Aggressive interactions among female,semi-captive pampas deer (Ozotoceros bezoarticus) increase within the hierarchy and after short-term removal of the male

Two trials were carried out to determine: (a) if there is a positive relation between the frequency of aggressive interactions among female pampas deer and their position within the hierarchy (HI), (b) if short-term removal of the male triggers an increase in the frequency of aggression, and (c) if the magnitude of this increase is related to the individual rank position of the female. Each of 19 breeding groups comprised one adult male and from four to six adult females. The HI was determined for each female and all aggressive interactions were recorded. These were recorded while the male was present (i.e., all of Trial 1 and the “with male” period in Trial 2) and after removal of the male (i.e., the “without male” period in Trial 2). The individual percentage change in the frequency of aggressive interactions after male removal was calculated. In Trial 1 the HI, the frequency of different types of aggressive interaction and the total of aggressive interactions were positively related (all: p < .001; General Linear Mixed Model [GLMM]). In Trial 2, the frequency of total aggressive interactions increased after male removal (F(1, 27) = 3.5; p < .001; GLMM). The individual percentage changes in aggressive interaction between periods were positively related to HI (F(6, 24) = 2.56; p = .05; GLMM). For female pampas deer maintained in breeding groups, we conclude that the frequency of aggressive interactions increases within the hierarchy. Aggression also increases after the short-term removal of the male, mainly among females of higher social status.     

Experimental manipulations of social status and stress-induced cardiovascular responses in high and low trait dominant men

The present study investigated the effect of a mismatch between trait dominance and induced status on cardiovascular reactivity to and recovery from a dyadic interaction task. Eighty normotensive men characterized as either high or low in trait dominance engaged in a discussion requiring persuasive behavior either in the context of a high or low induced status position. The outcome of a rigged competition was used as a marker of status. Induced status was found to moderate cardiovascular recovery of dominance groups. High dominant individuals exhibited less complete recovery of diastolic blood pressure (DBP) when placed in a low compared to high status position, whereas recovery of low dominant individuals tended to show greater impairment in a high status position. Results for changes in emotional states also indicate a detrimental effect of incongruous status positions, particularly for high dominant individuals. Subjective experiences did not mediate cardiovascular effects, though.     

Rough approximation of pairwise comparisons described by multi‐attribute stochastic dominance

Given a finite set A of actions evaluated by a set of attributes, preferential information is considered in the form of a pairwise comparison table including pairs of actions from subset B⊂A described by stochastic dominance relations on particular attributes and a total order on the decision attribute. Using a rough sets approach for the analysis of the subset of preference relations, a set of decision rules is obtained, and these are applied to a set A\B of potential actions. The rough sets approach of looking for the reduction of the set of attributes gives us the possibility of operating on a multi‐attribute stochastic dominance for a reduced number of attributes. Copyright © 1999 John Wiley & Sons, Ltd.