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Friedrich, A. M., Clement, T. S., & Zentall, T. R. (2004). Functional equivalence in pigeons involving a four-member class. Behav. Process., 67(3), 395–403.
Abstract: Research suggests that animals are capable of forming functional equivalence relations or stimulus classes of the kind usually demonstrated by humans (e.g., the class defined by an object and the word for that object). In pigeons, such functional equivalences are typically established using many-to-one matching-to-sample in which two samples are associated with one comparison stimulus and two different samples are associated with the other. Evidence for the establishment of functional equivalences between samples associated with the same comparison comes from transfer tests. In Experiment 1, we found that pigeons can form a single class consisting of four members (many-to-one matching) when the alternative class has only one member (one-to-one matching). In Experiment 2, we ruled out the possibility that the pigeons acquired the hybrid one-to-one/many-to-one task by developing a single-code/default coding strategy as earlier research suggested that it might. Thus, pigeons can develop a functional class consisting of as many as four members, with the alternative class consisting of a single member.
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Sands, J., & Creel, S. (2004). Social dominance, aggression and faecal glucocorticoid levels in a wild population of wolves, Canis lupus. Anim. Behav., 67(3), 387–396.
Abstract: Adrenal glucocorticoid (GC) secretion is an important component of the response to stress in vertebrates. A short-term increase in circulating GCs serves to redirect energy from processes that can be briefly curtailed without harm, allowing energy to be directed towards eliminating or avoiding the stressor. In contrast, prolonged elevation of GCs can cause a broad range of pathologies, including reproductive suppression. We examined whether social subordination in wolves leads to chronically elevated GC levels, and whether this [`]social stress' causes reproductive suppression of subordinates in cooperatively breeding species. Behavioural and endocrine data collected over 2 years from three packs of free-living wolves in Yellowstone National Park did not support this hypothesis. GC levels were significantly higher in dominant wolves than in subordinates, for both sexes, in all packs, in both years of study. Unlike other cooperatively breeding carnivores (e.g. dwarf mongooses, Helogale parvula, and African wild dogs, Lycaon pictus), high GCs in dominant wolves were not associated with high rates of aggression or agonistic interaction. Aggression increased for wolves of all ranks during mating periods, accompanied by a significant rise in GC levels. If chronic elevation of GCs carries fitness costs, then social stress in wolves (and many other social species) is a cost of dominance, not a consequence of subordination. The specific behavioural correlates of dominance that affect GC levels appear to vary among species, even those with similar social systems.
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Proudman, C., Pinchbeck, G., Clegg, P., & French, N. (2004). Equine welfare: risk of horses falling in the Grand National. Nature, 428(6981), 385–386.
Abstract: As in other competitive sports, the famous Grand National steeplechase, which is held at Aintree in the United Kingdom and is watched by 600 million people worldwide, sometimes results in injury. By analysing data from the past 15 Grand National races (consisting of 560 starts by horses), we are able to identify several factors that are significantly associated with failure to complete the race: no previous experience of the course and its unique obstacles, unfavourable ground conditions (too soft or too hard), a large number of runners, and the length of the odds ('starting price'). We also find that there is an increased risk of falling at the first fence and at the jump known as Becher's Brook, which has a ditch on the landing side. Our findings indicate ways in which the Grand National could be made safer for horses and illustrate how epidemiological analysis might contribute to preventing injury in competitive sport.
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Pinchbeck, G. L., Clegg, P. D., Proudman, C. J., Morgan, K. L., & French, N. R. (2004). Whip use and race progress are associated with horse falls in hurdle and steeplechase racing in the UK. Equine Vet J, 36(5), 384–389.
Abstract: REASONS FOR PERFORMING STUDY: Falls during racing present a risk of injury to both horse and jockey and a risk of fatality to horses. OBJECTIVES: To use video recordings of races to describe the circumstances surrounding horse falls at hurdle and steeplechase fences and to identify and quantify within-race risk factors for horse falls in National Hunt racing in the UK. METHODS: A retrospective, matched, nested case-control study using video recordings of races was conducted on 6 UK racecourses. Cases and controls were matched on both race type and jump number at which the fall occurred. Conditional logistic regression analysis was used to examine the univariable and multivariable relationship between predictor variables and the risk of falling. RESULTS: The risk of falling was significantly associated with whip use and race progress. Horses which were being whipped and progressing through the race were at greater than 7 times the risk of falling compared to horses which were not being whipped and which had no change in position or lost position through the field. CONCLUSIONS: This study has identified whip use and the position of the horse with respect to others in the field as potential risk factors for horse falls. POTENTIAL RELEVANCE: If these findings are confirmed by the use of intervention trials (e.g. with whip-free or restricted whip use races), modifications could be introduced which would reduce the frequency of horse falls, leading to improved equine welfare.
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Pongrácz, P., Miklósi, Á., Timár-Geng, K., & Csányi, V. (2004). Verbal Attention Getting as a Key Factor in Social Learning Between Dog (Canis familiaris) and Human. J. Comp. Psychol., 118(4), 375–383.
