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Dugatkin, L. A., & Godin, G. J. (1992). Predator inspection, shoaling and foraging under predation hazard in the Trinidadian guppy,Poecilia reticulata. Environmental Biology of Fishes, 34(3), 265–276.
Abstract: Guppies,Poecilia reticulata, living in stream pools in Trinidad, West Indies, approached a potential fish predator (a cichlid fish model) in a tentative, saltatory manner, mainly as singletons or in pairs. Such behavior is referred to as predator inspection behavior. Inspectors approached the trunk and tail of the predator model more frequently, more closely and in larger groups than they approached the predator's head, which is presumably the most dangerous area around the predator. However, guppies were not observed in significantly larger shoals in the stream when the predator model was present. In a stream enclosure, guppies inspected the predator model more frequently when it was stationary compared to when it was moving, and made closer inspections to the posterior regions of the predator than to its head. Therefore, the guppies apparently regarded the predator model as a potential threat and modified their behavior accordingly when inspecting it. Guppies exhibited a lower feeding rate in the presence of the predator, suggesting a trade-off between foraging gains and safety against predation. Our results further suggest that predator inspection behavior may account for some of this reduction in foraging. These findings are discussed in the context of the benefits and costs of predator inspection behavior.
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Pruett-Jones, S. (1992). Independent Versus Nonindependent Mate Choice: Do Females Copy Each Other? Am Nat, 140(6), 1000–1009.
Abstract: There is increasing evidence from both observational and experimental studies that females may copy each other's mating decisions. Female copying can be defined as a type of nonindependent choice in which the probability that a female chooses a given male increases if other females have chosen that male and decreases if they have not. The important characteristic of copying behavior that separates it from other similar processes is that the change in the probability of choice is strictly because of the actions of other females and not the consequences of those actions (e.g., a male's behavior changing as a result of successful matings). A gametheory model suggests that the adaptive significance of female copying may depend primarily on the ratio of the costs to the benefits of active mate choice. Copying behavior, and more generally conspecific cueing, may be important in many behavioral processes beyond mate choice.
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Smith-Funk, E. D., & Crowell-Davis, S. L. (1992). Maternal behavior of draft mares (Equus caballus) with mule foals (Equus asinus x Equus caballus). Appl. Anim. Behav. Sci., 33(2-3), 93–119.
Abstract: Draft mares and their mule foals were observed from the day of birth to Week 17 of each foal's life. The rate of nursing was recorded and the duration of nursing activity to the nearest second. The rate at which foals engaged in nursing activity varied at each age. The duration of nursing bouts varied slightly as the foals matured. Aggression was recorded during both nursing and non-nursing activity for both the mares and foals. Maternal aggression was highest during nursing activity, especially during the pre-nurse nuzzling period. Maternal aggression increased as the foals matured. Mother-directed foal aggression was primarily in response to maternal aggression. Spatial relationships between each focal dyad were recorded when the foals were upright, not nursing and when they were recumbent. Spatial relationships differed based on the foal's state. The activity in which the mare engaged while her foal was recumbent was recorded. The movements of the mares were also recorded during foal recumbency. Mares approached or maintained their distance from their recumbent foal more than they left their recumbent foal in all weeks of the study, except Week 2.
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Dvoinos, G. M., Kharchenko, V. A., & Zviagnitsova, N. S. (1992). The characteristics of the helminth community in the Turkmen kulan (Equus hemionus). Parazitologiia, 26(3), 246–251.
Abstract: The helminth fauna of 24 kulans from Askaniya-Nova and Badkhyz was studied. 42 species of helminths were found, 34 of which belong to strongylids. The helminth species composition of kulan is similar to that of other species of horses. This is a result of an intensive parasite exchange in the historical past when numerous populations of different Equidae species made long seasonal migrations over steppe inter-river lands of Asia and grazed for some time on common pastures.
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Mills, M. G. L., & Shenk, M. G. L. (1992). Predator--Prey Relationships: The Impact of Lion Predation on Wildebeest and Zebra Populations. T. J. Anim. Ecol., 61(3), 693–702.
Abstract: 1. The role of lion Panthera leo predation in the dynamics of blue wildebeest Connochaetes taurinus and zebra Equus burchelli populations was investigated through simulation models. The data used in the models were from intensive observations over 4 years in the south-east of the Kruger National Park. 2. Population estimates of wildebeest and zebra were made from aerial surveys, sex and age ratios from ground counts. Lion numbers were determined from observations of marked and radio-collared animals. Predation was studied by following lions for continuous periods of up to 336 h. 3. Two models were constructed. Model 1 ascertained the number of killing lions (adult females) that could be supported by each prey population while remaining stable. A single model was constructed for the sedentary wildebeest population. A summer and winter model was constructed for the semi-migratory zebra population. The sensitivity of the parameters in the model was tested by changing their value by 10%. In model 2, the kill age structure for each species was changed to determine the number of killing lions the altered prey selection parameters could support. 4. There was no difference in the vulnerability of either species to predation. Zebra foals (<1 year) were killed more frequently than expected. No selection for sex or by season could be found for either species. 5. Model 1 predicted that the wildebeest population stabilizes with 7.7 killing lions, close to the number in the study area. The winter zebra population stabilizes with 6.8 killing lions and the summer zebra population with 19.4. Manipulation of kill rate followed by adult fecundity rate had the greatest effect on population size of both species. In model 2, wildebeest predation was made selective towards calves and zebra predation was made non-selective for sex and age. With these parameters the wildebeest population stabilizes with 10.7 killing lions and the zebra population with 5.4 in winter and 15.1 in summer. 6. The models suggest that lion predation affected wildebeest more severely than zebra during the study. This was through the way in which lions selected their prey, and because of the sedentary behaviour of the wildebeest, as opposed to the semi-migratory behaviour of the zebra.
