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Roberts, J., Hunter, M. L., & Kacelnik, A. (1981). The ground effect and acoustic communication. Anim. Behav., 29(2), 633–634.
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Barnard, C. J., & Sibly, R. M. (1981). Producers and scroungers: A general model and its application to captive flocks of house sparrows. Anim. Behav., 29(2), 543–550.
Abstract: Many forms of interaction within and between species appear to be based on `scrounger' individuals or species exploiting a limited resource provided `producers'. A mathematical model is presented which shows whether or not scroungers are maintained in a group, depending on their frequency and the group size. Some of the predictions of the model were tested in captive flocks of house sparrows Passer domesticus L. Here the scroungers obtained most of their food (mealworms) by interaction and the producers found most of their food by actively foraging: the pay-off to each type was measured as mealworm capture rate. Neither type changed strategy opportunistically in response to instantaneous flock composition but, not surprisingly, scroungers fared better when one of more producers were present. However, scrougers did much worse than expected when greatly outnumbered by producers, perhaps because producers then found the available food very quickly.
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Penzhorn, B. L., & Novellie, P. A. (1991). Some behavioural traits of Cape mountain zebras (Equus zebra zebra) and their implications for the management of a small conservation area. Appl. Anim. Behav. Sci., 29(1-4), 293–299.
Abstract: The social organisation of mountain zebras (Equus zebra zebra) consists of breeding herds (1 male, 2.4 females (range 1-5) and their offspring) which remain stable over many years, and bachelor groups. Foals leave their maternal herds of their own accord. In a free-ranging population the behaviour of the foals in leaving the herd is probably an adequate mechanism to prevent inbreeding, but inbreeding may occur in confined populations. Individual recognition by means of stripe pattern allows a check to be kept. Seasonal movement of mountain zebras is associated with a relative change in diet quality (as indicated by crude protein contents of preferred food plants and of faeces) between summer and winter habitats. Any conservation area should be large and varied enough to include both summer and winter habitats. Mountain zebras favour taller grass than most antelope species, harvesting their food at 50-150 mm from the ground. The existence of large populations of antelope could, therefore, be detrimental to zebras.
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Parker, G. A., & Rubenstein, D. I. (1981). Role assessment, reserve strategy, and acquisition of information in asymmetric animal conflicts. Anim. Behav., 29(1), 221–240.
Abstract: It was formerly argued that alternative evolutionarily stable strategies (ESSs) are possible for animal contests characterized by some asymmetry that can be perceived with perfect accuracy. Where roles A and B refer to the asymmetry between opponents, ESSs are: [`]fight when A, retreat when B', and vice versa. Either can be an ESS, but only if the [`]reserve strategy' (=what an animal does when it fights) is sufficiently damaging. We examine the [`]war of attrition' (winner = opponent that persists longer). In a population at either ESS, reserve strategy is never normally shown; it is therefore subject to drift unless the selective action of rare individuals which break the convention is considered. These could arise either by mutation or by mistakes in role assessment. When mutations and mistakes simply specify that occasionally an animal fights when it [`]should' retreat, selection adjusts reserve strategy to a level where only one ESS (the [`]commonsense' ESS) is possible, if the asymmetry is relevant to payoff. Thus for asymmetries in fighting ability or resource value, the individual with the lower score will retreat. However, we are particularly concerned with cases where both payoff-relevant aspects (fighting ability and resource value) are asymmetric. If opponents sustain contest costs at rates KA and KB, and their resource values are VA and VB, an [`]optimal assessor' strategy defined by the interaction between the two asymmetries, is a unique ESS. It obeys the rule [`]fight on estimating role A, where VA/KA>VB/KB; retreat in B'. If mistakes can occur in both roles, but are very rate, the ESS is not fundamentally altered though there will be infinitesimal tendencies for persisting in role B. Selection to improve assessment abilities intensifies as abilities improve, but is weak if roles A and B are rather similar. Over a range of similarity between roles, an [`]owner wins' convention may be adopted if ownership correlates positively with role A and an individual cannot tell when it would otherwise pay him to break the convention. We also examine a contest in which information about roles can be acquired only during a contest itself, and at a cost. Much depends on the rate at which information is acquired relative to the rate at which costs are expended, and on whether contests normally escalate in intensity, remain at the same level, or de-escalate. Selection favours short contests when costs are high relative to resource value, where the outcome of a round contains much information about fighting ability, and where the actual disparity in fighting ability is large.
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Powell, A. J., & Wolff, P. R. (1982). Sex differences in mouse urination patterns. Anim. Behav., 30(4), 1207–1211.
Abstract: When tested in circular open fields male and female mice (Mus musculus) produced strongly centrifugal urination patterns, which showed a clear `edge-dependency' in all the field sizes used. However, striking sex differences in the pattern of deposition were shown in terms of both the number and distribution of the urine spots. Male mice produce large numbers of spots which are regularly dispersed, while females produce relatively fewer spots with a more clumped distribution. It is suggested that a hitherto unsuspected level of intersexual communication may explain these differences.
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Salzen, E. A., & Cornell, J. M. (1968). Self-perception and species recognition in birds. Behaviour, 30(1), 44–65.
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Marinier, S. L., & Alexander, A. J. (1991). Selective grazing behaviour in horses: development of methodology and preliminary use of tests to measure individual grazing ability. Appl. Anim. Behav. Sci., 30(3-4), 203–221.
