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Heird, J. C., Lennon, A. M., & Bell, R. W. (1981). Effects of early experience on the learning ability of yearling horses. J. Anim Sci., 53(5), 1204–1209.
Abstract: Twenty-four yearling Quarter Horse fillies were divided into three groups (I) very limited handling, (II) intermediate handling and (III) extensive handling. At about 14 months of age, each horse was preconditioned for 2 weeks and then run in a simple place-learning T-maze test in which it had to locate its feed. Thirty trials were run daily for 20 days, with the location of the feed changed each day. To retire from the maze, a horse had to meet the criterion: 11 correct responses in 12 tries, with the last eight being consecutive. Horses in Group II required the fewest trials to reach criterion. These horses also learned more and had the highest percentage of correct responses (P less than .05). Mean trainability tended to predict learning ability; however, trainability and trials to criterion were not significantly correlated. Mean emotionality scores indicated a tendency for horses in the intermediately handled group to be less emotional than those in Group I or III. Results indicated that horses with an intermediate amount of handling scored higher on an intermediate test of learning. All handled horses scored higher on learning tests than those not handled.
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Langbein, J., Siebert, K., Nuernberg, G., & Manteuffel, G. (2007). The impact of acoustical secondary reinforcement during shape discrimination learning of dwarf goats (Capra hircus). Appl. Anim. Behav. Sci., 103(1-2), 35–44.
Abstract: The use of secondary reinforcement is widely accepted to support operant learning in animals. In farm animals, however, the efficacy of secondary reinforcement has up to now been studied systematically only in horses (“clicker training”), and the results are controversial. We investigated the impact of acoustical secondary reinforcement on voluntary, self-controlled visual discrimination learning of two-dimensional shapes in group-housed dwarf goats (Capra hircus). Learning tests were conducted applying a computer-controlled learning device that was integrated in the animals' home pen. Shapes were presented on a TFT-screen using a four-choice design. Drinking water was used as primary reinforcement. In the control group (Gcontrol, n = 5) animals received only primary reinforcement, whereas in the sound group (Gsound, n = 6) animals got additional acoustical secondary reinforcement. Testing recall of shapes which had been successfully learned by the goats 6 weeks earlier (T1), we found a weak impact of secondary reinforcement on daily learning success (P = 0.07), but not on the number of trials the animals needed to reach the learning criterion (trials to criterion, n.s.). Results in T1 indicated that dwarf goats did not instantly recall previously learned shapes, but, re-learned within 250-450 trials. When learning a set of new shapes (T2), there was a strong influence of secondary reinforcement on daily learning success and on trials to criterion. Animals in Gsound reached the learning criterion earlier (P < 0.05) and needed fewer trials (1320 versus 3700; P < 0.01), compared to animals in Gcontrol. Results suggest that acoustical secondary reinforcement supports visual discrimination learning of dwarf goats, especially when the task is new and the salience of S+ is low.
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Petherick, J. C., Seawright, E., & Waddington, D. (1993). Influence of motivational state on choice of food or a dustbathing/foraging substrate by domestic hens. Behav. Process., 28(3), 209–220.
Abstract: Domestic hens were trained to run a Y-maze and make an association between differently coloured doorways and access to food pellets or sand. The hens were tested for their choice of doorway when the goals were not visible from the choice point and when they were food or sand deprived. Hens made the choice appropriate to their deprivation state (correct choice) significantly more often for food than sand and were faster at choosing and entering the goal box when food deprived. In a follow up experiment, the goals were visible from the choice point. Again the hens chose correctly significantly more often when food than sand deprived and made the choice and entered the goal box faster when food deprived. Thus, failure to choose sand in the first experiment was not due to an inability to learn the association, but appears to result from a strong motivation to feed in the Y-maze, even when not food deprived, and a weak motivation to dustbathe or forage, even when sand deprived.
Keywords: Food; Learning; Litter; Motivation; Poultry; Preference
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Petherick, J. C., Waddington, D., & Duncan, I. J. H. (1991). Learning to gain access to a foraging and dustbathing substrate by domestic fowl: is `out of sight out of mind'? Behav. Process., 22(3), 213–226.
