Schlawe L,. (1980). Kritisches zur Nomenklatur und taxonomischen Beurteilung von Equus africanus. Equus, 2, 101–127.
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Seyfarth, R. M., Cheney, D. L., & Marler, P. (1980). Monkey responses to three different alarm calls: evidence of predator classification and semantic communication. Science, 210(4471), 801–803.
Abstract: Vervet monkeys give different alarm calls to different predators. Recordings of the alarms played back when predators were absent caused the monkeys to run into trees for leopard alarms, look up for eagle alarms, and look down for snake alarms. Adults call primarily to leopards, martial eagles, and pythons, but infants give leopard alarms to various mammals, eagle alarms to many birds, and snake alarms to various snakelike objects. Predator classification improves with age and experience.
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Jeffcott, L. B., & Dalin, G. (1980). Natural rigaidity of the horse's backbone. Equine Vet J, 12(3), 101–108.
Abstract: The functional anatomy of the thoracolumbar (TL) spine is considered in relation to the horse's ability to perform at speed and to jump. The morphological features quite clearly show the relative inflexibility of the equine back and this was confirmed by some experimental studies. Fresh post mortem specimens from 5 Thoroughbreds were used to estimate the limits of dorsoventral movement of the TL spine from mid-thoracic to the cranial lumbar (T10-L2). The individual spinous processes could be moved a mean 1.1-6.0 mm on maximum ventroflexion and 0.8-3.8 mm on dorsiflexion. The overall flexibility of the back was found to be 53.1 mm. Caudal to the mid-point of the back (T13) there was virtually no lateral or rotatory movement of the spine possible. The pathogenesis of some of the common causes of back trouble are discussed including the so-called vertebral subluxation and its treatment by chiropractic manipulation. From an anatomical viewpoint, this condition appears to be a misnomer and may simply be attributable to muscular imbalance leading to aspastic scoliosis.
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Keiper, R. R., & Keenan, M. A. (1980). Nocturnal activity patterns of feral horses. J. Mammal, 61, 116–118.
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Keiper Rr, K. M. (1980). Nocturnal activity patterns of feral ponies. J Mammal, 61, 116–118.
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Zentall, T. R., Hogan, D. E., Edwards, C. A., & Hearst, E. (1980). Oddity learning in the pigeon as a function of the number of incorrect alternatives. J Exp Psychol Anim Behav Process, 6(3), 278–299.
Abstract: Pigeons' rate of learning a two-color oddity task increased as a function of the number of incorrect alternatives from 2 to 24 in Experiments 1, 2, and 3. In general, pigeons that were transferred from many-incorrect-alternative to two-incorrect-alternative oddity performed better than controls, but considerably below baseline (Experiments 2 and 3). In Experiment 4, pigeons showed no unconditioned tendency to peck the odd stimulus among 24 incorect alternatives, when pecks were nondifferentially reinforced, and in Experiment 5, when this procedure was preceded by oddity training, a progressive drop in odd-stimulus pecking was found. In Experiment 6, pigeons exposed to a nine-stimulus array in which the odd stimulus appeared (a) in the center or (b) separate from the array learned faster than when the odd stimulus was at the edge. This outcome suggests ththe figure-ground relation between the odd stimulus and the incorrect alternatives plays a role in the facilitation produced by increasing the number of incorrect alternatives but that poor performance on the standard, three-alternative oddity task appears to be due to center-odd trials which provide a difficult size or number discrimination.
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Bunnell, B., & Perkins, M. (1980). Performance correlates of social behavior and organization: Social rank and complex problem solving in crab-eating macaques (M. fascicularis). Primates, 21(4), 515–523.
Abstract: Abstract Seventeen male crab-eating macaques, drawn from two captive troops, were tested on a series of complex problem solving tasks in a Wisconsin General Test Apparatus (wgta). The animals were trained on a series of 6-trial object quality learning set problems followed by a series of 10-trial object quality learning set problems. They were then given problems in which the correct stimulus object was reversed part way through the problem. After the animals reached criterion on this task, the reversal learning set was then extinguished. High ranking animals made more intraproblem errors than low ranking animals on the 6-trial problems, but there was no relationship between social status and the rapidity with which the object quality learning set was established. Animals that received overtraining on the 6-trial problems transferred their learning virtually intact to the 10-trial problems; however, high ranking animals without overtraining made more errors than low ranking animals. On reversal learning and reversal extinction, high ranking animals made more errors on critical trials, indicating that they formed and extinguished the reversal set more slowly than low ranking animals. Object quality sets, as measured by trial-2 performance, were not affected by the reversal conditions.
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Bunnell, B., Gore, W., & Perkins, M. (1980). Performance correlates of social behavior and organization: Social rank and reversal learning in crab-eating macaques (M. fascicularis). Primates, 21(3), 376–388.
Abstract: Abstract Seventeen male crab-eating macaques drawn from two captive troops, were tested on a brightness discrimination, reversal learning task. Fourteen of these animals completed ten reversals. It was found that the performance of the three highest ranking animals from each troop, taken together, was poorer than that of the lower ranking animals that were tested. The high ranking animals made more errors before reaching criterion on both initial learning and the reversal problems. Analysis of error patterns revealed that, while the high ranking animals had no more difficulty than the others in withholding their responses to the previously correct stimulus following reversals, they did not adopt the correct strategy as soon as the low ranking animals. The results have been interpreted in terms of a carry-over of a hypothetical factor or factors resulting from pressures created by the ongoing social dynamics involved in establishing and maintaining a given social rank at the time laboratory testing occurred.
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Clutton-Brock, T. H., & Harvey, P. H. (1980). Primates, brains and ecology. J. Zool. Lond., 190(3), 309–323.
Abstract: The paper examines systematic relationships among primates between brain size (relative to body size) and differences in ecology and social system. Marked differences in relative brain size exist between families. These are correlated with inter-family differences in body size and home range size. Variation in comparative brain size within families is related to diet (folivores have comparatively smaller brains than frugivores), home range size and possibly also to breeding system. The adaptive significance of these relationships is discussed.
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Salter Re, H. J. (1980). Range relationships of feral horses with wild ungulates and cattle in western Alberta. J Range Mgmt, 33, 266–271.
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