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Rutberg, A. T. (1990). Inter-group transfer in assateague pony mares. Anim. Behav., 40(5), 945–952.
Abstract: Between-previous termgroup transfernext term of adult female previous termponies,next term Equus caballus, was investigated for three consecutive summers on previous Assateaguenext Island, Maryland, U.S.A. Both the previous terminternext term-band movements of individual previous termmares and the marenext term turnover rates of one-male “harem” bands were examined. Long-term previous termtransfersnext term occurred at rates ranging from 0·06 to 0·18 per previous termmarenext term per month. previous termMaresnext term with foals transferred more frequently than previous termmaresnext term without foals, but neither female age, pregnancy, nearest-neighbour distances nor dominance rank affected the likelihood of transferring. Band turnover rates were uncorrelated with the average frequency of previous termmare-marenext term aggression within the band, but new previous termmaresnext term entering a band suffered a transient rise in aggression received. Thus, female aggression did not encourage, and may have discouraged, previous terminternext term-band previous termtransfers.next term Older stallions and stallions who had held bands for 2 years or more had significantly larger and more stable bands. Fewer previous termmarenext term turnovers were seen in bands whose stallions tended to face their previous termmares,next term showed a relatively high proportion of time feeding, and showed a relatively low proportion of time involved in aggression with other stallions, although at marginal levels of significance for all three variables. Thus, variability in stallion attributes, and possibly behaviour, probably plays the strongest role in determining previous termmare transfernext term patterns at previous termAssateague.next term
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Janson, C. H. (1990). Ecological consequences of individual spatial choice in foraging groups of brown capuchin monkeys, Cebus apella. Anim. Behav., 40(5), 922–934.
Abstract: Individuals in a foraging group of brown capuchin monkeys choose different spatial positions relative to the rest of the group. An individual's choice of spatial positiion affects its foraging success and perceived predation risk (as measured by vigilance behaviour). The two most dominant group members preferred to forage where their expected forwaging success was greatest. Juveniles chose to forage where their perceived predation risk was least, not where they would achieve the highest foraging success. The positions used by non-dominant adults neither maximized foraging success nor minimized predation risk. It is likely that subordinate adults accept spatial positions with suboptimal ecological consequences to avoid the costs of frequent confrontations with the dominant members of the group over foraging sites in poreferred positions.
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Janson, C. H. (1990). Social correlates of individual spatial choice in foraging groups of brown capuchin monkeys, Cebus apella. Anim. Behav., 40(5), 910–921.
Abstract: Individuals in a foraging group of wild bronwn capuchin monkeys choose different spatial positions relative to the rest of the group. Markov analysis of sequencess of individual spatial positions demonstrated significant differnces between individuals, which coul be categorized a posteriori into four homogenous subgroups. An individual's spatial position was related primarily to the amount of aggression it received from the group's dominant male, but also varied with its sex. Spatial choice varied with changes in an individual's social status, but did not vary consistently with seasonal differences in food availability. These results support the hypothesis that individuals compete for preferred spatial positions within a foraging group.
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Pettifor, R. A. (1990). The effects of avian mobbing on a potential predator, the European kestrel, Falco tinnunculus. Anim. Behav., 39(5), 821–827.
Abstract: European kestrels were observed being mobbed by other birds on 63 occasions. Eleven species were involved, and in two instances mobs were composed of more than one species. Both flight-hunting and perch-hunting kestrels flew significantly further between their foraging positions when they were mobbed than when they were not mobbed; on average, mobbing resulted in flight-hunting kestrels moving 6[middle dot]8 times, and perch-hunting kestrels 2[middle dot]7 times, the mean distances moved by non-mobbed birds. The mean strike distance of perch-hunting kestrels attempting to capture birds was significantly less than the distance between perches flown by perch-hunting kestrels when mobbed. These data provide quantitative support for the assumption that mobbing causes a predator to vacate its immediate foraging area. The activity of the kestrels also influenced the frequency that they were mobbed, with kestrels that were flight-hunting being mobbed more than expected compared with ones that were perch-hunting. Kestrels were observed being mobbed throughout the year, and there was no discernible difference in their response to mobbing between seasons. These results are discussed in relation to current ideas on the functions of avian mobbing.