Abstract: Pet dogs (Canis familiaris) learn to detour a V-shaped fence effectively from an unfamiliar human demonstrator. In this article, 4 main features of the demonstrator's behavior are highlighted: (a) the manipulation of the target, (b) the familiarity of the demonstrator, (c) the role of verbal attention-getting behavior, and (d) whether a strange trained dog could also be an effective demonstrator. The results show that the main factor of a successful human demonstration is the continuous verbal communication with the dog during detouring. It was also found that an unfamiliar dog demonstrator was as efficient as the unfamiliar experimenter. The experiments provide evidence that in adult dogs, communicative context with humans is needed for effective interspecific social learning to take place. (PsycINFO Database Record (c) 2010 APA, all rights reserved)
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Guo, G. L., Moffit, J. S., Nicol, C. J., Ward, J. M., Aleksunes, L. A., Slitt, A. L., et al. (2004). Enhanced acetaminophen toxicity by activation of the pregnane X receptor. Toxicol Sci, 82(2), 374–380.
Abstract: The pregnane X receptor (PXR) is a ligand-activated transcription factor and member of the nuclear receptor superfamily. Activation of PXR represents an important mechanism for the induction of cytochrome P450 3A (CYP3A) enzymes that can convert acetaminophen (APAP) to its toxic intermediate metabolite, N-acetyl-p-benzoquinone imine (NAPQI). Therefore, it was hypothesized that activation of PXR plays a major role in APAP-induced hepatotoxicity. Pretreatment with the PXR activator, pregnenolone 16alpha-carbonitrile (PCN), markedly enhanced APAP-induced hepatic injury, as revealed by increased serum ALT levels and hepatic centrilobular necrosis, in wild-type but not in PXR-null mice. Further analysis showed that following PCN treatment, PXR-null mice had lower CYP3A11 expression, decreased NAPQI formation, and increased maintenance of hepatic glutathione content compared to wild-type mice. Thus, these results suggest that PXR plays a critical role in APAP-induced hepatic toxicity, probably by inducing CYP3A11 expression and hence increasing bioactivation.
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Sih, A., Bell, A., & Johnson, J. C. (2004). Behavioral syndromes: an ecological and evolutionary overview. Trends. Ecol. Evol, 19(7), 372–378.
Abstract: Recent studies suggest that populations and species often exhibit behavioral syndromes; that is, suites of correlated behaviors across situations. An example is an aggression syndrome where some individuals are more aggressive, whereas others are less aggressive across a range of situations and contexts. The existence of behavioral syndromes focuses the attention of behavioral ecologists on limited (less than optimal) behavioral plasticity and behavioral carryovers across situations, rather than on optimal plasticity in each isolated situation. Behavioral syndromes can explain behaviors that appear strikingly non-adaptive in an isolated context (e.g. inappropriately high activity when predators are present, or excessive sexual cannibalism). Behavioral syndromes can also help to explain the maintenance of individual variation in behavioral types, a phenomenon that is ubiquitous, but often ignored. Recent studies suggest that the behavioral type of an individual, population or species can have important ecological and evolutionary implications, including major effects on species distributions, on the relative tendencies of species to be invasive or to respond well to environmental change, and on speciation rates. Although most studies of behavioral syndromes to date have focused on a few organisms, mainly in the laboratory, further work on other species, particularly in the field, should yield numerous new insights.
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Gould, J. L. (2004). Animal cognition. Curr Biol, 14(10), R372–5.
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Kanazawa, S. (2004). Social sciences are branches of biology. Socioecon. Rev., 2(3), 371–390.
Abstract: Since biology is the study of living organisms, their behaviour and social systems, and since humans are living organisms, it is possible to suggest that social sciences (the study of human behaviour and social systems) are branches of biology and all social scientific theories should be consistent with known biological principles. To claim otherwise and to establish a separate science only for humans might be analogous to the establishment of hydrogenology, the study of hydrogen separate from and inconsistent with the rest of physics. Evolutionary psychology is the application of evolutionary biology to humans, and provides the most general (panspecific) explanations of human behaviour, cognitions, emotions and human social systems. Evolutionary psychology's recognition that humans are animals can explain some otherwise perplexing empirical puzzles in social sciences, such as why there is a wage penalty for motherhood but a wage reward for fatherhood, and why boys produce a greater wage reward for fathers than do girls. The General Social Survey data illustrate the evolutionary psychological argument that reproductive success is important for both men's and women's happiness, but money is only important for men's.
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De Sousa, R. (2004). Rational Animals. Croatian Journal of Philosophy, 4(12), 365–386.
Abstract: I begin with a rather unpromising dispute that Nozick once had with Ian Hacking in the pages of the London Review of Books, in which both vied with one another in their enthusiasm to repudiate the thesis that some human people or peoples are closer than others to animality. I shall attempt to show that one can build, on the basis of Nozick’s discussion of rationality, a defense of the view that the capacity for language places human rationality out of reach of a comparison with animals. The difference rests, paradoxi–cally, on the human capacity for irrationality. Irrationality depends on the capacity for language, which allows the detachment of explicit thoughts from their underlying dynamic implementation; these, in turn, condition the essential disputability of principles of rationality. That is what places every human potentially—if not actually—on the other side of an unbridge–able gulf that separates us from other animals.
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