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Fairhurst, S., Gallistel, C. R., & Gibbon, J. (2003). Temporal landmarks: proximity prevails. Anim. Cogn., 6(2), 113–120.
Abstract: Subjects in conditioning experiments time their conditioned responses relative to the onsets of the conditioned stimuli (CSs). These onsets are temporal landmarks, by reference to which subjects may estimate the location of the unconditioned stimulus (US) in time. In a serial compound conditioning paradigm, a long duration CS comes on first, followed later by a second shorter CS, creating both a long-range and a short-range predictor of the US. We ask whether displacing the short-range predictor relative to the long-range predictor causes subjects to strike a compromise between the different temporal locations predicted by the two CSs. In three experiments with pigeons, we varied the training conditions so as to favor or militate against this outcome. However, in all conditions, there was no compromise; after the onset of the displaced short-range CS, the timing of conditioned responding was governed by it alone. This result contrasts with the compromises that are seen when the feeding time predicted by a CS is put in conflict with the time predicted by the circadian clock, and with the similar compromises sometimes seen when a nearby spatial landmark is displaced relative to a larger spatial context.
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Uller, C., Jaeger, R., Guidry, G., & Martin, C. (2003). Salamanders ( Plethodon cinereus) go for more: rudiments of number in an amphibian. Anim. Cogn., 6(2), 105–112.
Abstract: Techniques traditionally used in developmental research with infants have been widely used with nonhuman primates in the investigation of comparative cognitive abilities. Recently, researchers have shown that human infants and monkeys select the larger of two numerosities in a spontaneous forced-choice discrimination task. Here we adopt the same method to assess in a series of experiments spontaneous choice of the larger of two numerosities in a species of amphibian, red-backed salamanders ( Plethodon cinereus). The findings indicate that salamanders “go for more,” just like human babies and monkeys. This rudimentary capacity is a type of numerical discrimination that is spontaneously present in this amphibian.
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Neiworth, J. J., Steinmark, E., Basile, B. M., Wonders, R., Steely, F., & DeHart, C. (2003). A test of object permanence in a new-world monkey species, cotton top tamarins (Saguinus oedipus). Anim. Cogn., 6(1), 27–37.
Abstract: Cotton top tamarins were tested in visible and invisible displacement tasks in a method similar to that used elsewhere to test squirrel monkeys and orangutans. All subjects performed at levels significantly above chance on visible ( n=8) and invisible ( n=7) displacements, wherein the tasks included tests of the perseverance error, tests of memory in double and triple displacements, and “catch” trials that tested for the use of the experimenter's hand as a cue for the correct cup. Performance on all nine tasks was significantly higher than chance level selection of cups, and tasks using visible displacements generated more accurate performance than tasks using invisible displacements. Performance was not accounted for by a practice effect based on exposure to successive tasks. Results suggest that tamarins possess stage 6 object permanence capabilities, and that in a situation involving brief exposure to tasks and foraging opportunities, tracking objects' movements and responding more flexibly are abilities expressed readily by the tamarins.
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De Stoppelaire, G. H., Gillespie, T. W., Brock, J. C., & Tobin, G. A. (2004). Use of remote sensing techniques to determine the effects of grazing on vegetation cover and dune elevation at Assateague Island National Seashore: impact of horses. Environ Manage, 34(5), 642–649.
Abstract: The effects of grazing by feral horses on vegetation and dune topography at Assateague Island National Seashore were investigated using color-infrared imagery, lidar surveys, and field measurements. Five pairs of fenced and unfenced plots (300 m2) established in 1993 on sand flats and small dunes with similar elevation, topography, and vegetation cover were used for this study. Color-infrared imagery from 1998 and field measurements from 2001 indicated that there was a significant difference in vegetation cover between the fenced and unfenced plot-pairs over the study period. Fenced plots contained a higher percentage of vegetation cover that was dominated by American beachgrass (Ammophila breviligulata). Lidar surveys from 1997, 1999, and 2000 showed that there were significant differences in elevation and topography between fenced and unfenced plot-pairs. Fenced plots were, on average, 0.63 m higher than unfenced plots, whereas unfenced plots had generally decreased in elevation after establishment in 1993. Results demonstrate that feral horse grazing has had a significant impact on dune formation and has contributed to the erosion of dunes at Assateague Island. The findings suggest that unless the size of the feral horse population is reduced, grazing will continue to foster unnaturally high rates of dune erosion into the future. In order to maintain the natural processes that historically occurred on barrier islands, much larger fenced exclosures would be required to prevent horse grazing.
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Cilnis, M. J., Kang, W., & Weaver, S. C. (1996). Genetic conservation of Highlands J viruses. Virology, 218(2), 343–351.
Abstract: We studied molecular evolution of the mosquito-borne alphavirus Highlands J (HJ) virus by sequencing PCR products generated from 19 strains isolated between 1952 and 1994. Sequences of 1200 nucleotides including portions of the E1 gene and the 3' untranslated region revealed a relatively slow evolutionary rate estimated at 0.9-1.6 x 10(-4) substitutions per nucleotide per year. Phylogenetic trees indicated that all HJ viruses descended from a common ancestor and suggested the presence of one dominant lineage in North America. However, two or more minor lineages probably circulated simultaneously for periods of years to a few decades. Strains isolated from a horse suffering encephalitis, and implicated in a recent turkey outbreak, were not phylogenetically distinct from strains isolated in other locations during the same time periods. Our findings are remarkably similar to those we obtained previously for another North American alphavirus, eastern equine encephalomyelitis virus, with which Highlands J shares primary mosquito and avian hosts, geographical distribution, and ecology. These results support the hypotheses that the duration of the transmission season affects arboviral evolutionary rates and vertebrate host mobility influences genetic diversity.
