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	Author	Huber, R.; van Staaden, M.J.; Kaufman, L.S.; Liem, K.F.
	Title	Microhabitat Use, Trophic Patterns, and the Evolution of Brain Structure in African Cichlids			Type	Journal Article
	Year	1997	Publication	Brain, Behavior and Evolution	Abbreviated Journal	Brain Behav Evol
	Volume	50	Issue	3	Pages	167-182
	Keywords
	Abstract	The species assemblages of cichlids in the three largest African Great Lakes are among the richest concentrations of vertebrate species on earth. The faunas are broadly similar in terms of trophic diversity, species richness, rates of endemism, and taxonomic composition, yet they are historically independent of each other. Hence, they offer a true and unique evolutionary experiment to test hypotheses concerning the mutual dependencies of ecology and brain morphology. We examined the brains of 189 species of cichlids from the three large lakes: Victoria, Tanganyika, and Malawi. A first paper demonstrated that patterns of evolutionary change in cichlid brain morphology are similar across taxonomic boundaries as well as across the three lakes [van Staaden et al., 1995 ZACS 98: 165–178]. Here we report a close relationship between the relative sizes of various brain structures and variables related to the utilization of habitat and prey. Causality is difficult to assign in this context, nonetheless, prey size and agility, turbidity levels, depth, and substrate complexity are all highly predictive of variation in brain structure. Areas associated with primary sensory functions such as vision and taste relate significantly to differences in feeding habits. Turbidity and depth are closely associated with differences in eye size, and large eyes are associated with species that pick plankton from the water column. Piscivorous taxa and others that utilize motile prey are characterized by a well developed optic tectum and a large cerebellum compared to species that prey on molluscs or plants. Structures relating to taste are well developed in species feeding on benthos over muddy or sandy substrates. The data militated against the existence of compensatory changes in brain structure. Thus enhanced development of a particular function is generally not accompanied by a parallel reduction of structures related to other modalities. Although genetic and environmental influences during ontogeny of the brain cannot be isolated, this study provides a rich source of hypotheses concerning the way the nervous system functions under various environmental conditions and how it has responded to natural selection.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0006-8977	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Equine Behaviour @ team @			Serial	5454
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	Author	Gallagher, M.; Rapp, P.R.
	Title	The Use Of Animal Models To Study The Effects Of Aging On Cognition			Type	Journal Article
	Year	1997	Publication	Annual Review of Psychology	Abbreviated Journal
	Volume	48	Issue	1	Pages	339-370
	Keywords
	Abstract	This review addresses the importance of animal models for understanding the effects of normal aging on the brain and cognitive functions. First, studies of laboratory animals can help to distinguish between healthy aging and pathological conditions that may contribute to cognitive decline late in life. Second, research on individual differences in aging, a theme of interest in studies of elderly human beings, can be advanced by the experimental control afforded in the use of animal models. The review offers a neuropsychological framework to compare the effects of aging in human beings, monkeys, and rodents. We consider aging in relation to the role of the medial temporal lobe in memory, the information processing functions of the prefrontal cortex in the strategic use of memory, and the regulation of attention by distributed neural circuitry. We also provide an overview of the neurobiological effects of aging that may account for alterations in psychological functions.
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	Publisher		Place of Publication		Editor
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	Notes				Approved	no
	Call Number	Equine Behaviour @ team @			Serial	2971
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	Author	Szenci, O.; Palme, R.; Taverne, M.A.; Varga, J.; Meersma, N.; Wissink, E.
	Title	Evaluation of false ultrasonographic pregnancy diagnoses in sows by measuring the concentration of unconjugated estrogens in feces			Type	Journal Article
	Year	1997	Publication	Theriogenology	Abbreviated Journal	Theriogenology
	Volume	48	Issue	5	Pages	873-882
	Keywords
	Abstract	On Days 26, 28, and 30 after AI, ultrasonographic pregnancy diagnoses were performed on 207 gilts and sows by using a 3.5 MHz linear-array transducer. Fecal samples were taken from the rectum after each ultrasonographic examination, and the concentrations of unconjugated estrogens in selected samples (n = 73) were measured by RIA. Fecal unconjugated estrogen concentration of 11.7 ng/g feces or higher was indicative of pregnancy. The overall sensitivity and specificity of the ultrasonographic test was 99% for farrowing sows and 73.1% for nonfarrowing sows. With one exception, sows with a false negative diagnosis by ultrasonography on Day 26 were correctly diagnosed pregnant by elevated fecal unconjugated estrogens or repeated ultrasonographic examinations on Days 28 or 30. Return to estrus around the sampling period may cause false positive results in the unconjugated estrogen assay, while early embryonic mortality can result in false positive diagnoses in both the ultrasonographic test and estrogen assay. Although there was a positive correlation between the concentrations of unconjugated estrogens in the feces and litter size at farrowing in the selected sows, it seems very unlikely that fecal estrogens can provide an accurate tool for predicting litter size.
