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	Author	Timney, B.; Keil, K.
	Title	Visual acuity in the horse			Type	Journal Article
	Year	1992	Publication	Vision Research	Abbreviated Journal	Vis. Res.
	Volume	32	Issue	12	Pages	2289-2293
	Keywords	Horse Visual acuity Visual discrimination
	Abstract	We assessed the ease with which horses could learn visual discriminations and measured their resolution acuity. We trained three horses to press their noses against one of two large wooden panels to receive a small food reward. Following training on a series of two-choice discrimination tasks, resolution acuity was measured. Although there was some variability between animals, the best acuity obtained was 23.3 c deg-1. Within the margin of error imposed by limited anatomical data, the obtained values are consistent with predictions based on retinal ganglion cell density estimates and posterior nodal distance/axial length ratios. They suggest that the resolution acuity of the horse is limited by ganglion cell density in the temporal portion of the narrow visual streak.
	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	refbase @ user @			Serial	851
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	Author	Duncan P,
	Title	Zebras, asses, and horses			Type	Book Whole
	Year	1992	Publication	Kelvyn Press USA	Abbreviated Journal
	Volume		Issue		Pages
	Keywords
	Abstract	Provides summaries of the conservation status, biology, and ecology of wild zebras, asses, and horses. The Action Plan presents chapters on taxonomy, genetics, reproductive biology, population dynamics, management, disease and epidemiology, and the importance of developing an assessment methodology that considers the role of equids in ecosystems.
	Address
	Corporate Author				Thesis
	Publisher	Kelvyn Press	Place of Publication	Broadview, Illinois	Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	978-2831700564	Medium
	Area		Expedition		Conference
	Notes	from Professor Hans Klingels Equine Reference List JA -			Approved	yes
	Call Number				Serial	1032
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	Author	Elzenga, J. W,
	Title	Why zebras are striped			Type	Journal Article
	Year	1992	Publication	Swara	Abbreviated Journal	Swara
	Volume	15	Issue	4	Pages	28-30
	Keywords
	Abstract
	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	from Professor Hans Klingels Equine Reference List			Approved	yes
	Call Number				Serial	1068
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	Author	Winkler A,
	Title	The feeding ecology of the Cape Mountain zebra in the Mountain Zebra National Park			Type	Manuscript
	Year	1992	Publication		Abbreviated Journal
	Volume		Issue		Pages
	Keywords
	Abstract
	Address
	Corporate Author				Thesis	Doctoral 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	from Professor Hans Klingels Equine Reference List			Approved	yes
	Call Number				Serial	1713
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	Author	Dugatkin, L.A.; Godin, J.G.
	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	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
	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	0962-8452	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:1360679			Approved	no
	Call Number				Serial	1824
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	Author	Harkins, J.D.; Kamerling, S.G.; Church, G.
	Title	Effect of competition on performance of thoroughbred racehorses			Type	Journal Article
	Year	1992	Publication	Journal of Applied Physiology (Bethesda, Md. : 1985)	Abbreviated Journal	J Appl Physiol
	Volume	72	Issue	3	Pages	836-841
	Keywords	Age Factors; Animals; Anxiety/physiopathology; Competitive Behavior/physiology; Exertion/physiology; Fatigue/physiopathology; Female; Heart Rate; Horses/*physiology; Lactates/blood; Lactic Acid; Male; Sex Characteristics
	Abstract	The effect of competition and the influence of age and sex on performance were examined in a study of 18 Thoroughbred racehorses. The horses performed two solo and two competitive runs at 1,200 and 1,600 m for a total of eight runs. No group ran faster during competition, which may have been a reflection of the quality of horses used for this study and their susceptibility to stress-induced impairment of performance. Males showed no significant difference between competitive and solo run times, whereas females were consistently slower during competition. Males ran significantly faster than females in all runs. There was no difference in run times due to age, which may have been due to the high mean age (5.9 yr) of the group. The slower competitive run times may have occurred because of an earlier onset of fatigue when compared with solo runs. Plasma lactate was significantly greater for the 1,200-m competitive than for the solo runs.
	Address	Department of Veterinary Physiology, Pharmacology, and Toxicology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803
	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	8750-7587	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:1568979			Approved	no
	Call Number	refbase @ user @			Serial	1947
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	Author	Kabuga, J.D.
	Title	Social relationships in N'dama cattle during supplementary feeding			Type	Journal Article
	Year	1992	Publication	Applied Animal Behaviour Science	Abbreviated Journal	Appl. Anim. Behav. Sci.
