The aggression test as a possible taxonomic tool in the Formica rufa group

The intra- and interspecific aggressive behavior of Formica polyctena, a species of the Formica rufa group, was analyzed and quantified both in the laboratory and in the field. This behavior was used as a potential taxonomic tool for gaining a better understanding of the phyletic relationships among the species within the group. No overt aggression was recorded toward members of the same species. To examine interspecific relationships, F. polyctena was first confronted with F. cunicularia, to ascertain its aggressiveness toward a distantly related species. All such encounters led immediately to overt and prolonged attacks with virtually no initial mutual inspection. This suggests that recognition of strangeness of the unrelated species is almost immediate in F. polyctena, as previously observed in F. lugubris and F. rufa toward the same antagonist. Subsequently, F. polyctena was contrasted with F. lugubris and F. rufa (also belonging to the F. rufa group) in order to compare these related species. Fierce attacks accompanied by all the elements of conflict behavior were observed in all encounters. Moreover, the degree of aggression in the field was higher than in laboratory-paired ants, possibly because of a territorial effect. These data and our previous and similar research indicate that the relationships between F. lugubris and F. rufa are closer than between these two species and F. polyctena. In considering different viewpoints on this problem, the validity of the aggression test is discussed and the opportunity to compare levels of aggressiveness among strictly sympatric samples of red wood ant species gathered from the same ecological environment are considered.     

Approach/Positive Anticipation,Frustration/Anger,and Overt Aggression in Childhood

ABSTRACT We examined mothers' ratings of children's affective and behavioral aspects of approach tendencies and links with overt aggressive behavior problems while considering the genetic etiology of these processes. Approach/positive anticipation (AP), frustration/anger (FA), and overt aggression in 4–9‐year‐olds were assessed using mothers' reports in a diverse national sample (n=992) and a sample of same‐sex twins (n=195 pairs). AP and FA were positively correlated with each other and with overt aggression (r from .2 to .5), and these associations were very similar for boys and girls. AP and FA provided overlapping as well as independent statistical prediction of aggression. AP statistical prediction of aggression was substantially mediated by FA, an effect that was accounted for by underlying genetic and nonshared environmental influences.     

Orthographic and Morphological Masked Priming Effects in Arabic: Evidence from Lexical Decision Task in Children with and Without Dyslexia

In this study, we conducted a lexical decision test using masked priming paradigm to examine the morphological and orthographic priming effects in word recognition. Morphologically related word pairs can be derivational, sharing the same root or not (pseudo derivational). However, the orthographically related pairs share the same letters in different positions. Two groups of native Arabic-speaking children (N?=?57) from grade 4 and 5 participated in this study: typical readers (n?=?39) and dyslexic readers (n?=?18). To examine whether a potential morphological priming effect is driven by semantic or orthographic properties of shared morphemes, we compared prime-target pairs with derivation morphology and pseudo-derivation word related pairs. Between groups comparisons showed that a priming effect occurred only in typical readers. Comparisons between conditions revealed that a priming effect only occurred for accuracy in derivational morphology. No priming effect occurred in reaction times (RTs) between groups or conditions. These results provide evidence for root-based word recognition in Arabic children and give support to semantically rather than orthographically driven lexical access.     

Intra- and lnterspecific aggression in two species of field crickets,Gryllus integer and G. alogus

