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Author Scheffer, M.; van Nes, E.H. doi  openurl
  Title Self-organized similarity, the evolutionary emergence of groups of similar species Type Journal Article
  Year 2006 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume 103 Issue 16 Pages 6230-6235  
  Keywords Animals; *Competitive Behavior; *Ecosystem; *Evolution; *Models, Biological  
  Abstract (up) Ecologists have long been puzzled by the fact that there are so many similar species in nature. Here we show that self-organized clusters of look-a-likes may emerge spontaneously from coevolution of competitors. The explanation is that there are two alternative ways to survive together: being sufficiently different or being sufficiently similar. Using a model based on classical competition theory, we demonstrate a tendency for evolutionary emergence of regularly spaced lumps of similar species along a niche axis. Indeed, such lumpy patterns are commonly observed in size distributions of organisms ranging from algae, zooplankton, and beetles to birds and mammals, and could not be well explained by earlier theory. Our results suggest that these patterns may represent self-constructed niches emerging from competitive interactions. A corollary of our findings is that, whereas in species-poor communities sympatric speciation and invasion of open niches is possible, species-saturated communities may be characterized by convergent evolution and invasion by look-a-likes.  
  Address Aquatic Ecology and Water Quality Management Group, Department of Environmental Sciences, Wageningen University, P.O. Box 8080, 6700 DD, Wageningen, The Netherlands. marten.scheffer@wur.nl  
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  ISSN 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16585519 Approved no  
  Call Number refbase @ user @ Serial 510  
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Author Brosnan, S.F.; Schiff, H.C.; de Waal, F.B.M. doi  openurl
  Title Tolerance for inequity may increase with social closeness in chimpanzees Type Journal Article
  Year 2005 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 272 Issue 1560 Pages 253-258  
  Keywords Analysis of Variance; Animals; *Attitude; Group Processes; Pan troglodytes/*psychology; Reward; *Social Behavior; Socioeconomic Factors  
  Abstract (up) Economic decision-making depends on our social environment. Humans tend to respond differently to inequity in close relationships, yet we know little about the potential for such variation in other species. We examine responses to inequity in several groups of chimpanzees (Pan troglodytes) in a paradigm similar to that used previously in capuchin monkeys (Cebus apella). We demonstrate that, like capuchin monkeys, chimpanzees show a response to inequity of rewards that is based upon the partner receiving the reward rather than the presence of the reward alone. However, we also found a great amount of variation between groups tested, indicating that chimpanzees, like people, respond to inequity in a variable manner, which we speculate could be caused by such variables as group size, the social closeness of the group (as reflected in length of time that the group has been together) and group-specific traditions.  
  Address Yerkes National Primate Research Center, Emory University, 954 North Gatewood Drive, Atlanta, GA 30329, USA. sbrosna@emory.edu  
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  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15705549 Approved no  
  Call Number refbase @ user @ Serial 169  
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Author Pickerel, T.M.; Crowell-Davis, S.L.; Caudle, A.B.; Estep, D.Q. url  openurl
  Title Sexual preference of mares (Equus caballus) for individual stallions Type Journal Article
  Year 1993 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 38 Issue 1 Pages 1-13  
  Keywords Horse; Sexual behavior; Sexual preference; Vocalization  
  Abstract (up) Eight mares were tested to determine if they remained near one of two stallions longer than would be expected if association was random. Six stallions were paired in 30 combinations and each mare was tested 30 times. The mares (Equus caballus) demonstrated a definite preference for individual stallions throughout the breeding season. This preference was influenced by the estrous state of the mare. During estrus, mares' preferences for stallions were positively correlated with the rate at which a given stallion vocalized. During diestrus, mares spent significantly less time in the proximity of stallions and did not exhibit any preference for individual stallions.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 2270  
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Author Sweeting, M.P.; Houpt, C.E.; Houpt, K.A. url  openurl
  Title Social Facilitation of Feeding and Time Budgets in Stabled Ponies Type Journal Article
  Year 1985 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.  
