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Neiworth, J. J., Hassett, J. M., & Sylvester, C. J. (2007). Face processing in humans and new world monkeys: the influence of experiential and ecological factors. Anim. Cogn., 10(2), 125–134.
Abstract: This study tests whether the face-processing system of humans and a nonhuman primate species share characteristics that would allow for early and quick processing of socially salient stimuli: a sensitivity toward conspecific faces, a sensitivity toward highly practiced face stimuli, and an ability to generalize changes in the face that do not suggest a new identity, such as a face differently oriented. The look rates by adult tamarins and humans toward conspecific and other primate faces were examined to determine if these characteristics are shared. A visual paired comparison (VPC) task presented subjects with either a human face, chimpanzee face, tamarin face, or an object as a sample, and then a pair containing the previous stimulus and a novel stimulus was presented. The stimuli were either presented all in an upright orientation, or all in an inverted orientation. The novel stimulus in the pair was either an orientation change of the same face/object or a new example of the same type of face/object, and the stimuli were shown either in an upright orientation or in an inverted orientation. Preference to novelty scores revealed that humans attended most to novel individual human faces, and this effect decreased significantly if the stimuli were inverted. Tamarins showed preferential looking toward novel orientations of previously seen tamarin faces in the upright orientation, but not in an inverted orientation. Similarly, their preference to look longer at novel tamarin and human faces within the pair was reduced significantly with inverted stimuli. The results confirmed prior findings in humans that novel human faces generate more attention in the upright than in the inverted orientation. The monkeys also attended more to faces of conspecifics, but showed an inversion effect to orientation change in tamarin faces and to identity changes in tamarin and human faces. The results indicate configural processing restricted to particular kinds of primate faces by a New World monkey species, with configural processing influenced by life experience (human faces and tamarin faces) and specialized to process orientation changes specific to conspecific faces.
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Matsuzawa, T. (2003). The Ai project: historical and ecological contexts. Anim. Cogn., 6(4), 199–211.
Abstract: This paper aims to review a long-term research project exploring the chimpanzee mind within historical and ecological contexts. The Ai project began in 1978 and was directly inspired by preceding ape-language studies conducted in Western countries. However, in contrast with the latter, it has focused on the perceptual and cognitive capabilities of chimpanzees rather than communicative skills between humans and chimpanzees. In the original setting, a single chimpanzee faced a computer-controlled apparatus and performed various kinds of matching-to-sample discrimination tasks. Questions regarding the chimpanzee mind can be traced back to Wolfgang Koehler's work in the early part of the 20th century. Yet, Japan has its unique natural and cultural background: it is home to an indigenous primate species, the Japanese snow monkey. This fact has contributed to the emergence of two previous projects in the wild led by the late Kinji Imanishi and his students. First, the Koshima monkey project began in 1948 and became famous for its discovery of the cultural propagation of sweet-potato washing behavior. Second, pioneering work in Africa, starting in 1958, aimed to study great apes in their natural habitat. Thanks to the influence of these intellectual ancestors, the present author also undertook the field study of chimpanzees in the wild, focusing on tool manufacture and use. This work has demonstrated the importance of social and ecological perspectives even for the study of the mind. Combining experimental approaches with a field setting, the Ai project continues to explore cognition and behavior in chimpanzees, while its focus has shifted from the study of a single subject toward that of the community as a whole.
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Burke, D., Cieplucha, C., Cass, J., Russell, F., & Fry, G. (2002). Win-shift and win-stay learning in the short-beaked echidna (Tachyglossus aculeatus). Anim. Cogn., 5(2), 79–84.
Abstract: Numerous previous investigators have explained species differences in spatial memory performance in terms of differences in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial memory performance of echidnas (or “spiny anteaters”) can be understood in terms of the spatio-temporal distribution of their prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas were better able to learn to avoid a previously rewarding location (to “win-shift”) than to learn to return to a previously rewarding location (to “win-stay”), at short retention intervals, but were unable to learn either of these strategies at retention intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval results do not.
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Janson, C., & Byrne, R. (2007). What wild primates know about resources: opening up the black box. Anim. Cogn., 10(3), 357–367.