	Address	University of Veterinary Science, Department of Obstetrics and Reproduction H-1400 Budapest, P.O. Box 2, Hungary
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
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	Series Volume		Series Issue		Edition
	ISSN	0093-691X	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:16728179			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	4077
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	Author	de Waal, F.B.; Seres, M.
	Title	Propagation of handclasp grooming among captive chimpanzees			Type	Journal Article
	Year	1997	Publication	American journal of primatology	Abbreviated Journal	Am. J. Primatol.
	Volume	43	Issue	4	Pages	339-346
	Keywords	Animals; Family Relations; Female; Grooming; Learning; Male; Pan troglodytes/psychology; *Social Behavior
	Abstract	A grooming posture previously reported for two wild chimpanzee (Pan troglodytes) communities developed spontaneously in a captive group of the same species. This offered a unique opportunity to follow the propagation of a new social custom. The posture consists of two partners grasping hands--either both right hands or both left hands--and raising the arms in an A-frame above their heads while mutually grooming with their free hands. The propagation of this pattern was followed over a 5 year period. In the beginning, handclasps were always initiated by the same adult female. This female initiated the posture mainly with her adult female kin. In subsequent years, these relatives became frequent participants in the posture with each other as well as with nonrelatives. Over the years the posture increased in frequency and duration and spread to the majority of adults and also to a few adolescents and older juveniles. The pattern persisted after removal of the apparent originator.
	Address	Yerkes Primate Center, Emory University, Atlanta, GA 30329, USA. dewaal@emory.edu
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0275-2565	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:9403098			Approved	no
	Call Number	refbase @ user @			Serial	202
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	Author	Aureli, F.; de Waal, F.B.
	Title	Inhibition of social behavior in chimpanzees under high-density conditions			Type	Journal Article
	Year	1997	Publication	American journal of primatology	Abbreviated Journal	Am. J. Primatol.
	Volume	41	Issue	3	Pages	213-228
	Keywords	Aggression/psychology; Animals; Behavior, Animal; Crowding; Female; Male; Pan troglodytes/psychology; Population Density; *Social Environment; Stress, Psychological
	Abstract	This is the first study to investigate the short-term effects of high population density on captive chimpanzees (Pan troglodytes). Subjects of the study were 45 chimpanzees living in five different groups at the Yerkes Regional Primate Research Center. The groups were observed under two conditions: 1) when they had access to both the indoor and outdoor sections of their enclosures; 2) during cold days when they were locked into the indoor runs, which reduced the available space by more than half. Under the high-density condition, allogrooming and submissive greetings decreased, but juvenile play increased. Remarkably, the rate of various forms of agonistic behavior, such as aggression, bluff charge, bluff display, and hooting, occurred less frequently under the high-density condition. This general decrease in adult social activity, including agonistic behavior, can be interpreted as an inhibition strategy to reduce opportunities for conflict when interindividual distances are reduced. This strategy is probably effective only in the short run, however. Behavioral indicators of anxiety, such as rough scratching and yawning, showed elevated rates, suggesting increased social tension under the high-density condition.
	Address	Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0275-2565	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:9057966			Approved	no
	Call Number	refbase @ user @			Serial	203
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	Author	Monard, A.-M.; Duncan, P.; Fritz, H.; Feh, C.
	Title	Variations in the birth sex ratio and neonatal mortality in a natural herd of horses			Type	Journal Article
	Year	1997	Publication	Behavioral Ecology and Sociobiology	Abbreviated Journal	Behav. Ecol. Sociobiol.