  Volume 60 Issue 2 Pages 369-374  
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  Abstract (up) Eight pairs of pony mares were observed. Members of a pair were housed in adjacent stalls and fed hay ad libitum. The behavior of both ponies was recorded simultaneously in the morning (1000 to 1200 h) and afternoon (1400 to 1600 h) for a total of 117 h. The time budget was: 70.1 {+/-} 8.6% eating; 17.8 {+/-} 7.4% standing (including stand rest, stand alert and stand nonajert); 5.2 {+/-} 7.0% pushing hay; 2.9 {+/-} 1.2% walking; 1.9 {+/-} 2.9% drinking; 1.3 {+/-} 1.1% self-grooming; .2 {+/-} .3% defecating; .06 {+/-} .1% chewing nonfood items; .06 {+/-} .03% urination; .06 {+/-} .1% licking salt; .07 {+/-} .1% pawing hay; .6 {+/-} .7% lying and .07 {+/-} .08% stretching the neck over the stall wall dividing the ponies. While eating, the ponies lifted their heads 25.4 {+/-} 11.0 times/h. In less than one-half of the occasions when urination or defecation was observed, the ponies walked away from the spot where they had been eating to eliminate. During one-half of the observations, visual contact between the ponies was prevented by a solid partition between the stalls. The ponies spent significantly more time standing nonalert when the partition prevented visual contact (12 {+/-} 7%) than when visual contact could take place (6 {+/-} 3%, P<.05). When fresh hay was supplied in the mornings, the ponies spent similar amounts of time eating whether visual contact was allowed or not, but in the afternoon significantly more time was spent feeding when visual contact was allowed (73 {+/-} 4%) than when it was not (60 {+/-} 7%). Less time was spent eating, in the absence of visual contact, despite the presence of auditory and olfactory contact. Apparently social facilitation is important in maintaining feeding behavior in ponies. N1 -  
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  Call Number Equine Behaviour @ team @ Serial 4232  
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Author Blaisdell, A.P.; Sawa, K.; Leising, K.J.; Waldmann, M.R. doi  openurl
  Title Causal reasoning in rats Type Journal Article
  Year 2006 Publication Science (New York, N.Y.) Abbreviated Journal Science  
  Volume 311 Issue 5763 Pages 1020-1022  
  Keywords Animals; *Association Learning; Bayes Theorem; *Cognition; Comprehension; Forecasting; Male; Rats; Rats, Long-Evans  
  Abstract (up) Empirical research with nonhuman primates appears to support the view that causal reasoning is a key cognitive faculty that divides humans from animals. The claim is that animals approximate causal learning using associative processes. The present results cast doubt on that conclusion. Rats made causal inferences in a basic task that taps into core features of causal reasoning without requiring complex physical knowledge. They derived predictions of the outcomes of interventions after passive observational learning of different kinds of causal models. These competencies cannot be explained by current associative theories but are consistent with causal Bayes net theories.  
  Address Department of Psychology, University of California, Los Angeles, CA 90095, USA. blaisdell@psych.ucla.edu  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1095-9203 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16484500 Approved no  
  Call Number refbase @ user @ Serial 154  
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Author Steelman, S.M.; Michael-Eller, E.M.; Gibbs, P.G.; Potter, G.D. url  doi
openurl 
  Title Meal size and feeding frequency influence serum leptin concentration in yearling horses Type Journal Article
  Year 2006 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.  
