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Author Uzawa, T.; Akiyama, S.; Kimura, T.; Takahashi, S.; Ishimori, K.; Morishima, I.; Fujisawa, T. doi  openurl
  Title Collapse and search dynamics of apomyoglobin folding revealed by submillisecond observations of alpha-helical content and compactness Type Journal Article
  Year 2004 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 101 Issue 5 Pages 1171-1176  
  Keywords Animals; Apoproteins/*chemistry; Circular Dichroism; Cytochromes c/chemistry; Horses; Myoglobin/*chemistry; *Protein Folding; *Protein Structure, Secondary; Scattering, Radiation  
  Abstract The characterization of protein folding dynamics in terms of secondary and tertiary structures is important in elucidating the features of intraprotein interactions that lead to specific folded structures. Apomyoglobin (apoMb), possessing seven helices termed A-E, G, and H in the native state, has a folding intermediate composed of the A, G, and H helices, whose formation in the submillisecond time domain has not been clearly characterized. In this study, we used a rapid-mixing device combined with circular dichroism and small-angle x-ray scattering to observe the submillisecond folding dynamics of apoMb in terms of helical content (f(H)) and radius of gyration (R(g)), respectively. The folding of apoMb from the acid-unfolded state at pH 2.2 was initiated by a pH jump to 6.0. A significant collapse, corresponding to approximately 50% of the overall change in R(g) from the unfolded to native conformation, was observed within 300 micros after the pH jump. The collapsed intermediate has a f(H) of 33% and a globular shape that involves >80% of all its atoms. Subsequently, a stepwise helix formation was detected, which was interpreted to be associated with a conformational search for the correct tertiary contacts. The characterized folding dynamics of apoMb indicates the importance of the initial collapse event, which is suggested to facilitate the subsequent conformational search and the helix formation leading to the native structure.  
  Address Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510, Japan  
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  ISSN 0027-8424 ISBN Medium  
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  Notes PMID:14711991 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3779  
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Author Mettke-Hofmann, C.; Gwinner, E. doi  openurl
  Title Long-term memory for a life on the move Type Journal Article
  Year 2003 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 100 Issue 10 Pages 5863-5866  
  Keywords Animals; Germany; Israel; Memory/*physiology; Models, Biological; Periodicity; Songbirds/*physiology  
  Abstract Evidence is accumulating that cognitive abilities are shaped by the specific ecological conditions to which animals are exposed. Long-distance migratory birds may provide a striking example of this. Field observations have shown that, at least in some species, a substantial proportion of individuals return to the same breeding, wintering, and stopover sites in successive years. This observation suggests that migrants have evolved special cognitive abilities that enable them to accomplish these feats. Here we show that memory of a particular feeding site persisted for at least 12 months in a long-distance migrant, whereas a closely related nonmigrant could remember such a site for only 2 weeks. Thus, it seems that the migratory lifestyle has influenced the learning and memorizing capacities of migratory birds. These results build a bridge between field observations suggesting special memorization feats of migratory birds and previous neuroanatomical results from the same two species indicating an increase in relative hippocampal size from the first to the second year of life in the migrant but not in the nonmigrant.  
  Address Max Planck Research Centre for Ornithology, Department of Biological Rhythms and Behaviour, Von-der-Tann-Strasse 7, 82346 Andechs, Germany. mettke-hofmann@erl.ornithol.mpg.de  
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  ISSN 0027-8424 ISBN Medium  
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  Notes PMID:12719527 Approved no  
  Call Number refbase @ user @ Serial 511  
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Author Chase, I.D.; Tovey, C.; Spangler-Martin, D.; Manfredonia, M. doi  openurl
  Title Individual differences versus social dynamics in the formation of animal dominance hierarchies Type Journal Article
  Year 2002 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 99 Issue 8 Pages 5744-5749  
  Keywords Animals; *Behavior, Animal; Fishes; Humans; *Social Behavior; *Social Dominance  
  Abstract Linear hierarchies, the classical pecking-order structures, are formed readily in both nature and the laboratory in a great range of species including humans. However, the probability of getting linear structures by chance alone is quite low. In this paper we investigate the two hypotheses that are proposed most often to explain linear hierarchies: they are predetermined by differences in the attributes of animals, or they are produced by the dynamics of social interaction, i.e., they are self-organizing. We evaluate these hypotheses using cichlid fish as model animals, and although differences in attributes play a significant part, we find that social interaction is necessary for high proportions of groups with linear hierarchies. Our results suggest that dominance hierarchy formation is a much richer and more complex phenomenon than previously thought, and we explore the implications of these results for evolutionary biology, the social sciences, and the use of animal models in understanding human social organization.  