Abstract: Abstract We present the theoretical and practical difficulties of inferring the cognitive processes involved in spatial movement decisions of primates and other animals based on studies of their foraging behavior in the wild. Because the possible cognitive processes involved in foraging are not known a priori for a given species, some observed spatial movements could be consistent with a large number of processes ranging from simple undirected search processes to strategic goal-oriented travel. Two basic approaches can help to reveal the cognitive processes: (1) experiments designed to test specific mechanisms; (2) comparison of observed movements with predicted ones based on models of hypothesized foraging modes (ideally, quantitative ones). We describe how these two approaches have been applied to evidence for spatial knowledge of resources in primates, and for various hypothesized goals of spatial decisions in primates, reviewing what is now established. We conclude with a synthesis emphasizing what kinds of spatial movement data on unmanipulated primate populations in the wild are most useful in deciphering goal-oriented processes from random processes. Basic to all of these is an estimate of the animals ability to detect resources during search. Given knowledge of the animals detection ability, there are several observable patterns of resource use incompatible with a pure search process. These patterns include increasing movement speed when approaching versus leaving a resource, increasingly directed movement toward more valuable resources, and directed travel to distant resources from many starting locations. Thus, it should be possible to assess and compare spatial cognition across a variety of primate species and thus trace its ecological and evolutionary correlates.
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Krueger, K., Farmer, K., & Heinze, J. (2014). The effects of age, rank and neophobia on social learning in horses. Anim. Cogn., 17(3), 645–655.
Abstract: Social learning is said to meet the demands of complex environments in which individuals compete over resources and co-operate to share resources. Horses (Equus caballus) were thought to lack social learning skills because they feed on homogenously distributed resources with few reasons for conflict. However, the horse’s social environment is complex, which raises the possibility that its capacity for social transfer of feeding behaviour has been underestimated. We conducted a social learning experiment using 30 socially kept horses of different ages. Five horses, one from each group, were chosen as demonstrators, and the remaining 25 horses were designated observers. Observers from each group were allowed to watch their group demonstrator opening a feeding apparatus. We found that young, low ranking, and more exploratory horses learned by observing older members of their own group, and the older the horse, the more slowly it appeared to learn. Social learning may be an adaptive specialisation to the social environment. Older animals may avoid the potential costs of acquiring complex and potentially disadvantageous feeding behaviours from younger group members. We argue that horses show social learning in the context of their social ecology, and that research procedures must take such contexts into account. Misconceptions about the horse’s sociality may have hampered earlier studies.
Keywords: Horse; Social learning; Sociality; Ecology; Social relationships
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Wittemyer, G., & Getz, W. M. (2007). Hierarchical dominance structure and social organization in African elephants, Loxodonta africana. Anim. Behav., 73(4), 671–681.
Abstract: According to the socioecological framework, transitivity (or linearity) in dominance relationships is related to competition over critical resources. When a population is structured into groups, the intensity of between- versus within-group competition influences the form and function of its social organization. Few studies have compared the type and relative intensity of competition at these two levels. African elephants have well-structured social relations, providing an exemplary system for such a study. We report on dominance hierarchies among free-ranging elephants and evaluate the factors that drive their socioecological structure to lie in a region of the three-dimensional nepotism/despotism/tolerance space rarely observed among social species; namely, where non-nepotistic, transitive dominance hierarchies within groups emerge despite kin-based philopatry and infrequent agonistic interactions over widely distributed resources. We found significant transitivity in dominance hierarchies between groups. Dominance relations among the matriarchs of different social groups were primarily age based, rather than driven by physical or group size, and group matriarch rank influenced the dominance relationships among nonmatriarchal females in the population. Our results suggest that between-group dominance relationships induce tolerance among group members, which in combination with high group relatedness, reduces the benefits of nepotism. We postulate that cognitive abilities and high risk of injury in contests enhance winner and loser effects, facilitating the formation of transitive dominance relationships, despite widely distributed resources over which infrequent competition occurs. The interplay of cognitive abilities, winner and loser effects, resource distribution, and within- and between-group dominance relationships may produce behaviour in other strongly social mammals that differs from that predicted by a superficial application of current socioecological models.
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Henson, S. M., Dennis, B., Hayward, J. L., Cushing, J. M., & Galusha, J. G. (2007). Predicting the dynamics of animal behaviour in field populations. Anim. Behav., 74(1), 103–110.
Abstract: Many species show considerable variation in behaviour among individuals. We show that some behaviours are largely deterministic and predictable with mathematical models. We propose a general differential equation model of behaviour in field populations and use the methodology to explain and predict the dynamics of sleep and colony attendance in seabirds as a function of environmental factors. Our model explained over half the variability in the data to which it was fitted, and it predicted the dynamics of an independent data set. Differential equation models may provide new approaches to the study of behaviour in animals and humans.