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Munthali, S. M., & Banda, H. M. (1992). Distribution and abundance of the common ungulates of Nyika National Park. Afr. J. Ecol, 30, 203–212.
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Novacek, M. J. (1992). Mammalian phylogeny: shaking the tree. Nature, 356(6365), 121–125.
Abstract: Recent palaeontological discoveries and the correspondence between molecular and morphological results provide fresh insight on the deep structure of mammalian phylogeny. This new wave of research, however, has yet to resolve some important issues.
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Poysa, H. (1992). Group Foraging in Patchy Environments: The Importance of Coarse-Level Local Enhancement. Ornis[ Scand[, 23(2), 159–166.
Abstract: Local enhancement is one way individuals may realize foraging advantages from grouping. A distinction between fine-level and coarse-level local enhancement is made, the latter often being neglected in theoretical research on group foraging. In the former case, an individual has a higher feeding rate as a member of a group because individuals copy other group members' foraging, whereas in the latter, groups simply attract other individuals to patches where food is particularly abundant and copying does not occur within the group. Coarse-level local enhancement may decrease the time needed to find profitable feeding patches in spatially and temporally variable environments. A review of the empirical literature indicated that coarse-level local enhancement is typical in bird species foraging in open habitats and in large groups with relatively little competition between group members whereas the opposite attributes fit the species for which fine-level local enhancement had been documented. Furthermore, species in which coarse-level local enhancement prevails usually forage in temporary groups. However, coarse-level and fine-level local enhancement are not necessarily mutually exclusive, but which one is more important in a particular case may be habitat-dependent.
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Schmidt, D. (1992). Information Resources in Animal Behavior. Science & Technology Libraries, 12(1), 69–83.
Abstract: The study of animal behavior has been around for many years, but it is divided into several fields which often do not communicate well. These fields of study include (but are not limited to) comparative psychology, ethology, behavioral ecology, and sociobiology. Comparative psychology is more isolated than the other three fields, which share a common biological/evolutionary background. This paper gives a brief background of the four main fields of animal behavior research, along with a list of sources, both specialized and interdisciplinary.
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Wall, D. L., Topliff, D. R., Freeman, D. W., Wagner, D. G., Breazile, J. W., & Stutz, W. A. (1992). Effect of dietary cation-anion balance on urinary mineral excretion in exercised horses. Journal of Equine Veterinary Science, 12(3), 168–171.
Abstract: Summary Four mares and four geldings of Quarter Horse and Thoroughbred breeding were used in two simultaneous 4x4 Latin square experiments to study the effects of dietary cation-anion balance (DCAB), defined as meq ((Na+K)-C1)/kg dry matter, on urinary pH and mineral excretion in exercised horses. Diets consisted of a pelleted concentrate of corn, soybean meal and cottonseed hulls fed with bermudagrass hay. Treatments with DCAB of +5 (Low, L), +107 (Medium Low, ML), +201 (Medium High, MH) and +327 (High, H), meq ((Na+K)-Cl)/kg dry matter were formed by supplementing diet L with calcium chloride and ammonium chloride, diet ML with calcium chloride and diet H with sodium bicarbonate and potassium citrate (Table 1). Diet MH was not supplemented and served as the control treatment. Horses were conditioned aerobically for 6 weeks using long, slow, distance (LSD) workouts. During the experimental periods, horses were subjected to a combined exercise regimen alternating LSD with an interval-training protocol 6 days/week. There was a significant (P<.01) treatment effect on urine pH; least squares means for L, ML, MH and H were 6.73, 7.17, 7.38, and 7.92. Horses consuming diet L excreted more calcium in the urine (P<.05) than those consuming MH or H. Least squares means for daily urine calcium excretion tended to be linear across treatments and ranged from 19.66 g/day for diet L to 9.12 g/day for diet H. Urinary chloride excretion was higher (P<.05) for L than for MH or H. Horses fed diet H excreted more sodium (P<.05) in urine than horses fed the other diets. Lowering DCAB, increases urinary calcium loss; depending on the level of calcium intake, this could lead to negative calcium balance in exercising horses.
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