  Volume 84 Issue 9 Pages 2391-2398  
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  Abstract (up) Energy is an essential nutrient for all horses, and it is especially important in performance horses, pregnant and lactating mares, and young growing horses. A negative energy balance in horses such as these may result in unsatisfactory performance, decreased fertility, or slow growth. Therefore, ensuring adequate energy intake is an important aspect of the nutritional management of the equine. This study was undertaken to investigate the effects of feeding large, carbohydrate-rich, concentrate meals on the satiety-inducing hormone, leptin. Three groups of yearling horses were rotated through 3 feeding schedules in a replicated 3x3 Latin square design. Horses were fed 2, 3, or 4 times per day (2x, 3x, and 4xfeeding schedules, respectively), each for a period of 11 d, with the total amount of daily feed held constant. Horses were weighed and BCS was determined on the first day of each period. Blood samples were collected before the morning meal on d 1, 4, and 7 of each period. Additionally, blood was sampled for the last 24 h of the 2xand 4xdietary periods. Neither weight nor BCS changed during the study (P = 0.99 and P = 0.28, respectively). Both mean and peak plasma glucose were greatest in 2xhorses (P < 0.05), as were mean areas under the curve. Serum leptin concentration increased in 2xhorses (P < 0.05), but not in horses fed 3 or 4 times daily. Leptin was elevated in horses with greater BCS (P < 0.05) and increased steadily throughout the study (P < 0.05). Data from the 24-h collection indicated that 2xhorses had fluctuations in leptin production throughout the day (P < 0.05), whereas horses fed 4 times daily did not. Overall, this study indicates that feeding horses 2 large concentrate meals daily can increase mean serum leptin concentrations and may cause fluctuations in leptin production over a 24-h period. This departure from baseline leptin concentration has the potential to affect appetite, along with numerous other physiological processes.  
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  Notes 10.2527/jas.2005-281 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3561  
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Author Siniscalchi, M.; Sasso, R.; Pepe, A.M.; Dimatteo, S.; Vallortigara, G.; Quaranta, A. url  doi
openurl 
  Title Catecholamine plasma levels following immune stimulation with rabies vaccine in dogs selected for their paw preferences Type Journal Article
  Year 2010 Publication Neuroscience Letters Abbreviated Journal  
  Volume 476 Issue 3 Pages 142-145  
  Keywords Physiology; Behavior; Lateralization; Catecholamines; Paw preference; Neuro-immune-modulation  
  Abstract (up) Epinephrine and norepinephrine plasma levels were assessed in dogs in relation to paw preference following an immune challenge with rabies vaccine. The results showed that both catecholamines increased after the vaccine administration, confirming the main role of the sympathetic nervous system in the modulation activity between the brain and the immune system. Moreover, ambidextrous dogs showed a significantly higher increase of epinephrine levels 8 days after immunization with respect to right- and left-pawed dogs, suggesting that the biological activity of this molecule could be key for a different immune response with regard to laterality.  
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  ISSN 0304-3940 ISBN Medium  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5788  
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Author Pluhácek, J.; Bartos, L.; Bartosová, J.; Kotrba, R. url  doi
openurl 
  Title Feeding behaviour affects nursing behaviour in captive plains zebra (Equus burchellii) Type Journal Article
  Year 2010 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 128 Issue 1-4 Pages 97-102  
  Keywords Equus burchellii; Suckling; Nursing; Equid; Feeding; Zoo  
  Abstract (up) Equids spend more than half of the day feeding. Lactation is a very demanding form of maternal investment. In an environment such as a zoo, where no grass but several feeding sites are present, conflict between suckling behaviour of the foal and feeding behaviour of the lactating mother should occur. We observed 20 foals of captive plains zebra, Equus burchellii, at the Dvur Králové Zoo, Czech Republic, and collected data concerning suckling events during 17 months of observation. First, we examined whether feeding by the mother while nursing affected suckling behaviour. We found that when the mother was feeding, the proportion of suckling bouts she terminated decreased with increasing age of the foal, whereas it did not change when she was not feeding. This result supported the trade-off between suckling and feeding behaviour which has been reported in other ungulates. Second, we examined what affected interruptions of feeding behaviour of the mother during the suckling bout. The proportion of interruptions of feeding by the mother during nursing increased with increasing age of her foal. This coincides with declining time spent nursing. In addition, younger mothers interrupted their feeding behaviour during suckling bouts more often than older ones. Mothers interrupted feeding during the suckling bout more often when they nursed a daughter than when they nursed a son. The results of our study show that feeding while suckling could reduce parent-offspring conflict and improve welfare of captive foals and mares.  