	Volume	41	Issue	4	Pages	243-249
	Keywords
	Abstract	Variations in birth sex ratios and sex differences in juvenile mortality occur in a number of mammalian species, and in many cases have been linked to resource availability. Most of these biases in offspring sex ratios concern polygynous species with pronounced sexual dimorphism, and where females only are philopatric. Data on species with unusual life-history strategies, such as slight sexual dimorphism or dispersal by both sexes, are of particular interest. In this study of a natural herd of horses (Equus caballus) which experienced an eruptive cycle, and therefore a period of nutritional stress, male offspring had higher neonatal mortality rates in nutritionally poor years than in good ones, whereas “year quality” had no effect on the mortality of female offspring; year quality could therefore be used by mares as predictor of sex-specific offspring survival. We show that the environmental conditions that predicted lower survival of males were negatively related to their production: the birth sex ratio the following year was female-biased; and mares were less likely to produce a son when they had produced a son the preceding year. There was no significant effect of mother's parity, age or rank, or the timing of conception or birth on offspring sex ratios. The mechanism leading to biases in the birth sex ratio could have been the loss of male embryos by mares that did not foal. As there was no evidence for selective abortion of male foetuses in females that did foal the next year, it is not necessary to invoke maternal adjustment, though this remains a possibility. Finally, there was a suggestion that male offspring were more costly to raise than females, since mothers that reared a son in poor years tended to experience an increase in the interbirth interval between their two subsequent offspring.
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	Notes				Approved	no
	Call Number	Equine Behaviour @ team @			Serial	2388
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	Author	Le Scolan, N.; Hausberger, M.; Wolff, A.
	Title	Stability over situations in temperamental traits of horses as revealed by experimental and scoring approaches			Type	Journal Article
	Year	1997	Publication	Behavioural Processes	Abbreviated Journal	Behav. Process.
	Volume	41	Issue	3	Pages	257-266
	Keywords	Behavioural tests; Horse; Ratings; Temperament
	Abstract	Individual behavioural reactions of adult horses in a variety of experimental tests were compared with ratings by riding teachers. The tests were made in a non working situation, with the animals being released in an arena, a box (arena test, new object test, learning tests) or handled (new object/handling situation). The traits rated by teachers were fearfulness, nervousness, gregariousness and learning abilities at work (ridden or handled). Despite a great homogeneity in the reactions exhibited by the horses in the different situations, large individual differences were present. Correlations appeared between the reactivity in the arena test and the score of gregariousness, between the reactivity in the novel object test and the rating of nervousness when ridden, between the results in the handling test and the rating of general fearfulness and between the ability to memorise an instrumental task and the score of general learning ability. Such results strengthen the idea that there are underlying behavioural dispositions that are stable across situations and that the experimental tests may be good predictors of the temperament in untrained animals.
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
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	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3591
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	Author	Beaugrand, J.P
	Title	Relative importance of initial individual differences, agonistic experience, and assessment accuracy during hierarchy formation: a simulation study			Type	Journal Article
	Year	1997	Publication	Behavioural Processes	Abbreviated Journal	Behav. Process.
	Volume	41	Issue		Pages	177-192
	Keywords	Dominance; Hierarchy formation; RHP; Agonistic experience; Assessment; Self-organization; Simulation
	Abstract	This simulation study explores some conditions leading to transitivity within dominance orders. Combinations of three parameters were varied to study their consequences upon hierarchy formation and upon the degree of linearity of resultant structures. The factors studied were: (1) the importance of initial resource holding potentials (RHPs); (2) changes brought in RHPs by successive victories and defeats; and (3) accuracy of RHP assessment made by opponents. Results show that initial differences in RHP always lead to perfectly transitive chains whose rank order reflects the importance of initial differences. Even when simulated animals make important errors while assessing each other during round robin tournaments, emerging dominance structures are perfectly linear and ranks obtained in the structure are highly correlated with initial values in RHPs. Moreover, accumulated experiences of victory and/or defeat alone always lead to perfectly linear hierarchies. Their combination with initial individual differences in RHP led to the same conclusion. Even when assessment was far from being perfect, not only perfect chains were formed but initial values in RHPs significantly influenced rank order when the contribution of victory and defeat to RHP was relatively unimportant. The higher the importance of victory and defeat to RHP as compared to that of initial RHP values, the lower was the correlation between initial RHP values and the ranks order reached by individuals in the resultant hierarchies. In general also, the lower the variation within initial RHPs, the lower was the correlation between initial RHPs and ranks in the hierarchy. At a given level of initial RHP dispersion, increasing the contribution of victory and defeat to RHP diminished the correlation between initial RHP values and obtained ranks. In addition, inaccurate assessment reduced the overall correlation, especially when dispersion of initial RHP values was low and the contribution of victory and defeat relatively unimportant. These results shed some light on the controversy about the respective roles of initial individual attributes and that of patterns of resolution in the formation of animal hierarchies. We present the emergence of social order within closed systems as those simulated here as a case of self-organization.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Equine Behaviour @ team @			Serial	4290
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	Author	Beaugrand, J.P.