Adult, laboratory-reared, and singly caged field crickets, Gryllus integer, of known ages and representing F1 to F4 generations, were exposed to 15–20-minute bouts of social interaction with introduced adult intruder males on alternate days from approximately 1 week after adult molt to time of death. A total of 3,523 paired-male bouts for 116 male G. integer were recorded over a 2.5-year study period. Adult males used as intruders were wild-caught or laboratory reared G. integer, but for nine of the 116 experimental males, wild-caught intruders of a closely related sympathetic species, G. alogus, were used for all or many of the bouts. Bouts between male G. integer and conspecific intruders were characterized by significantly elevated levels of aggression (t=6.04, P<0.001) compared with males exposed to heterospecific G. alogus intruders in interspecific interactions. Significant differences (p<0.005, chi-squared test of independence) existed at four out of five levels in a hierarchy of agonistic behaviors. Most G. integer males exposed to both G. integer and G. alogus intruders showed significantly reduced aggression levels during the interspecific interactions (p<0.001, Mann-Whitney U test). Conspecific G. integer dyads in the intraspecific interactions showed significantly stable dominant-subordinate relationships over time. Confusion surrounding the use of the term aggression is described with reference to Arthropods in general and Orthopteran insects in particular, and some likely proximate and ultimate bases for reduced interspecific aggression in field crickets are discussed.     

Does bullying others at school lead to adult aggression? The roles of drinking and university participation during the transition to adulthood

This study uses a three‐wave longitudinal study of young Australians to identify developmental processes underlying the relationship between school bullying and physical aggression in early adulthood. The central question is whether and how drinking and participation in work or university study disrupt or entrench aggressive pathways from school bullying to adult aggression. Self‐report data were collected from 88 females and 63 males (N = 151) during childhood (age 10), adolescence (age 14), and early adulthood (age 20). Participants who bullied other students during childhood and adolescence, or during adolescence only, reported more physical aggression during early adulthood than those who never bullied. However, those who had bullied during adolescence only reported significantly higher adult aggression if they were also drinking at above‐average frequencies. Conversely, participation in university, compared to being in the workforce, was associated with significantly less adult aggression among the at‐risk groups. Findings suggest that particular contexts during early adulthood can offer youth on aggressive trajectories (as evidenced by bullying at school) unique opportunities to turn their behaviour around. Other contexts, however, may exacerbate aggressive behaviour patterns.     

Weakly aggressive behaviour towards nymphs in the cockroach Schultesia nitor (Blattaria: Zetoborinae)

This paper describes aggressive behaviour in the cockroach Schultesia nitor, a tropical forest species living in bird nests. Young S. nitor nymphs are known to show active dispersal while old nymphs and adults are contrastingly strongly gregarious, a combination of features never observed in other cockroach species. Our laboratory experiments using video recording of confrontations between pairs show that aggressive behaviour towards conspecific nymphs is not exhibited towards nymphs of the species Phoetalia pallida, and thus can be considered species specific in S. nitor. But, it is not kin oriented: the mother and all adults of both sexes in different physiological states exhibit this behaviour as well. Six types of aggressive interactions were discriminated, occurring in age-symmetric pairs of nymphs and adults. Even more frequent aggression was exhibited by adults and last instar nymphs towards younger nymphs of all instars. The frequency of aggressive acts and types of aggressive interactions varied according to sex and size of the two interacting individuals. The possible function and evolution of this behaviour is discussed, with emphasis on the difficulty of interpreting obvious but weak and not kin-biased aggression.     

High maternal aggression in dwarf hamsters (Phodopus campbelli and P. sungorus)

The defense of offspring, termed maternal aggression, is a highly conserved behavior in mammals, including rodents. This study examined relative levels of maternal aggression in two closely related dwarf hamster species, Phodopus campbelli and P. sungorus, that normally inhabit high latitude, boreal environments. When tested with first litters and with the breeder male remaining with the female (for P. campbelli the male is necessary for successful rearing of offspring), both species exhibited high levels of maternal aggression with average duration of aggressive behavior>80 sec for a 10 min test. For P. sungorus, males are not required to rear offspring. P. sungorus females with either one or multiple litters (singly housed after impregnation) exhibited significantly higher levels of aggression (>300 sec) relative to females co‐housed with the sires. In terms of species differences in attack style, P. campbelli exhibited a boxing or clawing strategy for ～50% of total attack time, but for P. sungorus, this form of attack occurred<5% of the time. For P. sungorus, attacks to the vulnerable belly and flank constituted>90% of all attacks, but these regions were attacked ～50% of the time for P. campbelli. A survey of levels of maternal aggression of rodents in other genera suggests that maternal aggression in Phodopus is at the high end of the spectrum. Results of this study suggest that the presence of the breeder male may actually suppress aggression in P. sungorus. This fact, as well as its high level of aggression and its distant relationship to mice and rats, suggest P. sungorus as a possible model for future studies on the neurobiological basis of maternal aggression. The relationship between the high rates of maternal aggression and life history strategy in Phodopus is discussed. Aggr. Behav. 00:000–000, 2005. © 2005 Wiley‐Liss, Inc.     