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Grafner, G., Zimmermann, H., Karge, E., Munch, J., Ribbeck, R., & Hiepe, T. (1976). [Incidence and damages inflicted by simuliid flies in the GDR district of Schwerin]. Angew Parasitol, 17(1), 2–6.
Abstract: Systematic faunal studies in the district Schwerin showed at the present time there are 3 more or less damage-biotopes existing in the districts of Perleberg, Ludwigslust and Parchim; 5 river sources can be considered as potential sources, 5 are temporary and 2 are ephemeral whilst in 3 further areas environmental influences such as effluent impairs the flow of the river and the developmental stages of Simuliidae were not observed.--The following species were found: Boophthora erythrocephala, Wilhelmia salopiensis, Wilhelmia equina, Odagmia ornata, Eusimulium aureum and Eusimulium lundstroemi.--The damage statistics covering the period 1966--1971 showed in the district of Schwerin, due to Simuliid attacks, 38 cattle died, 170 were seriously ill; in 1967 5 horses were seriously ill; in 1971, 3 pigs died and 27 were seriously ill.--The symptoms were manifested by pathological petechiae, scabs and oedema, also by insufficiency of the heart and circulatory system, diminished performance and growth disturbance. In severe cases heart and circulation failure occurred, paresis, coma and death followed.--The real economic significance of the Simuliid attacks rest with its strong and prolonged distrubance in young animals, as well as in pronounced irreparable diminished performance in diseased dairy cattle.
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Polley, L. (1986). Strongylid parasites of horses: experimental ecology of the free-living stages on the Canadian prairie. Am J Vet Res, 47(8), 1686–1693.
Abstract: Each month for a 1-year period (October through September), equine fecal masses containing eggs of strongylid nematodes were placed outdoors on small grass plots in Saskatchewan, Canada. Thereafter, feces and grass from the plots were sampled after intervals of 1 week or longer, and the strongylid eggs and larvae recovered were counted. These observations were made over a 2-year period. Development of eggs to infective larvae occurred in all experiments, except those established in October, December, and January. Infective larvae from experiments set up in April through September survived that winter. During the summer, there was a gradual build up of infective larvae in the fecal masses, which reached a peak in August and September and then decreased into the winter. These results are discussed in the context of the control of strongylid parasites of horses on the Canadian prairie and in other areas of the world with a similar climate and similar horse management practices.
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Scherer, W. F., Madalengoitia, J., Flores, W., & Acosta, M. (1975). Ecologic studies of Venezuelan encephalitis virus in Peru during 1970-1971. Am J Epidemiol, 101(4), 347–355.
Abstract: Venezuelan encephalitis (VE) virus has intermittently produced epidemics and equine epizootics on the dry Pacific coastal plain of Peru since at least the 1930's. However, evidence that the virus exists in the Amazon region of Peru to the east of the Andes mountains was not obtained until antibodies were found in human sera collected in 1965, and 10 strains of the virus were isolated in a forest near the city of Iquitos, Peru during February and March 1971. Eight strains came from mosquitoes and two from dead sentinel hamsters. Three hamsters exposed in forests near Iquitos developed VE virus antibodies suggesting that hamster-benign strains also exist there. Antibody tests of equine sera revealed no evidence that VE virus was actively cycling during the late 1950's or 1960's in southern coastal Peru, where equine epizootics had occurred in the 1930's and 1940's. In northern coastal Peru bordering Ecuador, antibodies were present in equine sera, presumably residual from the 1969 outbreak caused by subtype I virus, since neutralizing antibody titers were higher to subtype I virus than to subtypes III or IV. No VE virus was detected in this northern region during the dry season of 1970 by use of sentinel hamsters. The possibility is considered that VE epidemics and equine epizootics on the Pacific coast of Peru are caused by movements of virus in infected vertebrates traversing Andean passes or in infected vertebrates or mosquitoes carried in airplanes from the Amazon region.
Keywords: Animals; Antibodies, Viral; Cricetinae/immunology; Culicidae/microbiology; *Disease Vectors; Ecology; *Encephalitis Virus, Venezuelan Equine/immunology/isolation & purification; Encephalomyelitis, Equine/immunology/microbiology/transmission; Female; Hemagglutination Inhibition Tests; Horses/immunology; Humans; Neutralization Tests; Peru
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