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Harris, L. J., Almerigi, J. B., Carbary, T. J., & Fogel, T. G. (2001). Left-side infant holding: A test of the hemispheric arousal -attentional hypothesis. Brain and Cognition, 46(1-2), 159–165.
Abstract: When asked to hold a young infant in their arms, most adults hold on the left side (Harris, 1997). In a prior study, we found the same bias when we asked adults merely to imagine holding an infant in their arms (Harris, Almerigi, & Kirsch, 1999). It has been hypothesized that the left-side bias is the product of right-hemisphere arousal accompanying certain aspects of the act, causing attention to be driven to the contralateral, or left, side of personal space. Left-side holding, whether actual or imagined, thus would be consistent with the direction to which the holder's attention has been endogenously directed. We tested this hypothesis by giving 250 college students the “imagine-holding” task and then, as an independent measure of lateralized hemispheric arousal, a 34-item Chimeric Faces Test (CFT). On the “imagine” test, a significant majority reported a left-side hold, and, on the CFT, left-side holders had a significantly stronger left-hemispace bias than right-side holders, although both left- and right- side holders had left-hemispace CFT biases. The results thus support the attentional-arousal hypothesis but indicate that other factors are contributing as well.
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Povinelli DJ, & Dunphy-Lelii S. (2001). Do chimpanzees seek explanations? Preliminary comparative investigations. Can. J. Exp. Psychol., 55, 185.
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Kimura, R. (2001). Volatile substances in feces, urine and urine-marked feces of feral horses. Can. J. Anim. Sci., 81(3), 411–420.
Abstract: The identity and amount of volatile substances in the feces, urine and feces scent-marked with urine (i.e., feces mixed with urine) of feral horses was determined by acid/steam distillation and gas chromatography-mass spectrometry. The frequency of excretion and scent marking, as evaluated in the breeding and non-breeding seasons, showed clear evidence of seasonal behavioral differences. The concentration of each substance (fatty acids, alcohols, aldehydes, phenols, amines and alkanes) in the feces differed according to maturity, sex and stage in the reproductive process. They had a characteristic chemical fingerprint. Although the levels of tetradecanoic and hexadecanoic acids in the feces of estrous mares were significantly higher than the respective levels in the feces of non-estrous mares, in the case of scent-marked feces by stallions, the levels of them in the feces from estrous mares had decreased to levels similar to those in non-estrous mares. The concentration of these substances in mares were not significantly different. The presence of a high concentration of cresols in the urine of stallions in the breeding season suggests that one role of scent marking by stallions is masking the odor of the feces produced by mares.
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Santos LR, Hauser MD, & Spelke ES. (2001). Recognition and categorization of biologically significant objects by rhesus monkeys (Macaca mulatta): the domain of food. Cognition, 82, 127.
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Mushiake H., Saito N., Sakamoto K., Sato Y., & Tanji J. (2001). Visually based path-planning by Japanese monkeys. Cognitive Brain Research, 11, 165–169.
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Zentall, T. R. (2001). Imitation In Animals: Evidence, Function, And Mechanisms. Cybern Syst, 32, 53–96.
Abstract: The terms sociallearning and social influence have been used descriptively and theoretically to characterize a broad range of animal behavior from physical antipredatory adaptations such as eye spots, which are totally under genetic control, to the human capacity for the exaggeration of individual characteristics, known as caricature, which are largely under cognitive control. In the present review, the various forms of social influence and social learning are identified and distinghished from imitation, a term that generally has been reserved for behavioral matching that cannot be accounted for using simpler specifically predisposed, motivational, or learning mechanisms. It is suggested that much of the ambiguity in the literature concerning the various forms of social learning can be attributed to the distinction between the function of a behavior and the mechanisms responsible for its occurrence. Finally, the various mechanisms that have been proposed to account for imitative learning are presented and an attempt is made to evaluate them.
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Itakura, S., Agnetta, B., Hare, B., & Tomasello, M. (2001). Chimpanzee Use of Human and Conspecific Social Cues to Locate Hidden Food. Dev Sci, 2(2), 448–456.