Manipulations of vasopressin alter aggression differently across testing conditions in monogamous and non‐monogamous Peromyscus mice

Differences in the distribution of arginine vasopressin (AVP) and a subtype of AVP receptors, the V_1a receptor, may explain dissimilarities in social behavior of monogamous and non‐monogamous rodents. Intracerebroventricular infusions of AVP and a V_1a antagonist were used in sexually naive males of two mouse species, the monogamous and highly aggressive California mouse (Peromyscus californicus) and the non‐monogamous and less aggressive white‐footed mouse (P. leucopus), to begin testing the interaction between the social system of a species and the effects of AVP on aggression. Two testing conditions, the resident‐intruder aggression test (R‐I) and the neutral arena aggression test, were used because they may differ in function and underlying biological mechanisms. In the R‐I test, administration of the antagonist lengthened attack latencies in California mice. In contrast, blocking V_1a receptors did not alter attack latencies in the R‐I test in white‐footed mice or in the neutral arena aggression test in both species. AVP also did not alter aggression in either species in either behavioral test. Overall, these results suggest that AVP may be more likely to be associated with offensive aggression as measured in the R‐I test than with neutral arena aggression and that the effects of AVP manipulations may differ between monogamous and non‐monogamous rodents. Aggress. Behav. 31:000–000, 2005. © 2005 Wiley‐Liss, Inc.     

Sex differences in social representations of aggression: Men justify,women excuse?

Women tend to hold an expressive social representation of aggression (as a loss of self‐control) while men tend to hold an instrumental representation (as a means of imposing control over others). Because expressive beliefs correspond to excuses and instrumental beliefs to justifications, it may be a sex difference in moral acceptability of aggression that informs social representation. Participants completed the Expagg questionnaire with reference to an episode of same‐sex or cross‐sex physical aggression and rated the moral acceptability of their behaviour. Women scored higher on Expagg (specifically lower than men on the instrumental scale) but there was no effect of target sex or participant‐by‐target interaction. Contrary to expectation, women rated their own aggression as more acceptable than did men and hence this could not explain their lower levels of instrumentality relative to men. Aggr. Behav. 29:128–133, 2003. © 2003 Wiley‐Liss, Inc.     

Psychiatric nurses' attitudes towards inpatient aggression: preliminary report of the development of attitude towards aggression scale (ATAS)

Professional skills to adequately manage patient aggression are a prerequisite for nurses working in psychiatric hospitals. These ‘technical’ skills, however, are necessary but not sufficient for effective nurse intervention. The attitude of nurses' towards client aggression also contributes to their response to a patient's behaviour. In order to study the domains (types) of attitudes towards aggression, a sample was taken of nurses working in the fields of general psychiatry (n=288), psychiatry for children and adolescents (n=242) and psychogeriatrics (n=88). A cross‐sectional survey design was adopted for the study. The Attitudes Towards Aggression Scale (ATAS) consisting of 32 items is presented, representing three types of attitudes towards aggression: aggression as a ‘harming’ reaction, a ‘normal’ reaction and a ‘functional’ reaction. The strongest predictors of the type of attitude respondents had towards the aggressive behaviour of their clients were (1) field, (2) setting they worked in, (3) gender and (4) type of shifts they predominantly had. Although the measure of domains of nurses' attitudes towards aggression needs further psychometric testing, it can be a useful tool in clinical practice for the assessment of staff attitudes towards aggression. This can support the decision‐making about the management of aggressive behaviour on a ward. Aggr. Behav. 00:1–10, 2005. © 2005 Wiley‐Liss, Inc.     