Abstract: Methods are described to assess horses' selective grazing ability that includes choosing, sorting and the adaptive value of this behaviour. Choosing ability was tested by the experimenter presenting pairs of cut plant species that were then alternated at each presentation until the test horse had taken three bites of one of the plant pair. The results were analysed in relation to five measures of choosing behaviour: (1) the strength of the choice; (2) correspondence between first bite and the final choice; (3) constancy of the choice over a number of trials; (4) the comparison of the horses' ranking of the species over a number of trials; (5) the constancy of the linear arrangement of the plants over a number of trials. Sorting ability was tested using two methods. A mixture of two plant species was presented either in a clamp or loose in a trough. Results were based on number and weight of plant residues. The adaptive value of the behaviour related to the bitterness of toxic plants. This bitterness was represented in testing by quinine sulphate and a poisonous Senecio species. An extremely bitter substance “Bitrex” was also used in this context but was totally accepted by the horses. The horses' reactions to these substances were monitored using a behavioural score chart. The results from 12 horses revealed that the horses differed individually in their grazing ability. On this basis, the horses were classified as efficient, semi-efficient, or inefficient grazers. This finding has practical implications in deciding which horses may safely graze on pastures infested with toxic plants.
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Boyd, R., & Silk, J. B. (1983). A method for assigning cardinal dominance ranks. Anim. Behav., 31(1), 45–58.
Abstract: Dominance hierarchies are widely described in nature. Commonly, an individual's ordinal rank is used as a measure of its position in the hierarchy, and, therefore its priority of access to resources. This use of ordinal ranks has several related drawbacks: (1) it is difficult to assess the magnitude or the significance of the difference in degree of dominance between two individuals; (2) it is difficult to evaluate the significance of differences between dominance matrices based on different behaviours or on the same behaviour at different times, and (3) it is difficult to use parametric statistical techniques to relate dominance rank to other quantities of interest. In this paper we describe a method for assigning cardinal dominance indices that does not suffer from these drawbacks. This technique is based on the Bradley-Terry model from the method of paired comparisons. We show how this model can be reinterpreted in terms of dominance interactions. and we describe a simple iterative technique for computing cardinal ranks. We then describe how to evaluate (1) whether the rank differences between individuals are significant, and (2) whether differences in the cardinal hierarchies based on different behaviours or the same behaviour at different times are significant. We then show how to generalize the method to deal with behaviours that sometimes have ambiguous outcomes, or behaviours for which the rank difference between a pair of individuals affects the rate of interaction between them.
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Caanitz, H., O'Leary, L., Houpt, K., Petersson, K., & Hintz, H. (1991). Effect of exercise on equine behavior. Appl. Anim. Behav. Sci., 31(1-2), 1–12.
Abstract: The effect of short periods of strenuous exertion, in this case treadmill exercise, on the subsequent behavior of Standardbred horses was examined. Six horses were exercised on a high-speed treadmill 4 or 5 days per week, for 3-4 miles (approximately 1.8 m s-1 for 3 min, 5 m s-1 for 12 min, 9 m s-1 for 3 min, 3 m s-1 for 3 min, 1.8 m s-1 for 3 min). The behavior of the horses was observed in the horse's home stall immediately after exercise and 2-7 h after exercise. Focal animal sampling for a total of 150 h revealed that the horses spent significantly more time drinking and less time resting after exercise than they did on control (non-exercise or rest days). The greatest influence on behavior was seen immediately after exercise. The horses spent 13.2+/-2.7 s per 15 min drinking after exercise and 7.2+/-2.3 s per 15 min drinking on non-exercise days. They spent 7.3+/-1.5 min h-1 stand resting after exercise and 9.7+/-2.1 min h-1 on non-exercise days. These changes in behavior may be related to the physiological changes that accompany exercise. Eating, walking, elimination and self-grooming were not significantly influenced by exercise. In a second experiment the activities of two groups of six Standardbred mares were compared. One group was exercised on the treadmill and the other was not. The exercised horses spent more time drinking and lying, but urinated less than the non-exercised group.
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Kabuga, J. D., Gari-Kwaku, J., & Annor, S. Y. (1991). Social status and its relationships to maintenance behaviour in a herd of N'dama and West African Shorthorn cattle. Appl. Anim. Behav. Sci., 31(3-4), 169–181.
Abstract: Social-related behaviour of N'dama and West African Shorthorn (WASH) cattle grazing together was studied over 10 consecutive days. Dominance was not related to age, liveweight or leadership when the animals were led into a weighing scale or into and out of the experimental paddock. Dominance had no influence on the use of shade, on drinking frequency or on grazing time, it was, however, positively associated with time spent ruminating and idling and with the frequency of allogrooming. Forced leadership into a weighing scale was negatively correlated (Spearmans rank correlation (rs=-0.69, P<0.05) with liveweight while voluntary leadership, out of the experimental paddock (rs=0.85, P<0.01) and into the experimental paddock (rs=0.76, P<0.05), was positively correlated with liveweight. Voluntary leadership also positively and significantly (P<0.01) influenced the frequency of visits to the water trough. All measures of leadership were significantly but negatively correlated with frequency of social association (close contact) between cows. N'dama were more aggressive than WASH and had higher dominance values. There was a slight tendency for WASH to associate more with their peers than N'dama with their peers. Social behaviours such as allogrooming were low and rubbing and sniffing absent in both breeds.
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