Abstract: Two studies are reported in which chimpanzees attempted to use social cues to locate hidden food in one of two possible hiding places. In the first study four chimpanzees were exposed to a local enhancement cue (the informant approached and looked to the location where food was hidden and then remained beside it) and a gaze/point cue (the informant gazed and manually pointed towards the location where the food was hidden). Each cue was given by both a human informant and a chimpanzee informant. In the second study 12 chimpanzees were exposed to a gaze direction cue in combination with a vocal cue (the human informant gazed to the hiding location and produced one of two different vocalizations – a 'food-bark' or a human word-form). The results were – (i) all subjects were quite skillful with the local enhancement cue, no matter who produced it; (ii) few subjects were skillful with the gaze/point cue, no matter who produced it (most of these being individuals who had been raised in infancy by humans); and (iii) most subjects were skillful when the human gazed and vocalized at the hiding place, with little difference between the two types of vocal cue. Findings are discussed in terms of chimpanzees' apparent need for additional cues, over and above gaze direction cues, to indicate the presence of food.
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Elsaesser, F., Klobasa, F., & Ellendorff, F. (2001). ACTH stimulation test for the determination of salivary cortisol and of cortisol responses as markers of the training status/fitness of warm-blooded sports horses]. Dtsch Tierarztl Wochenschr, 108(1), 31–36.
Abstract: Previous work (Marc et al., 2000) suggested that plasma cortisol responses to treadmill exercise or ACTH injection are a reliable marker for performance evaluation in warmblood horses. For practical purposes blood sample collections and treadmill exercise tests are somewhat troublesome and time consuming. The goal of this study was thus to evaluate the use of saliva for cortisol determination (by direct EIA) as a marker for performance and to investigate the reliability and repeatability of plasma cortisol responses to a single i.v. injection of ACTH (50 micrograms or 250 micrograms). Furthermore, the effect of training horses for 8 weeks 3 times per week covering the same distance (increasing from 3.5 km during the first week to 8 km during the last week) either by trotting (approximately 240 m/min) or by cantering (375 m/min) was investigated. For this purpose initially ten four-year-old Hannovarian geldings, all reared in the same State stud, were used. Mean overall correlation between salivary cortisol and plasma cortisol concentrations was 0.64 when samples of various points of time were used. However, in spite of attempts to standardize saliva sample collection, correlation between salivary cortisol levels and plasma cortisol levels at distinct points of time in different tests were low and significant (r = 0.85, p < 0.02) only in one test. Thus, salivary cortisol measurements for diagnostic purposes are not reliable or useful. The repeatability of plasma cortisol responses to ACTH for untrained and trained horses were r = 0.86 and r = 0.8 respectively (p < or = 0.01 and p < or = 0.05 respectively). Training horses either by trotting or cantering did not affect the cortisol response either to treadmill exercise or to stimulation by ACTH. It is concluded that the relationship between salivary cortisol levels and plasma cortisol levels is not close enough to allow the use of salivary cortisol determination as marker of the training status/fitness of horses. The repeatability of the cortisol response to ACTH is similar to the cortisol response to treadmill exercise. Based on plasma cortisol responses to ACTH or treadmill exercise training horses by cantering at low speed is not superior to training by trotting for the fitness of horses.
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Marfin, A. A., Petersen, L. R., Eidson, M., Miller, J., Hadler, J., Farello, C., et al. (2001). Widespread West Nile virus activity, eastern United States, 2000. Emerg Infect Dis, 7(4), 730–735.
Abstract: In 1999, the U.S. West Nile (WN) virus epidemic was preceded by widespread reports of avian deaths. In 2000, ArboNET, a cooperative WN virus surveillance system, was implemented to monitor the sentinel epizootic that precedes human infection. This report summarizes 2000 surveillance data, documents widespread virus activity in 2000, and demonstrates the utility of monitoring virus activity in animals to identify human risk for infection.
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Watt, L. M., & McDonnell, S. M. (2001). Demonstration of Concept Formation in the Horse. Philadephia: University of Pennsylvania.
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