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Edgar, G. K., & Smith, A. T. (1990). Hemifield differences in perceived spatial frequency. Perception, 19(6), 759–766.
Abstract: Measurements of the perceived spatial frequency of stationary sinewave gratings were made with the gratings presented at the same eccentricity in the left, right, upper, and lower visual hemifields. Ten subjects performed the task binocularly with spatial frequencies of 1, 2, and 4 cycles deg-1. Two of these subjects also performed the task monocularly at 2 cycles deg-1. In the majority of cases, the spatial frequency of stimuli presented in the left and lower visual hemifields was overestimated relative to stimuli presented in the right and upper visual hemifields. The results were similar for all spatial frequencies tested, and the direction of the asymmetry was the same whether viewing was with the left eye, right eye or binocular, suggesting that the differences in perceived spatial frequency are not retinal in origin.
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Cheney DL, & Seyfarth RM. (1990). Attending to behaviour versus attending to knowledge: examining monkeys' attribution of mental states. Anim. Behav., 40, 742.
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Iacobucci, D., & Wasserman, S. (1990). Social networks with two sets of actors. Psychometrika, 55(4), 707–720.
Abstract: Abstract Traditional network research analyzes relational ties within a single group of actors: the models presented in this paper involve relational ties exist beteen two distinct sets of actors. Statistical models for traditional networks in which relations are measured within a group simplify when modeling unidirectional relations measured between groups. The traditional paradigm results in a one-mode socionatrix; the network paradigm considered in this paper results in a two-mode socionatrix; A statistical model is presented, illustrated on a sample data set, and compared to its traditional counterpart. Extensions are discussed, including those that model multivariate relations simultaneously, and those that allow for the inclustion of attributes of the individuals in the group.
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Potter, G. D., & Yeates, B. F. (1990). Behavioral principles of training and management. The Horse, 2nd Edn, , 665–682.
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Loyola, E. G., Rodriguez, M. H., Gonzalez, L., Arredondo, J. I., Bown, D. N., & Vaca, M. A. (1990). Effect of indoor residual spraying of DDT and bendiocarb on the feeding patterns of Anopheles pseudopunctipennis in Mexico. J Am Mosq Control Assoc, 6(4), 635–640.
Abstract: Intense and persistent use of DDT for malaria control has increased resistance and induced exophilic behavior of Anopheles pseudopunctipennis. An evaluation of bendiocarb and DDT to control this species in Sinaloa, Mexico, showed that, in spite of DDT-resistance, both insecticides produced similar effects. Feeding patterns were analyzed to explain these results. Resting mosquitoes were collected over the dry and wet seasons. Anophelines were tested in an ELISA to determine the source of the meals. The human blood index (HBI) ranged from 3.3 to 6.8% in DDT- and from 12.7 to 26.9% in bendiocarb-sprayed houses. Irritability and repellency in DDT-sprayed houses could explain the reduced HBI. In contrast, bendiocarb produced higher mortality. These effects could have affected different components of the vectorial capacity and similarly reduced malaria.
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Cuthill, I. C., Kacelnik, A., Krebs, J. R., Haccou, P., & Iwasa, Y. (1990). Starlings exploiting patches: the effect of recent experience on foraging decisions. Anim. Behav., 40(4), 625–640.
Abstract: Laboratory and field experiments have shown that, as predicted by the marginal value model, starlings, Sturnus vulgaris, stay longer in a food patch when the average travel time between patches is long. A laboratory analogue of a patchy environment was used to investigate how starlings respond to rapidly fluctuating changes in travel time in order to find out the length of experience over which information is integrated. When there was a progressive increase in the amount of work required to obtain successive food items in a patch (experiment 1), birds consistently took more prey after long than after short travel times; travel experience before the most recent had no effect on the number of prey taken. Such behaviour does not maximize the rate of energy intake in this environment. The possibility that this is the result of a simple constraint on crop capacity is rejected as, when successive prey were equally easy to obtain up until a stepwise depletion of the patch (experiment 2), birds took equal numbers of prey per visit after long and short travel times: the rate-maximizing behaviour. A series of models are developed to suggest the possible constraints on optimal behaviour that affect starlings in the type of environment mimicked by experiment 1.
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