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Tomasello, M. (1996). Do apes ape? In C. M. Heyes, & B. G. Galef (Eds.), Social learning in animals: the roots of culture (pp. 319–346). London: Academic Press.
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Kruska, D. (1996). The effect of domestication on brain size and composition in the mink (Mustela vison). J Zool, 239.
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Meriggi, A., & Lovari, S. (1996). A Review of Wolf Predation in Southern Europe: Does the Wolf Prefer Wild Prey to Livestock? J. Appl. Ecol, 33, 1561–1571.
Abstract: 1. The recent recovery of the wolf in southern Europe has not yet removed the risk
of local extinction. Wolf populations are fragmented and often comprise fewer than 500 individuals. In North America, northern and eastern Europe, wolves feed maiiily on wild herbivores. In southern Europe, this canid has apparently adapted to feed also on fruit, rubbish, livestock, small and medium-size mammals. 2. The main conservation problem lies with predation o n domestic ~ingulates,w liich leads to extensive killing of wolves. The reintroduction of wild large herbivores has been advocated as a means of reducing attacks on livestock, but predatiori on the latter may remain high if domestic ungulates are locally abundant. 3. Our synthesis of 15 studies, published in the last 15 years, on food habits of the wolf in southern Europe, has shown that ungulates have been the main diet component overall. A significant inverse correlation was found between the occurrence (%) of wild and domestic ungulates in the diet. The presence of relatively few wild ungulate species was necessary to reduce predation on livestock. 4. Selection of wild and domestic ungulate prey was influenced mainly by their local abundance, but also by their accessibility. Feeding dependence on rubbish was local and rare. In Italy, the consumption of riibbish/fruit and that of ungulates was significantly negatively correlated. Diet breadth increased as the presence of large prey in tlie diet decreased. 5. The simultaneous reintroduction of severa1 wild ungulate species is likely to reduce predation on livestock and may prove to be one of the most effective conservation measures. |
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Worden, R. P. (1996). Primate social intelligence. Cognit. Sci., 20(4), 579–616.
Abstract: A computational theory of primate social intelligence is proposed in which primates represent social situations internally by discrete symbol structures, called scripts. Three well-defined computational operations on scripts are sufficient to support social learning, planning, and prediction. This gives a formal, predictive model with which to analyse how primate social knowledge is acquired, as well as how it is used. The theory is compared with primate data, such as Cheney and Seyfarth's observations of vervet monkeys. It gives simple, understandable script-based analyses of many observed phenomena--such as the recognition and use of kin relations, learning of alarm calls, habituation to calls, knowledge of rank, tactical deception, and attachment behaviour. I argue that a tight, concise theory of social cognition, such as script theory, is needed to explain the rapid learning and social guile seen in primates. It also has the benefits of simplicity and testability. The extension of scripts to incorporate a primate theory of mind is described in a subsequent paper.
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Beerda, B., Schilder, M. B. H., Janssen, N. S. C. R. M., & Mol, J. A. (1996). The Use of Saliva Cortisol, Urinary Cortisol, and Catecholamine Measurements for a Noninvasive Assessment of Stress Responses in Dogs. Horm. Behav., 30(3), 272–279.
Abstract: A problem in assessing animal welfare is that collecting data in itself may be stressful to the animals. Therefore, noninvasive methods for collecting data have to be devised and tested. A first step in investigating saliva cortisol, urinary cortisol, and urinary catecholamine as noninvasive indicators of canine well-being is the validation of these hormonal measures as alternatives for those in plasma. Using a model of insulin (0.2 U/kg)-induced hypoglycemia, we report on stress-induced responses in saliva cortisol, urinary cortisol, and urinary catacholamines relative to cortisol and catecholamine responses in plasma. Hypoglycemia in six dogs induced significant (P< 0.05) increases in plasma cortisol and adrenaline but not noradrenaline. Saliva cortisol responses expressed as net area under the response curve correlated significantly with plasma cortisol responses (r> 0.92). Saliva cortisol levels measured 7 to 12% of plasma cortisol concentrations. Cortisol/creatinine ratios in urine were significantly higher when voided after insulin administeration, compared to when voided after saline treatment. Insulin-induced increments in cortisol/creatinine ratios were nonsignificant when urine samples were assayed after dichloromethane extraction. Although urinary adrenaline/creatinine (A/C) ratios were significantly correlated with maximum plasma adrenaline values after insulin administration, A/C ratios did not differ significantly between insulin and saline treatment. The present experiment provides strong support for using saliva sampling and urine collection as noninvasive methods to establish stress-induced cortisol responses. For measuring acute plasma adrenaline responses, measuring A/C ratios may not be a valid alternative.
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Barnes, J. I., & Jager, J. L. V. de. (1996). Economic and financial incentives for wildlife use on private land in Namibia and the implications for policy. S. Afr. J. Wildl. Res, 26(2), 37–46.