Aggressive behavioral characteristics,hormones, and sexual orientation in men and women

Aggressive behavioral characteristics were assessed in groups of men and women by a self-report instrument, the Aggression Inventory, in which adult males reported more physical and verbal aggression than did females. Furthermore, males had higher scores on measures of impulsiveness and lack of frustration tolerance than did females, while women were more likely to avoid confrontation. In a second study, groups of male and female homosexuals and heterosexuals completed this Aggression Inventory after having blood samples taken to assay resting levels of testosterone (T) and estradiol (E). Groups of subjects within each gender were closely matched in terms of age, education, and vocational interests. Women were matched for the same time in their menstrual cycle (early follicular phase). Among men, homosexuals were indistinguishable from heterosexuals on all measures of aggression. Lesbians did not differ from heterosexual women on any aggression subscale except physical aggression, in which the homosexual women had lower scores. T and E were positively correlated with several indices of aggressive behavioral characteristics in men but were negatively correlated with those same measures in women.     

Does traffic congestion increase driver aggression?

In his recent article about aggressive driving, David Shinar proposed that the classical frustration-aggression hypothesis (Dollard, J., Doob, L., Miller, N., Mowrer, O. & Sears, R. (1939). Frustration and aggression. New Haven, CN: Yale University Press) provides a useful tool for understanding driver aggression (Shinar, D. (1998). Aggressive driving: the contribution of the drivers and situation. Transportation Research Part F, 1, 137–160). According to Shinar's (1998) application of the frustration–aggression hypothesis, driver aggression is caused by frustration because of traffic congestion and delays. In the present study, the relationships between exposure to congestion (rush-hour driving) and aggressive violations (DBQ) were investigated in Great Britain, Finland and the Netherlands. Partial correlations showed that the frequency of rush-hour driving did not correlate statistically significantly with driver aggression. Correlations between driving during rush-hour and aggression did not differ in magnitude from those between driving on country roads and aggressive violations. In addition, correlations between exposure to congestion and aggressive violations in countries with large number of vehicles per road kilometre (UK, Netherlands) were not higher than those in a sparsely populated country (Finland). These results from three countries suggest that congestion does not increase driver aggression as directly as suggested by Shinar (1998).     

Development of the Social Behavior of Two Mice Species With Contrasting Social Systems

The house mouse (Mus musculus) and the mound‐building mouse (M. spicilegus) differ in their mating and social systems. The M. musculus is polygynous and females tend to breed cooperatively while M. spicilegus is known to be monogamous and famous for its unique cooperative behavior; the communal overwintering. Mus spicilegus is considered as a highly aggressive species in the genus Mus. In the present study, we attempted to analyze the development of aggressive and sociable behavior in these species and to discover how familiarity with the target moderates the development of sociable and aggressive behaviors and moderates the differences between the species. Dyadic social interaction tests in neutral cages were performed on 21‐, 60‐, and 120‐day‐old mice of both genders and both species. Each individual was tested against a sibling and an unfamiliar individual at all three ages. Our results showed that the development of aggressive and sociable behavior with age differed between the species and sexes; however, familiarity with the other mouse moderated the effect of species on aggression. At 21 days, both genders of M. spicilegus were more aggressive against strangers than siblings. This became true of both species at 60 days. When facing a stranger, both sexes of M. spicilegus were more aggressive than M. musculus at 120 days. However, when facing a sibling, neither gender of M. spicilegus was more agonistic than M. musculus, indicating that either kinship or early social experiences elicit tolerance. Aggr. Behav. 38:288‐297, 2012. © 2012 Wiley Periodicals, Inc.     

