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Thouless, C. R., & Guinness, F. E. (1986). Conflict between red deer hinds: the winner always wins. Anim. Behav., 34(4), 1166–1171.
Abstract: Dominance relations between free-living, female red deer (hinds) (Cervus elaphus L.) on the Isle of Rhum, Scotland, were investigated. Most interactions were won by the older hind of the pair and this was the case even when both individuals had reached full body size. The younger hind was more likely to be the winner if the conflict was escalated or if the two hinds were strangers, in which case escalation was more frequent than usual. When outside their normal home range, older hinds were much more likely to lose, and younger ones more likely to win, than usual. These results can be best explained by the hinds using previous experience as a cue for conventional resolution of conflict, with the result that dominance relationships established early in life are perpetuated. No such cue is available if the hinds have not previously met.
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Frank S. A. (1996). Policing and group cohesion when resources vary. Anim. Behav., 52, 1163–1169.
Abstract: The transition from competing individuals to cooperative groups has occurred several times inevolutionary history. The puzzle is why selfish individuals did not subvert cohesive group behaviour bytaking resources without contributing to the group’s overall success. Kin selection and reciprocal altruism are the two standard explanations for group cohesion. But many groups have evolved into
cooperative units when relatedness was low and opportunities were limited for the strategic alliances required for reciprocity. A new theory was recently proposed in which individuals invest some of their resources into repressing competition between group members. Such policing increases the fair distribution of resources in the group and enhances group cohesion. The surprising aspect of this theory
is that low relatedness is more conducive to the spread of policing traits than is high relatedness. Here a new explanation is developed of the biological processes that favour policing. The model is then extended in two ways. First, more realism is added to the theory by accounting for the full range of costs and benefits associated with competitive and cooperative traits within groups. Second, another
surprising result is introduced about cooperative evolution. Small variations in individual vigour or resources can lead to large variations in individual contributions to policing the group. Stronger individuals often invest all of their excess resources into policing, but weaker individuals do not contribute to group cohesion.
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Dunbar, R. (2003). Evolution of the social brain. Science, 302(5648), 1160–1161.
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Leliveld, L. M. C. (2019). From Science to Practice: A Review of Laterality Research on Ungulate Livestock. Symmetry, 11(9), 1157.
Abstract: In functional laterality research, most ungulate livestock species have until recently been mainly overlooked. However, there are many scientific and practical benefits of studying laterality in ungulate livestock. As social, precocial and domestic species, they may offer insight into the mechanisms involved in the ontogeny and phylogeny of functional laterality and help to better understand the role of laterality in animal welfare. Until now, most studies on ungulate livestock have focused on motor laterality, but interest in other lateralized functions, e.g., cognition and emotions, is growing. Increasingly more studies are also focused on associations with age, sex, personality, health, stress, production and performance. Although the full potential of research on laterality in ungulate livestock is not yet exploited, findings have already shed new light on central issues in cognitive and emotional processing and laid the basis for potentially useful applications in future practice, e.g., stress reduction during human-animal interactions and improved assessments of health, production and welfare. Future research would benefit from further integration of basic laterality methodology (e.g., testing for individual preferences) and applied ethological approaches (e.g., established emotionality tests), which would not only improve our understanding of functional laterality but also benefit the assessment of animal welfare.
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Cloutier, S., Newberry, R. C., Honda, K., & Alldredge, J. R. (2002). Cannibalistic behaviour spread by social learning. Anim. Behav., 63(6), 1153–1162.
Abstract: We hypothesized that social learning is involved in the spread of cannibalism in domestic fowlGallus gallus domesticus . To investigate this hypothesis without harming birds, we used an inanimate chicken model as our cannibalism stimulus. We randomly assigned flocks of 12 White Leghorn pullets to one of two treatments: (1) flocks with two trained demonstrators (N=9) and (2) control flocks (N=8). Demonstrators were trained to pierce a membrane covering a dish of chicken blood and consume the blood. To assess the effect of access to the cannibalism stimulus during demonstrations, we randomly assigned observer pairs to one of two observer treatments: (1) observe stimulus through a wire mesh partition and (2) observe stimulus within the same enclosure. We conducted five 10-min demonstration sessions, each followed by a 10-min test of each observer pair in the absence of demonstrators, over a period of 15 days when the birds were 41-55 days of age, and two further tests at 63-64 and 91-92 days of age. Pairs that observed demonstrators piercing a membrane and consuming blood were more likely to perform this task when tested than control pairs. Learning of the task was enhanced by direct access to the cannibalism stimulus rather than observing it through a wire mesh partition. Blood consumption during tests was increased by direct access to the cannibalism stimulus during demonstration sessions. The birds made bigger holes in the membrane when tested after observing trained demonstrators and after having direct access to the stimulus. Our results provide the first experimental evidence that social learning can contribute to the spread of cannibalistic behaviour in domestic fowl. We suggest that stimulus enhancement and observational conditioning were the social-learning mechanisms involved. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.