Abstract: Domestic fowl were deprived of the opportunity to perform litter-related behaviour for three or four days and were tested in a Y-maze (which they had previously been trained to run) for their ability to associate a coloured cue with gaining access to peat. When the goal boxes were within sight of the choice point, most birds chose peat. However, when the birds had to rely solely on the coloured cue only one bird from 12 showed learning. However, the birds seemed to have some expectation of a reward, as they ran faster if, on the previous trial, they had chosen peat. The inability of the birds to learn the association may have been an artefact of the schedule of deprivation and testing, for when they were hungry and tested in the same way they were again unable to learn an association between the same coloured cue and food reward. The experiment with peat was repeated using “massed” trials (several trials in immediate succession) during training and testing and six from 15 birds showed learning. These results suggest that the initial failure to learn was probably due to the training and testing schedule, that access to peat appears to be rewarding and that hens can learn an association between an abstract cue and a rewarding consequence. This is consistent with the possibility that domestic fowls may have some cognitive representation of peat when it is out of sight.
Keywords: Domestic fowl; Dustbathing; Welfare; Learning; Cognition
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Simpson, B. S. (2002). Neonatal foal handling. Appl. Anim. Behav. Sci., 78(2-4), 303–317.
Abstract: Recent interest has focused on the advantage of intensively handling young foals as a means of producing more tractable horses, accustomed to humans and receptive to training. To date, the effect of this intensive handling, dubbed “imprint training” in the popular literature, has not been tested. The present study compares seven foals handled intensively as neonates with eight untreated controls. The handling protocol started from 2-8 h after birth and continued daily for a total of 5 days. The protocol consisted of a series of stimuli and experiences that were each repeated until the foal no longer resisted or reacted negatively. Subsequently, foals were tested before weaning, at 4 months of age. Results indicated that handled foals (HF) ranked higher than control foals (CF) in subjective ratings of calmness (*P<0.0117) and friendliness (*P<0.0001) and in several specific handling tasks (venipuncture *P<0.0220; placing in stock *P<0.0128). Although, in approach tests all foals but one allowed approach of a person to 4 m, significantly more HF approached the person than CF (P<0.0080). In stimulus tests, foals were presented specific stimuli to which they had been tested as neonates. Two of eight CF were too unruly and dangerous to test. Of foals that could be tested, CF required significantly more time to hook-up a heart rate monitor (**P<0.0055). Split-plot analysis indicated that HF had lower heart rates to initial left-sided stimuli, presented first, than CF (*P<0.0421). In response to right-sided stimuli, heart rate scores of CF were not significantly different from HF (P<0.2259), suggesting reduced reactivity over time due to a learning effect. Behavioral responses to specific stimuli did not differ between CF and HF, suggesting that neonatal handling has a general rather than specific effect on subsequent behavior. Cortisol concentrations were measured before and after testing and the difference calculated. All foals had higher post-testing levels than pre-testing levels. There was a significant difference between HF and CF, indicating greater reactivity among the CF (*P<0.050). In general, the results indicated that foals handled as neonates were more tractable and less reactive. Specific neonatal handling tasks, such as sticking a finger up the foal's nose or patting the bottom of the foot, seemed to have no beneficial effect on related tasks such as passing a nasogastric tube or tapping with a farrier's hammer at 4 months of age. Mechanisms for the observed effect of neonatal handling require further investigation.
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McCall, C. A., Salters, M. A., & Simpson, S. M. (1993). Relationship between number of conditioning trials per training session and avoidance learning in horses. Appl. Anim. Behav. Sci., 36(4), 291–299.
Abstract: Sixteen horses were used to determine if number of trials given per training session (5, 10, 15 or 20) affected learning performance in an avoidance conditioning task. The horse had to move from one side of a test pen to the other during an auditory cue presentation to avoid aversive stimulation. A pen 8 mx3.6 m, divided into two equal sections by a 13-cm diameter plastic pipe lying on the ground, was used as the test pen. Painted plywood panels were fastened to the fence in half the pen to help horses distinguish visually between the two parts. A 10-s auditory cue was used as a signal for horses to move from one side of the test pen to the other. A 20-s intertrial interval was used. Training sessions were conducted every third day. Each trial was recorded as an avoidance (the horse completed the task during auditory cue presentation and avoided aversive stimulus) or an error (the horse received aversive stimulus). After completing ten consecutive avoidances (criterion), the horse was removed from the study. Numbers of training sessions, trials, avoidances and errors until reaching criterion were recorded for each horse. Horses varied greatly within these variables with ranges of 3-18 sessions, 37-121 trials, 20-68 avoidances and 17-53 errors to criterion. No differences were detected (P>0.05) in the number of conditioning trials per training session (treatment) for the mean number of trials, avoidances or errors to criterion. Number of training sessions to criterion differed (P<0.01) among treatments, indicating that an optimum number of learning trials per training session might exist. Mean sessions to criterion for horses receiving 5, 10, 15 and 20 trials per session were 15.1+/-1.3, 5.8+/-1.1, 5.3+/-1.1 and 4.6+/-1.1, respectively. Regression analysis indicated that 16.2 trials per training session would minimize number of sessions to criterion. Although it is widely assumed that learning efficiency in horses is decreased when intense activity is concentrated into a small number of sessions, these results indicate that moderate repetition of training activities is needed for efficient learning.