Syrian hamster males below an age threshold do not elicit aggression from unfamiliar adult males

In many species, young males are the dispersers, leaving their natal area after weaning to establish a breeding area of their own. As young males disperse, however, they are bound to encounter unfamiliar adult males with established territories. Such interactions between an adult male and a young male may always be agonistic. Alternatively, there may be an age threshold below which aggression is not elicited and above which the adult male is aggressive toward the juvenile male. To test these two alternative hypotheses, we paired 47 young Syrian hamster (Mesocricetus auratus) males ranging from 24 to 65 days of age with 47 adult male hamsters and measured aggressive and investigatory behavior for 5 min. We observed no aggression by the adult toward young males between 24 and 47 days of age or toward the single male that was 49 days of age. Young males that were 50 days of age or older, however, elicited significant levels of aggression from the adults. These results indicate that in Syrian hamsters, young males are less vulnerable to adult aggression up to an age threshold and are more vulnerable to adult aggression beyond that threshold. This pattern may facilitate the establishment of territories by dispersing young males below that age threshold. Aggr. Behav. 37:91–97, 2011. © 2010 Wiley‐Liss, Inc.     

Fear of failure and student athletes’ interpersonal antisocial behaviour in education and sport

Background. The link between fear of failure and students’ antisocial behaviour has received scant research attention despite associations between fear of failure, hostility, and aggression. Also, the effect of sport experience on antisocial behaviour has not been considered outside of the sport context in adult populations. Further, to date, sex differences have not been considered in fear of failure research. Aims. To examine whether (a) fear of failure and sport experience predict antisocial behaviour in the university and sport contexts in student athletes, and whether this prediction is the same in males and females; and (b) sex differences exist in antisocial behaviour and fear of failure. Sample. British university student athletes (n= 176 male; n= 155 female; M_age= 20.11 years). Method. Participants completed questionnaires assessing fear of failure, sport experience, and antisocial behaviour in both contexts. Results. (a) Fear of failure and sport experience positively predicted antisocial behaviour in university and sport and the strength of these predictions did not differ between males and females; (b) females reported higher levels of fear of devaluing one's self‐estimate than males whereas males reported higher levels of fear of important others losing interest than females. Males engaged more frequently than females in antisocial behaviour in both contexts. Conclusions. Fear of failure and sport experience may be important considerations when trying to understand antisocial behaviour in student athletes in education and sport; moreover, the potential effect of overall fear of failure and of sport experience on this frequency does not differ by sex. The findings make an important contribution to the fear of failure and morality literatures.     

Calming an aggressor through spontaneous post‐conflict triadic contacts: Appeasement in Macaca tonkeana

Peaceful third‐party interventions usually occur after an aggressive encounter and can be directed toward the victim or the aggressor. Macaca tonkeana, a cercopithecine species characterized by high levels of tolerance, frequently engage in consolatory contacts, which both calm the victim and reduce the probability of further attacks against him/her. Other post‐conflict affiliative interventions such as reconciliation and quadratic affiliation are also common in this species. However, little attention has been given to contacts directed toward the aggressor. Here, we explore the role of bystander affiliative interventions toward the aggressor in influencing the affective state of the aggressor and the consequences of triadic interventions at group level. We found that triadic post‐conflict affiliation occurred independently from the intensity of the conflict and that it was more frequent in absence of the conciliatory contact between the opponents (reconciliation). Bystanders showed a higher amount of post‐conflict affiliation toward low ranking aggressors. Post‐conflict triadic affiliation functioned as a tension reduction mechanism by lowering the arousal of the aggressor, which less frequently engaged in renewed aggression. All these findings suggest that post‐conflict triadic contacts in Tonkean macaques can be considered as a strategic mechanism to calm the aggressor and reduce the risk of retaliatory aggression.