  Address Department of Sociology, State University of New York, Stony Brook, NY 11794-4356, USA. Ichase@notes.cc.sunysb.edu  
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  Notes PMID:11960030 Approved no  
  Call Number refbase @ user @ Serial 442  
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Author Seyfarth, R.M.; Cheney, D.L. doi  openurl
  Title What are big brains for? Type Journal Article
  Year 2002 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 99 Issue 7 Pages 4141-4142  
  Keywords Animals; Brain/*anatomy & histology; *Intelligence; Learning; Primates/*anatomy & histology/*psychology; Social Behavior  
  Abstract  
  Address Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA. seyfarth@psych.upenn.edu  
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  Notes PMID:11929989 Approved no  
  Call Number refbase @ user @ Serial 692  
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Author Jansen, T.; Forster, P.; Levine, M.A.; Oelke, H.; Hurles, M.; Renfrew, C.; Weber, J.; Olek, K. doi  openurl
  Title Mitochondrial DNA and the origins of the domestic horse Type Journal Article
  Year 2002 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 99 Issue 16 Pages 10905-10910  
  Keywords Animals; Animals, Domestic/classification/*genetics; Base Sequence; DNA, Complementary; *DNA, Mitochondrial; *Evolution, Molecular; Horses/classification/*genetics; Molecular Sequence Data; Phylogeny  
  Abstract The place and date of the domestication of the horse has long been a matter for debate among archaeologists. To determine whether horses were domesticated from one or several ancestral horse populations, we sequenced the mitochondrial D-loop for 318 horses from 25 oriental and European breeds, including American mustangs. Adding these sequences to previously published data, the total comes to 652, the largest currently available database. From these sequences, a phylogenetic network was constructed that showed that most of the 93 different mitochondrial (mt)DNA types grouped into 17 distinct phylogenetic clusters. Several of the clusters correspond to breeds and/or geographic areas, notably cluster A2, which is specific to Przewalski's horses, cluster C1, which is distinctive for northern European ponies, and cluster D1, which is well represented in Iberian and northwest African breeds. A consideration of the horse mtDNA mutation rate together with the archaeological timeframe for domestication requires at least 77 successfully breeding mares recruited from the wild. The extensive genetic diversity of these 77 ancestral mares leads us to conclude that several distinct horse populations were involved in the domestication of the horse.  
  Address Biopsytec Analytik GmbH, Marie-Curie-Strasse 1, 53359 Rheinbach, Germany. jansen@biopsytec.com  
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  Notes PMID:12130666 Approved no  
  Call Number refbase @ user @ Serial 772  
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Author Reader, S.M.; Laland, K.N. doi  openurl
  Title Social intelligence, innovation, and enhanced brain size in primates Type Journal Article
  Year 2002 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 99 Issue 7 Pages 4436-4441  
  Keywords Animals; Brain/*anatomy & histology; Evolution; *Intelligence; Learning; Primates/*anatomy & histology/*psychology; Social Behavior  
  Abstract Despite considerable current interest in the evolution of intelligence, the intuitively appealing notion that brain volume and “intelligence” are linked remains untested. Here, we use ecologically relevant measures of cognitive ability, the reported incidence of behavioral innovation, social learning, and tool use, to show that brain size and cognitive capacity are indeed correlated. A comparative analysis of 533 instances of innovation, 445 observations of social learning, and 607 episodes of tool use established that social learning, innovation, and tool use frequencies are positively correlated with species' relative and absolute “executive” brain volumes, after controlling for phylogeny and research effort. Moreover, innovation and social learning frequencies covary across species, in conflict with the view that there is an evolutionary tradeoff between reliance on individual experience and social cues. These findings provide an empirical link between behavioral innovation, social learning capacities, and brain size in mammals. The ability to learn from others, invent new behaviors, and use tools may have played pivotal roles in primate brain evolution.  
