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Waring, G. H. (2003). |
Rands, S. A., Cowlishaw, G., Pettifor, R. A., Rowcliffe, J. M., & Johnstone, R. A. (2003). Spontaneous emergence of leaders and followers in foraging pairs. Nature, 423(6938), 432–434.
Abstract: Animals that forage socially often stand to gain from coordination of their behaviour. Yet it is not known how group members reach a consensus on the timing of foraging bouts. Here we demonstrate a simple process by which this may occur. We develop a state-dependent, dynamic game model of foraging by a pair of animals, in which each individual chooses between resting or foraging during a series of consecutive periods, so as to maximize its own individual chances of survival. We find that, if there is an advantage to foraging together, the equilibrium behaviour of both individuals becomes highly synchronized. As a result of this synchronization, differences in the energetic reserves of the two players spontaneously develop, leading them to adopt different behavioural roles. The individual with lower reserves emerges as the 'pace-maker' who determines when the pair should forage, providing a straightforward resolution to the problem of group coordination. Moreover, the strategy that gives rise to this behaviour can be implemented by a simple 'rule of thumb' that requires no detailed knowledge of the state of other individuals.
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Klein, E. D., & Zentall, T. R. (2003). Imitation and affordance learning by pigeons (Columba livia). J Comp Psychol, 117(4), 414–419.
Abstract: The bidirectional control procedure was used to determine whether pigeons (Columba livia) would imitate a demonstrator that pushed a sliding screen for food. One group of observers saw a trained demonstrator push a sliding screen door with its beak (imitation group), whereas 2 other groups watched the screen move independently (possibly learning how the environment works) with a conspecific either present (affordance learning with social facilitation) or absent (affordance learning alone). A 4th group could not see the screen being pushed (sound and odor control). Imitation was evidenced by the finding that pigeons that saw a demonstrator push the screen made a higher proportion of matching screen pushes than observers in 2 appropriate control conditions. Further, observers that watched a screen move without a demonstrator present made a significantly higher proportion of matching screen pushes than would be expected by chance. Thus, these pigeons were capable of affordance learning.
Keywords: Animals; *Behavior, Animal; Columbidae; Cues; *Imitative Behavior; *Learning; Odors; Sound
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Altmann, S. A., & Altmann, J. (2003). The transformation of behaviour field studies. Anim. Behav., 65(3), 413–423.
Abstract: As areas of science mature, they pass through three, broadly overlapping stages of development, characterized respectively by description, explanation and synthesis. Field research on animal behaviour is making the transition from an area with a preponderance of purely descriptive studies to one that also includes the development and testing of verifiable hypotheses about the structure, causes and consequences of behaviour. We survey several reasons for this transformation of behaviour field studies and some of the major trends that characterize it, including: (1) patterns discerned in our cumulative knowledge of natural history; (2) increased support for behaviour field studies; (3) interfaces with related areas of science; (4) the development of observational sampling methods and other aspects of data sampling and analysis; (5) the development of models of behaviour's adaptive functions and life-history consequences; (6) long-term field sites that make possible complete life histories, increased attention to individual differences and intergenerational studies of behaviour; and (7) the development of techniques for remote tracking of animals and for noninvasive, hands-off sampling of a range of behavioural, physiological, genetic and environmental phenomena. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour.
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Westerduin, F. E., Lankveld, D. P. K., van der Velden, M. A., Back, W., & Sloet van Oldruitenborgh-Oosterbaan, M. M. (2003). [Splenectomy in a dressage pony: end of sports career?]. Tijdschr Diergeneeskd, 128(13), 406–411.
Abstract: A 14-year-old Arabian cross-bred gelding was referred to the University Clinic because of mild, recurrent signs of colic for 5 days. The pony showed icteric mucous membranes, haemolytic blood, and dark coloured urine. Internal examination did not give a clear diagnosis. Unidentified intra-abdominal strands were found and haemorrhagic abdominocentesis led to the decision to perform an exploratory laparatomy. An extremely enlarged spleen was the sole finding. A splenal biopsy sample was taken and surgery was completed. The pony remained colicky, so the spleen was examined by ultrasonography. After this examination, the tentative diagnosis 'tumour of the spleen' was made and splenectomy was performed. Pathological examination of the spleen revealed splenomegaly caused by infarctions of unknown origin. Eight weeks after surgery, the pony started again in dressage competition. Six months after splenectomy, the pony won the provincial dressage competition.
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Matsushima, T., Izawa, E. - I., Aoki, N., & Yanagihara, S. (2003). The mind through chick eyes: memory, cognition and anticipation. Zoolog Sci, 20(4), 395–408.