	Volume	34	Issue	4	Pages	285-290
	Keywords
	Abstract	Social relationships of 30 N'dama cows during supplementary feeding, post-grazing, were studied over a period of 1.5 years. Dominance ranks determined during idling and feeding periods were strongly correlated (Spearman's rank correlation (rs = 0.964, P < 0.01). The number of animals dominated by a cow during feeding was strongly (P < 0.01) related to liveweight (r = 0.822) and age (r = 0.755). Low status cows ate less frequently than medium and high status animals, while middle ranking cows were ejected more frequently from the feed trough than other dominance groups. Animals had preferences in the use of feed troughs, with social rank being the dominant factor determining the location of feed trough space used. Cows of similar status were generally preferred feeding and movement neighbours and antagonists. However, the dominance rank of an animal and its preferred neighbour during idling were not significantly correlated (rs = 0.220, P > 0.05). Voluntary leadership ranks into and out of the pen were, respectively, related closely (P < 0.01) to feeding dominance ranks (rs = 0.661, 0.640) and idling dominance ranks (rs = 0.621, 0.669).
	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 @ room B 3.029			Serial	2033
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	Author	Brunner, D.; Kacelnik, A.; Gibbon, J.
	Title	Optimal foraging and timing processes in the starling, Sturnus vulgaris: effect of inter-capture interval			Type	Journal Article
	Year	1992	Publication	Animal Behaviour.	Abbreviated Journal	Anim. Behav.
	Volume	44	Issue	4	Pages	597-613
	Keywords
	Abstract	Laboratory experiments with starlings, Sturnus vulgaris, were conducted to investigate the interaction between timing and cost-benefit considerations. The design simulated an environment in which food was distributed in patches. Patches contained a random number of food items (N=0-4) separated by a fixed inter-capture interval or fixed interval. All patches ended with sudden depletion. The time elapsed since the last prey capture was the only way to detect the depletion of the patch. Once the patch was depleted a new patch could be reached by travelling between two perches. Three measures of timing were taken: (1) rate of working for food as function of `waiting' time in a patch, (2) the time of the last response in a patch or `giving-in' time, and (3) the time at which travel was initiated or `moving-on' time. The fixed interval that characterized patches was varied between conditions. The mean time of the peak in working rate was consistently centred around the fixed interval, while the other two measures of timing kept a roughly linear relation to the fixed interval, with slope greater than one. In accordance with Scalar Expectancy Theory, variability in the three forms of timing was proportional to the magnitude of the fixed interval. The birds seemed to take account of this increase in variability as shown by the mean value of their giving-up criterion. These results imply that information-processing constraints are important for modelling behavioural optimality.
	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				Serial	2112
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	Author	Caraco, T.; Kacelnik, A.; Mesnick, N.; Smulewitz, M.
	Title	Short-term rate maximization when rewards and delays covary			Type	Journal Article
	Year	1992	Publication	Animal Behaviour.	Abbreviated Journal	Anim. Behav.
	Volume	44	Issue	Part 3	Pages	441-447
	Keywords
	Abstract	In nature foragers must exploit resources that vary randomly in both the energy acquired per item (reward) and the time required to pursue, capture and process an item (delay). Furthermore, rewards and delays associated with particular resources may often covary significantly. An analytical model asks how variance-covariance levels for rewards and delays could influence choice of resources when lack of information or cognitive limitation implies that a consumer attempts to maximize its short-term rate of energy gain. Both greater expected reward and reduced expected delay clearly should enhance preference for a resource. The model predicts that increased delay variance and reduced reward-delay covariance should increase a forager's preference for a resource. A forager should be risk-averse towards reward variance when the reward-delay covariance is positive, but should become risk-prone towards reward variance when the reward-delay covariance is negative.
	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				Serial	2113
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	Author	Kacelnik, A.; Todd, I.A.
	Title	Psychological mechanisms and the Marginal Value Theorem: effect of variability in travel time on patch exploitation			Type	Journal Article
	Year	1992	Publication	Animal Behaviour.	Abbreviated Journal	Anim. Behav.
	Volume	43	Issue	2	Pages	313-322
	Keywords
	Abstract	The Marginal Value Theorem (MVT) describes the behaviour that maximizes the ratio of expected gain over expected foraging time in a patchy environment. When travel time is variable, the MVT rationale and its predictions are sensitive only to the mean travel time and not to the spread or skew of the distribution. Two mechanistic arguments contradict these predictions. First, tests of the MVT have previously shown that there is a disproportionate influence of the last travel time, and second, psychological models of information processing suggest that memory for time intervals is strongly dependent on the scatter of the distribution experienced. These mechanistic concepts, combined with Jensen's inequality, suggest that patch exploitation should decrease as the scatter of the travel distribution increases. In a Skinner box experiment with pigeons, Columba livia, the problem was examined by simulating three environments with identical patches and the same mean travel time, but different travel time variability. Patch exploitation decreased with increasing variance in travel time. The results are used to argue in favour of the inclusion of realistic psychological properties as constraints in functional models of behaviour. Although both the MVT and the mechanistic models account for some features of the results, none of them can explain all the findings.
	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				Serial	2114
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