  Address Department of Zoology, University of Cambridge, High Street, Madingley, Cambridge CB3 8AA, United Kingdom  
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  Notes PMID:11891325 Approved no  
  Call Number Serial 2149  
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Author Johnstone, R.A. doi  openurl
  Title Eavesdropping and animal conflict Type Journal Article
  Year 2001 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 98 Issue 16 Pages 9177-9180  
  Keywords *Aggression; Animals; *Behavior, Animal; *Conflict (Psychology); Models, Theoretical  
  Abstract Fights between pairs of animals frequently take place within a wider social context. The displays exchanged during conflict, and the outcome of an encounter, are often detectable by individuals who are not immediately involved. In at least some species, such bystanders are known to eavesdrop on contests between others, and to modify their behavior toward the contestants in response to the observed interaction. Here, I extend Maynard Smith's well known model of animal aggression, the Hawk-Dove game, to incorporate the possibility of eavesdroppers. I show that some eavesdropping is favored whenever the cost of losing an escalated fight exceeds the value of the contested resource, and that its equilibrium frequency is greatest when costs are relatively high. Eavesdropping reduces the risk of escalated conflict relative to that expected by chance, given the level of aggression in the population. However, it also promotes increased aggression, because it enhances the value of victory. The net result is that escalated conflicts are predicted to occur more frequently when eavesdropping is possible.  
  Address Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, United Kingdom. raj1003@hermes.cam.ac.uk  
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  Notes PMID:11459936 Approved no  
  Call Number refbase @ user @ Serial 497  
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Author Reiss, D.; Marino, L. doi  openurl
  Title Mirror self-recognition in the bottlenose dolphin: a case of cognitive convergence Type Journal Article
  Year 2001 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 98 Issue 10 Pages 5937-5942  
  Keywords Animals; *Cognition; Dolphins/*physiology; *Visual Perception  
  Abstract The ability to recognize oneself in a mirror is an exceedingly rare capacity in the animal kingdom. To date, only humans and great apes have shown convincing evidence of mirror self-recognition. Two dolphins were exposed to reflective surfaces, and both demonstrated responses consistent with the use of the mirror to investigate marked parts of the body. This ability to use a mirror to inspect parts of the body is a striking example of evolutionary convergence with great apes and humans.  
  Address Osborn Laboratories of Marine Sciences, New York Aquarium, Wildlife Conservation Society, Brooklyn, NY 11224, USA. dlr28@columbia.edu  
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  Notes PMID:11331768 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2822  
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Author Griffin, D.R. doi  openurl
  Title Animals know more than we used to think Type
  Year 2001 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 98 Issue 9 Pages 4833-4834  
  Keywords Animal Communication; Animals; Attention/physiology; Brain/physiology; Choice Behavior/physiology; Cognition/*physiology; Humans; Macaca mulatta/physiology/*psychology; Memory/*physiology; Optic Disk/physiology; Psychological Tests  
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  Notes PMID:11320232 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2823  
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Author Hampton, R.R. doi  openurl
  Title Rhesus monkeys know when they remember Type Journal Article
  Year 2001 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume (down) 98 Issue 9 Pages 5359-5362  
  Keywords Animals; Choice Behavior/physiology; Cognition/*physiology; Cues; Food Preferences/psychology; Macaca mulatta/*physiology/*psychology; Male; Memory/*physiology; Probability; Psychological Tests; Reproducibility of Results; Sensitivity and Specificity  
  Abstract Humans are consciously aware of some memories and can make verbal reports about these memories. Other memories cannot be brought to consciousness, even though they influence behavior. This conspicuous difference in access to memories is central in taxonomies of human memory systems but has been difficult to document in animal studies, suggesting that some forms of memory may be unique to humans. Here I show that rhesus macaque monkeys can report the presence or absence of memory. Although it is probably impossible to document subjective, conscious properties of memory in nonverbal animals, this result objectively demonstrates an important functional parallel with human conscious memory. Animals able to discern the presence and absence of memory should improve accuracy if allowed to decline memory tests when they have forgotten, and should decline tests most frequently when memory is attenuated experimentally. One of two monkeys examined unequivocally met these criteria under all test conditions, whereas the second monkey met them in all but one case. Probe tests were used to rule out “cueing” by a wide variety of environmental and behavioral stimuli, leaving detection of the absence of memory per se as the most likely mechanism underlying the monkeys' abilities to selectively decline memory tests when they had forgotten.  
  Address Section on the Neurobiology of Learning and Memory, Laboratory of Neuropsychology, National Institute of Mental Health, Building 49, Room 1B-80, Bethesda, MD 20892, USA. robert@ln.nimh.nih.gov  
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  ISSN 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11274360 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2824  
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