Keywords: Horse; Learning; Avoidance conditioning
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Tomasello, M., Davis-Dasilva, M., Camak, L., & Bard, K. (1987). Observational learning of tool-use by young chimpanzees. Human Evolution, 2(2), 175–183.
Abstract: In the current study two groups of young chimpanzees (4–6 and 8–9 years old) were given a T-bar and a food item that could only be reached by using the T-bar. Experimental subjects were given the opportunity to observe an adult using the stick as a tool to obtain the food; control subjects were exposed to the adult but were given no demonstration. Subjects in the older group did not learn to use the tool. Subjects in the younger group who were exposed to the demonstrator learned to use the stick as a tool much more readily than those who were not. None of the subjects demonstrated an ability to imitatively copy the demonstrator's precise behavioral strategies. More than simple stimulus enhancement was involved, however, since both groups manipulated the T-bar, but only experimental subjects used it in its function as a tool. Our findings complement naturalistic observations in suggesting that chimpanzee tool-use is in some sense «culturally transmitted» — though perhaps not in the same sense as social-conventional behaviors for which precise copying of conspecifics is crucial.
Keywords: Chimpanzees; Observational Learning; Tool-Use
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Boyd, R., & Richerson, P. J. (1995). Why does culture increase human adaptability? Ethol. a. Sociob., 16(2), 125–143.
Abstract: It is often argued that culture is adaptive because it allows people to acquire useful information without costly learning. In a recent paper Rogers (1989) analyzed a simple mathematical model that showed that this argument is wrong. Here we show that Rogers' result is robust. As long as the only benefit of social learning is that imitators avoid learning costs, social learning does not increase average fitness. However, we also show that social learning can be adaptive if it makes individual learning more accurate or less costly.
Keywords: Social learning; Adaptation; Culture; Sociobiology
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Giraldeau, L. - A., Valone, T., J., & Templeton, J., J. (2002). Potential disadvantages of using socially acquired information. Phil. Trans. Biol. Sci., 357(1427), 1559–1566.
Abstract: The acquisition and use of socially acquired information is commonly assumed to be profitable. We challenge this assumption by exploring hypothetical scenarios where the use of such information either provides no benefit or can actually be costly. First, we show that the level of incompatibility between the acquisition of personal and socially acquired information will directly affect the extent to which the use of socially acquired information can be profitable. When these two sources of information cannot be acquired simultaneously, there may be no benefit to socially acquired information. Second, we assume that a solitary individual's behavioural decisions will be based on cues revealed by its own interactions with the environment. However, in many cases, for social animals the only socially acquired information available to individuals is the behavioural actions of others that expose their decisions, rather than the cues on which these decisions were based. We argue that in such a situation the use of socially acquired information can lead to informational cascades that sometimes result in sub-optimal behaviour. From this theory of informational cascades, we predict that when erroneous cascades are costly, individuals should pay attention only to socially generated cues and not behavioural decisions. We suggest three scenarios that might be examples of informational cascades in nature.
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Rogers, A. R. (1988). Does Biology Constrain Culture? Am Anthropol, 90(4), 819–831.
Abstract: Most social scientists would agree that the capacity for human culture was probably fashioned by natural selection, but they disagree about the implications of this supposition. Some believe that natural selection imposes important constraints on the ways in which culture can vary, while others believe that any such constraints must be negligible. This article employs a “thought experiment” to demonstrate that neither of these positions can be justified by appeal to general properties of culture or of evolution. Natural selection can produce mechanisms of cultural transmission that are neither adaptive nor consistent with the predictions of acultural evolutionary models (those ignoring cultural evolution). On the other hand, natural selection can also produce mechanisms of cultural transmission that are highly consistent with acultural models. Thus, neither side of the sociobiology debate is justified in dismissing the arguments of the other. Natural selection may impose significant constraints on some human behaviors, but negligible constraints on others. Models of simultaneous genetic/cultural evolution will be useful in identifying domains in which acultural evolutionary models are, and are not, likely to be useful.
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