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  ISSN 0168-1591 ISBN Medium  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5280  
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Author Krueger., K.; Farmer, K. pdf  url
openurl 
  Title Social learning in Horses: Differs from individual learning only in the learning stimulus and not in the learning mechanisms Type Abstract
  Year 2018 Publication 14th Meeting of the Internatinoal Society for Equitation Science Abbreviated Journal 14th Meeting ISES  
  Volume Issue Pages  
  Keywords horse; individual learning; learning mechanisms; learning stimuli; social learning  
  Abstract (up) Equine welfare can be enhanced by applying species specific training. This may incorporate social learning, as horses are highly social and social stimuli are of primary importance. Social learning is comparable to individual learning in its learning mechanisms, differing primarily in the way it is stimulated. Our initial study showed that horses of different breeds (N = 38) follow humans after observing other horses doing so, but only if the observed horse was familiar to and higher ranking than the observer (Fisher's exact test: N = 12, P = 0.003). A second study showed that horses and ponies (N = 25) learned to pull a rope to open a feeding apparatus after observing demonstrations by conspecifics, again, only if the demonstrating horse was older and higher ranking than the observer (Fisher's combination test, N = 3, v2 = 27.71, p = 0.006). Our third approach showed that horses and ponies (N = 24) learned to press a switch to open a feeding apparatus after observing a familiar person (GzLM: N = 24, z = 2.33, P = 0.02). Most recently, we confronted horses and ponies (N = 50) with persons demonstrating different techniques for opening a feeding apparatus. In this study we investigated whether the horses would copy the demonstrators' techniques or apply their own. Here only some horses copied the technique, and most of the successful learners used their mouths irrespective of the demonstrators' postures (Chi Square Test: N = 40, df = 2, &#967;2 = 31.4, p < 0.001). In all the approaches social stimuli elicited learning processes in the test horses, while only a few individuals in the control groups mastered the tasks by individual learning. The following behaviour observed in the initial study may have been facilitated by a social stimuli (social facilitation), and the opening of the feed boxes in the subsequent studies appear to be mostly the result of enhancement (social enhancement). Some horses may have used the social stimuli at first and continued their learning process by individual trial and error. However, the horses were also selective in whom and some in how to copy. This may have been conditioned (socially conditioned) or the result of simple forms of reasoning on the reliability of the particular information provided by demonstrators of certain social ranks or social positions, as high ranking and familiar horses and familiar persons were copied and some imitated exactly.

Lay person message: Traditional riding instructions suggest that horses learn by observing other horses. For example, older, more experienced driving horses are used for initial training of young driving horses. We have shown that horses indeed use learning stimuli provided by other horse, as well as by humans. Horses readily accept stimuli observed in high ranking and familiar horses, and familiar persons. Such stimuli elicit learning processes which are comparable to individual learning. We suggest applying social learning whenever possible, as it is much faster and less stressful than individual learning, where learners experience negative outcomes in trial and error learning.
 
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  Call Number Equine Behaviour @ team @ Serial 6405  
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Author Dugatkin, L.A.; Godin, J.G. doi  openurl
  Title Reversal of female mate choice by copying in the guppy (Poecilia reticulata) Type Journal Article
  Year 1992 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 249 Issue 1325 Pages 179-184  
  Keywords Acclimatization; Animals; *Choice Behavior; Female; Male; Poecilia; *Sexual Behavior, Animal  
  Abstract (up) Ever since Fisher (1958) formalized models of sexual selection, female mate choice has been assumed to be a genetically determined trait. Females, however, may also use social cues to select mates. One such cue might be the mate choice of conspecifics. Here we report the first direct evidence that a female's preference for a particular male can in fact be reversed by social cues. In our experiments using the Trinidadian guppy (Poecilia reticulata), this reversal was mediated by mate-copying opportunities, such that a female (the 'focal' female) is given the opportunity to choose between two males, followed by a period in which she observes a second female (the 'model' female) displaying a preference for the male she herself did not prefer initially. When allowed to choose between the same males a second time, compared with control tests, a significant proportion of focal females reversed their mate choice and copied the preference of the model female. These results provide strong evidence for the role of non-genetic factors in sexual selection and underlie the need for new models of sexual selection that explicitly incorporate both genetic and cultural aspects of mate choice.  
  Address Department of Biology, Mount Allison University, Sackville, New Brunswick, Canada  
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  ISSN 0962-8452 ISBN Medium  
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  Notes PMID:1360679 Approved no  
  Call Number Serial 1824  
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