Abstract: Abstract
Aggregate estimates for wildlife populations and species diversity on private land in Namibia were made for 1972 and 1992, using questionnaire surveys. Numbers of species and biomass appear to have increased by some 80 percent, or three percent per annum over the period. The number of game species recorded increased by 44 percent. Cost – benefit analysis models were developed and used to analyse economic and financial efficiency of land use involving wildlife on private land. Financial profitability was generally low with both livestock – game production for consumptive use and wildlife production for non-consumptive use. However these activities appear to be economically efficient, and result in a positive contribution to National Income. The results suggest that there are financial incentives for private landholders to group together and form large scale conservancies. The latter benefit from economies of scale which make them more financially profitable and robust, and also more economically efficient, than ranches. Wildlife production for non-consumptive wildlife viewing was found to yield greater economic net value added per unit of land than livestock – wildlife production for consumptive use. This was particularly the case at the larger conservancy scale of operation. Aggregate estimates, in 1994 prices, of the annual net value added to National Income from wildlife use on private land are N$ 30.6 million in 1972 and N$ 56 million in 1992. The economic value of wildlife use as a proportion of the economic value of all private land rangeland uses appears to have risen from five percent to eleven percent over the twenty year period. Current policy to promote the development of wildlife conservancies appears to be economically sound, particularly where these are aimed at eventual conversion to wildlife-based tourism uses. _________________________ |
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Phillips, K. (1996). Natural conceptual behavior in squirrel monkeys (saimiri sciureus): An experimental investigation. Primates, 37(3), 327–332.
Abstract: Abstract Natural conceptual discriminations have been tested in many different species, including pigeons and a variety of non-human primates. The ability of four male squirrel monkeys (Saimiri sciureus) to learn and use the natural concept “squirrel monkey” was investigated in this study. After a training phase, subjects were presented with novel stimuli in transfer and test trials. All subjects performed at a rate significantly above chance on the first test trial (p<.001), indicating that squirrel monkeys can utilize natural concepts in the laboratory.
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Tebbich, S., Taborsky, M., & Winkler, H. (1996). Social manipulation causes cooperation in keas.52(1), 1–10.
Abstract: Abstract. This study assessed whether keas,Nestor notabilis, are able to cooperate in an instrumental task. Seven birds of a captive group were tested in group situations and in dyads. At least two individuals had to manipulate an apparatus to obtain food but only one participant was rewarded. One bird had to push down a lever to enable another one to collect food from a box. The distribution of the two different roles was clearly dependent on hierarchy. The higher ranking individual always obtained the reward and each bird changed its role according to dominance status. Owing to the non-linear hierarchy in the group, each bird participating in cooperative interactions had at least one submissive partner. Therefore, in group situations the reward was distributed symmetrically and cooperation was persistent. In dyadic test situations, three individual keas aggressively manipulated their respective subordinate partners to open the apparatus. Their dominance status enabled them to force cooperation.
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Brunner, D., Kacelnik, A., & Gibbon, J. (1996). Memory for inter-reinforcement interval variability and patch departure decisions in the starling,Sturnus vulgaris. Anim. Behav., 51(5), 1025–1045.
Abstract: An experiment with starlings was conducted to investigate the effect of variability in inter-reinforcement intervals on foraging decisions. The experimental design simulated an environment in which food was distributed in patches. Patches contained zero to four food items which could be collected by pecking at a key. All patches ended with sudden depletion. The time elapsed since the last reinforcement was the only way to detect the depletion of the patch. Once a patch was depleted, a new patch could be reached by completion of a travel requirement of 20 flights between two perches. Key pecks within a patch and the time of the last response in a patch (giving-in time) were recorded. The level of variability in the inter-reinforcement intervals was varied between different conditions. An increase in inter-reinforcement interval variability resulted in a flattening of response rate functions and giving-in time distributions, and in more asymmetry of the response functions, but not of the giving-in time distributions. Two theoretical models of decision making are presented, which differ in the assumptions about memory constraints. In one case, all inter-reinforcement intervals are remembered but in the other, only the intervals with extreme values are remembered. Both models accommodate response rates as a function of trial time, but only the second is compatible with the observed departure decision. Our results are compatible with net rate maximization.
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Fetterman, J. G. (1996). Dimensions of stimulus complexity. J Exp Psychol Anim Behav Process, 22(1), 3–18.
Abstract: Animal learning research has increasingly used complex stimuli that approximate natural objects, events, and locations, a trend that has accompanied a resurgence of interest in the role of cognitive factors in learning. Accounts of complex stimulus control have focused mainly on cognitive mechanisms and largely ignored the contribution of stimulus information to perception and memory for complex events. It is argued here that research on animal learning stands to benefit from a more detailed consideration of the stimulus and that James Gibson's stimulus-centered theory of perception serves as a useful framework for analyses of complex stimuli. Several issues in the field of animal learning and cognition are considered from the Gibsonian perspective on stimuli, including the fundamental problem of defining the effective stimulus.
Keywords: Animals; *Behavior, Animal; Cognition; *Learning; Memory; Time Factors
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