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Ward, C., Trisko, R., & Smuts, B. B. (2009). Third-party interventions in dyadic play between littermates of domestic dogs, Canis lupus familiaris. Anim. Behav., 78(5), 1153–1160.
Abstract: Interventions occur when animals interfere in competitive interactions between two or more individuals. Interveners can alter the nature of the ongoing interaction by targeting one party (attacking, biting) and supporting the other. Three theories have been proposed to account for intervention behaviour: kin selection, reciprocity and direct benefits. The kin selection hypothesis predicts that interveners will selectively support relatives over nonrelatives; the reciprocity hypothesis predicts that when intervener [`]A' supports individual [`]B', later [`]B' will intervene and support [`]A'; and the direct benefits hypothesis predicts that target/support patterns should serve the immediate interests of the intervener. We tested the reciprocity and direct benefits hypotheses by exploring third-party interventions in play fighting among littermates of domestic dogs. Interveners in dyadic play did not preferentially target or support preferred playmates of the intervener. Interveners targeted the dog in the losing role at the time of the intervention, and they did not show reciprocity in support. Taken together, these last two findings suggest that littermates benefit directly and use interventions opportunistically to practise offence behaviours directed at littermates already behaving subordinately. Opportunities to practise targeting in a playful setting may help structure dominance relationships among littermates. Additionally, the tendency for puppies to do what the other is doing (target the dog in the losing role) may pave the way for synchronizing cooperative behaviours during group hunting and territorial defence. The types of behaviours used to intervene changed over development, but the outcome following an intervention remained stable.
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Ziegler, W. H. (1976). [Endocrinological studies in arterial hypertension. Search for phaeochromocytoma]. Schweiz Med Wochenschr, 106(34), 1148–1150.
Abstract: Elevated urinary catecholamines and their metabolites are the only findings which confirm the presence of pheochromocytoma. This examination is of particular interest if carried out in urine produced after spontaneous hypertensive episodes. Pharmacologic tests when carried out under standard conditions have proven to be a reliable aid in cases of suspected pheochromocytoma. Roentgenographic studies, determination of local plasma catecholamine concentrations and blood volume control should be undertaken in these patients before surgical procedure.
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Llusia, D., Márquez, R., & Beltrán, J. F. (2010). Non-Selective and Time-Dependent Behavioural Responses of Common Toads (Bufo bufo) to Predator Acoustic Cues. Ethology, 116(12), 1146–1154.
Abstract: Abstract Acoustic predator recognition has rarely been studied in anurans, in spite of the fact that hearing is widespread in these animals and that it has been demonstrated to play an important role in both arthropods and other vertebrates. Using field playback experiments, we tested the hypothesis that adult common toads (Bufo bufo) are capable of recognizing natural vocalizations of a common predator, the Eurasian otter (Lutra lutra), and show antipredator responses. We found that toads exposed to both natural (two types of otter sounds) and synthetic stimuli [white noise (WN) and otter sound-based amplitude modulated WN] increased time allocated to locomotion and escape behaviour. These responses were correlated with time elapsed from sunset to the onset of testing and were independent from the type of acoustic signal, toad features and other environmental factors monitored. We conclude that B. bufo has not developed a selective recognition of predator vocalizations, suggesting that low-frequency or seismic sounds associated with predator movements may provide anurans with better cues about an approaching risk. We propose that the time-dependent response to acoustic stimuli of common toads represents a case of threat-sensitivity and demonstrates that it can occur even when the response to the threat is not predator specific.
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Sara J. Shettleworth. (1999). Female mate choice in swordtails and mollies: symmetry assessment or Weber's law? Anim. Behav., 58(5), 1139–1142.
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Earley, R. L., Druen, M., & Alan Dugatkin, L. (2005). Watching fights does not alter a bystander's response towards naive conspecifics in male green swordtail fish, Xiphophorus helleri. Anim. Behav., 69(5), 1139–1145.
Abstract: Bystanders are capable of extracting cues from signalling interactions between others and appear to use information gained via eavesdropping when confronted with the watched individuals. A question that has gained little attention is whether observing fights affects bystander behaviour outside the context of interacting with the watched individuals. Our aim was to determine whether watching fights elicits general changes in bystander aggression levels in Xiphophorus helleri. We manipulated the bystanders' ability to witness encounters using clear, one-way-mirror and opaque partitions. After watching (or not watching) an initial contest, the bystanders were pitted against naive conspecifics instead of the animals they had seen fight. Observing fights did not alter the bystanders' propensity to initiate aggression, escalate, or win against naive individuals, indicating that bystanders do not experience general changes in aggressive behaviour after watching a fight. Earlier work in this species, however, has shown that bystanders respond in predictable ways to individuals they have witnessed winning or losing a fight. Taken together, these data support the notion that bystanders consistently modify their behaviour towards previously watched winners or losers in response to information gained via eavesdropping. We discuss our results in light of some recent work on the behavioural and endocrinological responses triggered by watching fights and suggest that comparative approaches to understanding networking phenomena may be productive.
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