     

From marine ecology to crime analysis: Improving the detection of serial sexual offences using a taxonomic similarity measure

Jaccard has been the choice similarity metric in ecology and forensic psychology for comparison of sites or offences, by species or behaviour. This paper applies a more powerful hierarchical measure—taxonomic similarity (Δ_s), recently developed in marine ecology—to the task of behaviourally linking serial crime. Forensic case linkage attempts to identify behaviourally similar offences committed by the same unknown perpetrator (called linked offences). Δ_s considers progressively higher‐level taxa, such that two sites show some similarity even without shared species. We apply this index by analysing 55 specific offence behaviours classified hierarchically. The behaviours are taken from 16 sexual offences by seven juveniles where each offender committed two or more offences. We demonstrate that both Jaccard and Δ_s show linked offences to be significantly more similar than unlinked offences. With up to 20% of the specific behaviours removed in simulations, Δ_s is equally or more effective at distinguishing linked offences than where Jaccard uses a full data set. Moreover, Δ_s retains significant difference between linked and unlinked pairs, with up to 50% of the specific behaviours removed. As police decision‐making often depends upon incomplete data, Δ_s has clear advantages and its application may extend to other crime types. Copyright © 2007 John Wiley & Sons, Ltd.     

Effect of body size on aggression in the ant,Cataglyphis niger (Hymenoptera; Formicidae)

In polymorphic ants, such as Cataglyphis niger, sterile individual workers from the same nest show some degree of variation in size and/or morphology. We studied whether worker size and size difference between opponents had an effect on aggression during conspecific encounters. Although the capacity to recognize nestmates was shared by all individuals, some patterns of agonistic behaviors were size related. Escape was mostly displayed by the small workers, and threat, associated with ritualized fights, by the large workers. As game theory predicted, ants of C. niger adjusted their level of aggression as a function of the size of the opponent. However, only large individuals used such assessment strategies, responding with escalation of aggression towards small workers and reduction of aggression towards large ones. On the contrary, small individuals behaved in the same manner whatever the opponent's size. Differences between both morphological castes were discussed with reference to the resource holding assessment models. Aggr. Behav. 25:369–379, 1999. © 1999 Wiley‐Liss, Inc.     

High self-perceived social competence in rejected children is related to frequent fighting

High levels of aggression have long been assumed to be related to low self-esteem. Empirical studies have, however, never demonstrated any relation between low self-esteem and aggressive behaviour. Recently Baumeister and colleagues (1996 Baumeister, RF, Smart, L and Boden, JM. 1996. Relation of threatened egotism to violence and aggression: The dark side of high self-esteem. Psychological Review, 103: 5–33. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) proposed that aggressive behaviour does not result from low, but from unrealistically high self-esteem. They expect aggressive behaviour to occur when an unrealistically positive evaluation of oneself is disputed or threatened by others. In the present study Baumeister's proposition was tested for the domain of social acceptance in 179 third- and fourth-grade children. Self-esteem in the social domain was operationalized as self-perceived social competence, while threats to high self-perceived social competence were operationalized as rejection by peers. Participants completed the Dutch version of the Self-Perception Profile for Children and sociometric ratings of (dis)likeability and aggressiveness. Three rival hypotheses were tested: (1) the traditional hypothesis that aggressive behaviour is associated with low self-perceived competence; (2) the simplified hypothesis that aggressive behaviour is associated with high self-perceived competence; and (3) Baumeister's original hypothesis that aggressive behaviour is related to high self-perceived competence only when the latter is combined with less-favourable judgments from others. No support was found for the traditional hypothesis. Baumeister's original hypothesis was supported and explained more variance in aggressive behaviour than the simplified hypothesis.     

Exploration into the sources of individual differences in Aggression-, Hostility- and Anger-related (AHA) personality traits

In this study a behavior-genetic approach was used to identify sources of individual differences in Aggression-, Hostility- and Anger-related (AHA) personality traits (as measured with Spielberger's anger scales and scales from the Karolinska Scales of Personality), based on a sample (N = 140 individuals) that comprised of monozygotic twin pairs reared together (N_pairs = 26) or reared apart (N_pairs = 15), and dizygotic twin pairs reared together (N_pairs = 29). In general, the results suggest that environmental factors account for sibling similarity in hostility, whereas genetic factors account for sibling similarity in angry aggression and irritability (trait anger).