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Connor, R. J., Kawaoka, Y., Webster, R. G., & Paulson, J. C. (1994). Receptor specificity in human, avian, and equine H2 and H3 influenza virus isolates. Virology, 205(1), 17–23.
Abstract: The receptor specificity of 56 H2 and H3 influenza virus isolates from various animal species has been determined to test the relevance of receptor specificity to the ecology of influenza virus. The results show that the receptor specificity of both H2 and H3 isolates evaluated for sialic acid linkage specificity and inhibition of hemagglutination by horse serum correlates with the species of origin, as postulated earlier for H3 strains based on a limited survey of five human, three avian, and one equine strain. Elucidation of the amino acid sequence of several human H2 receptor variants and analysis of known sequences of H2 and H3 isolates revealed that receptor specificity varies in association with an amino acid change at residues 228 in addition to the change at residue 226 previously documented to affect receptor specificity of H3 but not H1 isolates. Residues 226 and 228 are leucine and serine in human isolates, which preferentially bind sialic acid alpha 2,6-galactose beta 1,4-N-acetyl glucosamine (SA alpha 2,6Gal), and glutamine and glycine in avian and equine isolates, which exhibit specificity for sialic acid alpha-2,3-galactose beta-1,3-N-acetyl galactosamine (SA alpha 2,3Gal). The results demonstrate that the correlation of receptor specificity and species of origin is maintained across both H2 and H3 influenza virus serotypes and provide compelling evidence that influenza virus hosts exert selective pressure to maintain the receptor specificity characteristics of strains isolated from that species.
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Cooper, M. A., Berntein, I. S., & Hemelrijk, C. K. (2005). Reconciliation and relationship quality in Assamese macaques (Macaca assamensis). Am. J. Primatol., 65(3), 269–282.
Abstract: A consistent conclusion in reconciliation research is that animals that reconcile are likely to have strong social bonds. This has led to the hypothesis that reconciliation occurs most often between valuable social partners. We tested this hypothesis in a group of Assamese macaques (Macaca assamensis) living near a temple in Assam, India. Using focal sample and ad libitum data collection, we recorded the occurrence of reconciliation, grooming, and agonistic aiding, and the outcomes of approach. We used matrix association methods (TauKr correlation) to correlate reconciliation with grooming, aiding, and approach outcome. Females reconciled more often with females with which they had stronger grooming and aiding relationships. The correlation between reconciliation and aiding was significant for support to the aggressor and the victim. In contrast, no such correlations with reconciliation were found for males. This study provides evidence that females reconcile most often with valuable and compatible social partners. The results do not support the relationship-quality hypothesis for males, and we suggest that future studies give more consideration to the possibility that males reconcile for reasons other than to repair relationships with valuable partners.
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Heath-Lange, S., Ha, J. C., & Sackett, G. P. (1999). Behavioral measurement of temperament in male nursery-raised infant macaques and baboons. Am. J. Primatol., 47(1), 43–50.
Abstract: We define temperament as an individual's set of characteristic behavioral responses to novel or challenging stimuli. This study adapted a temperament scale used with rhesus macaques by Schneider and colleagues [American Journal of Primatology 25:137-155, 1991] for use with male pigtailed macaque (Macaca nemestrina, n = 7), longtailed macaque (M. fascicularis, n = 3), and baboon infants (Papio cynocephalus anubis, n = 4). Subjects were evaluated twice weekly for the first 5 months of age during routine removal from their cages for weighing. Behavioral measures were based on the subject's interactions with a familiar human caretaker and included predominant state before capture, response to capture, contact latency, resistance to tester's hold, degree of clinging, attention to environment, defecation/urination, consolability, facial expression, vocalizations, and irritability. Species differences indicated that baboons were more active than macaques in establishing or terminating contact with the tester. Temperament scores decreased over time for the variables Response to Capture and Contact Latency, indicating that as they grew older, subjects became less reactive and more bold in their interactions with the tester. Temperament scores changed slowly with age, with greater change occurring at younger ages. The retention of variability in reactivity between and within species may be advantageous for primates, reflecting the flexibility necessary to survive in a changing environment.
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Vollmerhaus, B., Roos, H., Gerhards, H., & Knospe, C. (2003). [Phylogeny, form and function of canine teeth in the horse]. Anat Histol Embryol, 32(4), 212–217.
Abstract: The canine teeth of the horse developed phylogenically from the simple, pointed, short-rooted tooth form of the leaf eating, in pairs living, Eocene horse Hyracotherium and served up to the Oligocene as a means of defense (self preservation). In the Miocene the living conditions of the Merychippus changed and they took to eating grass and adopted as a new behavior the life in a herd. The canine teeth possibly played an important role in fights for social ranking; they changed from a crown form to knife-like shape. In the Pliohippus the canine tooth usually remained in male horses and since the Pliocene, it contributed to the fights between stallions, to ensure that the offspring only came from the strongest animals (preservation of the species). Form and construction of the canine tooth are described and discussed in detail under the above mentioned phylogenic and ethologic aspects.
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Wilkins, L. J., Brown, S. N., Zimmerman, P. H., Leeb, C., & Nicol, C. J. (2004). Investigation of palpation as a method for determining the prevalence of keel and furculum damage in laying hens. Vet. Rec., 155(18), 547–549.
Abstract: Old breaks of the keel and furculum were identified by palpation in 500 end-of-lay hens from 10 flocks housed in free-range and barn systems, and the results were compared with the results obtained by a full dissection and inspection. The method was considered to be sufficiently precise to be used as a diagnostic tool although people using it would need to be trained. The results obtained by dissection indicated that 50 to 78 per cent of the birds in the flocks had breaks of the furculum and keel, but no other breaks of bones were detected.
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