The assessment of their aggressiveness was studied by exposing them in their home cages to three different stimuli: the experimenter's hand, a live pigeon, and a rear-projected conspecific image when the birds were exposed to intermittent access to food. A positive correlation between the hand test and live pigeon test was evident, but no relationship between either of these responses and the response to a pictorial image was observed. These results combined with other ethological observations cast doubts on the usefulness of schedule-induced responses to pictorial targets in the assessment of the individual aggressiveness in pigeons, but suggest that the hand test is an adequate and reliable procedure for such evaluations.     

Effects of fluprazine (DU 27716) upon aggressive and sexual behavior of testosterone-treated female rats

Female rats, chronically treated with Testosterone Propionate (TP), were injected with Fluprazine (DU 27716) or saline and tested for social aggression, masculine and feminine sexual behavior. Fluprazine-treated females were less aggressive than saline-treated females, as indicated by a shift from offensive to less offensive parameters of aggression. At the same time, mounting in Fluprazine-treated females was almost totally abolished, both in aggression tests and in tests for sexual behavior. Feminine sexual responses increased during aggressive encounters but were slightly inhibited when females were confronted with sexually active males. Females treated with Fluprazine and tested for mounting with a receptive female showed a substantial increase of offensive aggression directed at the receptive stimulus female. It is concluded that Fluprazine does not selectively inhibit offensive aggression in TP-treated female rats.     

Various relationships between predatory dominance and aggressive behavior in Pairs of cats

The experiments were performed on adult male cats selected initially as good mousekillers. Cats were tested in pairs and each pair was introduced separately to the experimental compartment. The attitude toward the partner before and during the predatory competition test as well as superiority in catching and killing the mice, considered as an index of dominance, were registered. In the course of experiment five types of relations between the predatory dominance and aggressive behavior were observed. The concept of dominance as an outcome of several factors was discussed. It was concluded that predatory dominance is not based exclusively on aggressive mechanisms, as it may be formed and sustained without overt aggression.     

Taxonomies of aggressive behavior: A preliminary report

It has been widely and regularly suggested that aggression is not a unitary concept but rather an omnibus term concealing important and distinct subclasses of behavior. Psychologists have offered various categorical schemes highlighting motivation and form as distinguishing criteria. Many writers have also noted the social relativity of dermitions of classes of aggression and called for a consideration of lay conceptions of aggressive behavior. The present paper explores the correspondence between psychologists' and laypersons' categorizations of aggressive acts. Ten short scenarios of aggression were generated to embody systematic permutations of form and motive as suggested by the published work of social psychologists. Subjects rated every pairwise combination in terms of perceived similarity. The data were subjected to three-factor, multidimensional scaling. The resulting structure indicated that subjects' ratings were not random and reflected consideration of motive (hostile, normative, instrumental, status) and of direct versus indirect form. The data were thus in close correspondence with the classifications generated by psychologists. The desirability of refining this technique and extending it to other cultural and subcultural groups is discussed.     

The relation of prosocial behavior to the development of aggression and psychopathology

The development of prosocial behavior is traced from middle childhood to adulthood in a 22-year longitudinal study of 800 children first seen at age 8 and is compared to the development of aggression over the same period. Prosocial behavior and aggression seem to represent opposite ends of a single dimension of behavior since they are consistently negatively related to each other and relate in opposite ways to correlated variables both synchronously and over time. Both are stable forms of behavior with good predictability over the time span studied and both are related to the quality of the parent-child relationship. The most important deterrent to the development of antisocial behavior and the encouragement of prosocial behavior is probably a close identification between the child and his/her parents.     

Fear and aggression in the rat

The effect of fear on two types of aggression in rats was investigated by adding a cat stimulus to a colony in which the dominant male was attacking an intruder (offensive aggression), or, to a tube test situation in which defensive biting was measured before and during tail shock. The cat completely abolished offense in the colony; when the cat was presented and removed before a strange rat was placed in the colony, attack on the intruder was also reduced. In contrast, defensive biting was unchanged or even slightly potentiated by the presence of the cat, demonstrating a separation of the effects of fear on offensive and defensive aggression.     

Relative contributions of aggression and reproduction to behavioral endocrinology

Reproductive activity has been the behavior of choice for research in behavioral endocrinology. Why this is so and the consequences to the study of aggression and to behavioral endocrinology in general are explored.     

Do Positive Self-Perceptions Have a “Dark Side”? Examination of the Link between Perceptual Bias and Aggression

The hypothesis that positive self-perceptions may have a dark side was investigated in the present study by examining the relationship between positively biased self-perceptions and aggression. Ratings of actual and perceived social acceptance of third-grade (n = 278), fourth-grade (n = 260), and fifth-grade (n = 321) students were compared to form a measure of perceptual bias. Peers provided nominations for overt and relational aggression. Gender differences were found for aggression (males were more overtly and relationally aggressive than females) but not perceptual bias. African-American children held more positive perceptions of their social acceptance and were perceived by peers as more aggressive than Caucasian children. Even after controlling for the effects of gender and ethnicity, more positively biased perceptions were associated with more peer nominations for overt and relational aggression. Contrary to an optimal range of bias hypothesis, even moderately positive self-perceptions were associated with elevated levels of aggression.