Abstract: To understand the animal mind, we have to reconstruct how animals recognize the external world through their own eyes. For the reconstruction to be realistic, explanations must be made both in their proximate causes (brain mechanisms) as well as ultimate causes (evolutionary backgrounds). Here, we review recent advances in the behavioral, psychological, and system-neuroscience studies accomplished using the domestic chick as subjects. Diverse behavioral paradigms are compared (such as filial imprinting, sexual imprinting, one-trial passive avoidance learning, and reinforcement operant conditioning) in their behavioral characterizations (development, sensory and motor aspects of functions, fitness gains) and relevant brain mechanisms. We will stress that common brain regions are shared by these distinct paradigms, particularly those in the ventral telencephalic structures such as AIv (in the archistriatum) and LPO (in the medial striatum). Neuronal ensembles in these regions could code the chick's anticipation for forthcoming events, particularly the quality/quantity and the temporal proximity of rewards. Without the internal representation of the anticipated proximity in LPO, behavioral tolerance will be lost, and the chick makes impulsive choice for a less optimized option. Functional roles of these regions proved compatible with their anatomical counterparts in the mammalian brain, thus suggesting that the neural systems linking between the memorized past and the anticipated future have remained highly conservative through the evolution of the amniotic vertebrates during the last 300 million years. With the conservative nature in mind, research efforts should be oriented toward a unifying theory, which could explain behavioral deviations from optimized foraging, such as “naive curiosity,” “contra-freeloading,” “Concorde fallacy,” and “altruism.”
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Zentall, T. R., Clement, T. S., & Weaver, J. E. (2003). Symmetry training in pigeons can produce functional equivalences. Psychon Bull Rev, 10(2), 387–391.
Abstract: Functional stimulus equivalence has been demonstrated using a transfer of training design with matching-to-sample training in which two sample stimuli are associated with the same comparison stimulus (A-B, C-B; many-to-one matching). Equivalence is shown by training a new association (A-D) and demonstrating the presence of an emergent relation (C-D). In the present experiment, we show that symmetry training, in which a bidirectional association is trained between two stimuli (A-B, B-A, using successive stimulus presentations followed by reinforcement), can also produce functional equivalence using a transfer of training design (i.e., train B-C, test A-C). The results suggest that training pigeons in the substitutability of two stimuli may be sufficient to produce functional stimulus equivalence between them. The results also have implications for the development of an emergent transitive relation, because training on A-B and B-C relations results in the emergence of an untrained A-C relation, if B-A training also is provided.
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Miksovska, J., & Larsen, R. W. (2003). Photothermal studies of pH induced unfolding of apomyoglobin. J Protein Chem, 22(4), 387–394.
Abstract: Conformational dynamic and enthalpy changes associated with pH induced unfolding of apomyoglobin were studied using photoacoustic calorimetry and photothermal beam deflection methods. The transition between the native state and the I intermediate was induced by a nanosecond pH jump from o-nitrobenzaldehyde photolysis. Deconvolution of photoacoustic waves indicates two kinetic processes. The fast phase (T < 50 ns) is characterized by a volume expansion of 8.8 ml mol(-1). This process is followed by a volume contraction of about -22 ml mol(-1) (tau approximately 500 ns). Photothermal beam deflection measurements do not reveal any volume changes on the time scale between approximately 100 micros and 5 ms. We associate the volume contraction with structural changes occurring during the transition between the native state and the I intermediate. The lack of any processes on the ms time scale may indicate the absence of structural events involving larger conformational changes of apomyoglobin after the pH jump.
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Broucek, J., Ksac, P., & Uhrincat, M. (2003). The effect of sire line on learning and locomotor behaviour of heifers. Czech J. Anim. Sci, 48, 387–394.
Abstract: ABSTRACT: e aim of this study was to test the effect of sire line on maze learning ability and locomotor behaviour
in open-field tests of heifers, consistency over the time of grid crossing and relationship between the time of traversing the maze and grid crossings in open-field tests, respectively. We analysed the results of ethological tests for 54 Holstein heifers that descended from 7 sires. Maze behaviour was observed at the age of 15 weeks, an open-field test was applied at two age periods, 16 weeks and 18 months. We found out highly significant differences in the time of traversing the maze between heifers of different sire origin (P < 0.01). e number of grid crossings over the five minutes of the open-field test did not differ between the daughters of the age of 16 weeks and 18 months. Repeatability between the number of grid crossings at the age of 16 weeks and 18 months was proved by significant correlation (r = 0.2713*). On the contrary, significant relationships between the times of traversing the maze and locomotor behaviour in the open-field test (r =-0.3739*) were found only when the sequence of observations followed after a week pause (age of 15 and 16 weeks). Keywords: heifers; sire; maze; open-field test; repeatability; learning; locomotor behaviour relationship
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Haidn, B., & Berger, N. (2003). Arbeitszeitbedarf für die Pensionspferdehaltung in landwirt-schaftlichen Betrieben. Tagungsband 6, Vechta 25.-27. März 2003, Tagung: Bau, Technik und Umwelt in der landwirtsch, 386–391. |