	Title	Relative importance of initial individual differences, victory and defeat experiences, and assessment accuracy during hierarchy formation: A simulation study			Type	Miscellaneous
	Year	1997	Publication	Cogprints	Abbreviated Journal
	Volume	41	Issue		Pages	177-192
	Keywords	Dominance; Hierarchy formation; RHP; agonistic experience; Assessment; Self-organization; Simulation
	Abstract	This simulation study explores some conditions leading to transitivity within dominance orders. Combinations of three parameters were varied to study their consequences upon hierarchy formation and upon the degree of linearity of resultant structures. The factors studied were (i) the importance of initial Resource Holding Potentials (RHPs) , (ii) changes brought in RHPs by successive victories and defeats, and (iii) accuracy of RHP assessment made by opponents. Results show that initial differences in RHP always lead to perfectly transitive chains whose rank order reflects the importance of initial differences. Even when simulated animals make important errors while assessing each other during round robin tournaments, emerging dominance structures are perfectly linear and ranks obtained in the structure are highly correlated with initial values in RHPs. Moreover, accumulated experiences of victory and/or defeat alone always lead to perfectly linear hierarchies. Their combination with initial individual differences in RHP led to the same conclusion. Even when assessment was far from being perfect, not only perfect chains were formed but initial values in RHPs significantly influenced rank order when the contribution of victory and defeat to RHP was relatively unimportant. The higher the importance of victory and defeat to RHP as compared to that of initial RHP values, the lower was the correlation between initial RHP values and the ranks order reached by individuals in the resultant hierarchies. In general also, the lower the variation within initial RHPs, the lower was the correlation between initial RHPs and ranks in the hierarchy. At a given level of initial RHP dispersion, increasing the contribution of victory and defeat to RHP diminished the correlation between initial RHP values and obtained ranks. In addition, inaccurate assessment reduced the overall correlation, especially when dispersion of initial RHP values was low and the contribution of victory and defeat was high. These results shed some light on the controversy about the respective roles of initial individual attributes and that of patterns of resolution in the formation of animal hierarchies. We present the emergence of social order within closed systems as those simulated here as a case of self-organization.
	Address
	Corporate Author				Thesis
	Publisher	Elsevier	Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Equine Behaviour @ team @ cogprints:1965			Serial	4291
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	Author	Sterck, E.; Watts, D.; van Schaik, C.
	Title	The evolution of female social relationships in nonhuman primates			Type	Journal Article
	Year	1997	Publication	Behavioral Ecology and Sociobiology	Abbreviated Journal	Behav. Ecol. Sociobiol.
	Volume	41	Issue	5	Pages	291-309
	Keywords	ecology; matrilocal; primate; social; theory
	Abstract	Considerable interspeci®c variation in female social relationships occurs in gregarious primates, particularly with regard to agonism and cooperation between females and to the quality of female relationships with males. This variation exists alongside variation in female philopatry and dispersal. Socioecological theories have tried to explain variation in female-female social relationships from an evolutionary perspective focused on ecological factors, notably predation and food distribution. According to the current ``ecological model'', predation risk forces females of most diurnal primate species to live in groups; the strength of the contest component of competition for resources within and between groups then largely determines social relationships between females. Social elationships among gregarious females are here characterized as DispersalEgalitarian, Resident-Nepotistic, Resident-Nepotistic-Tolerant, or Resident-Egalitarian. This ecological model has successfully explained ierences in the occurrence of formal submission signals, decided dominance relation ships, coalitions and female philopatry. Group size and female rank generally aect female reproduction success as the model predicts, and studies of closely related species in dierent ecological circumstances underscore the importance of the model. Some cases, however, can only be explained when we extend the model to incorporate the eects of infanticide risk and habitat saturation. We review evidence in support of the ecological model and test the power of alternative models that invoke between-group competition, forced female philopatry, demographic female recruitment, male interventions into female aggression, and male harassment. Not one of these models can replace the ecological model, which already encompasses the between-group competition. Currently the best model, which explains several phenomena that the ecological model does not, is a ``socioecological model'' based on the combined importance of ecological factors, habitat saturation and infanticide avoidance. We note some points of similarity and divergence with other mammalian taxa; these remain to be explored in detail.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
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	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	Equine Behaviour @ team @			Serial	5227
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