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Fehr, E., & Gachter, S. (2002). Altruistic punishment in humans. Nature, 415(6868), 137–140.
Abstract: Human cooperation is an evolutionary puzzle. Unlike other creatures, people frequently cooperate with genetically unrelated strangers, often in large groups, with people they will never meet again, and when reputation gains are small or absent. These patterns of cooperation cannot be explained by the nepotistic motives associated with the evolutionary theory of kin selection and the selfish motives associated with signalling theory or the theory of reciprocal altruism. Here we show experimentally that the altruistic punishment of defectors is a key motive for the explanation of cooperation. Altruistic punishment means that individuals punish, although the punishment is costly for them and yields no material gain. We show that cooperation flourishes if altruistic punishment is possible, and breaks down if it is ruled out. The evidence indicates that negative emotions towards defectors are the proximate mechanism behind altruistic punishment. These results suggest that future study of the evolution of human cooperation should include a strong focus on explaining altruistic punishment.
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Fischer, J., Hammerschmidt, K., Cheney, D. L., & Seyfarth, R. M. (2002). Acoustic features of male baboon loud calls: influences of context, age, and individuality. J Acoust Soc Am, 111(3), 1465–1474.
Abstract: The acoustic structure of loud calls (“wahoos”) recorded from free-ranging male baboons (Papio cynocephalus ursinus) in the Moremi Game Reserve, Botswana, was examined for differences between and within contexts, using calls given in response to predators (alarm wahoos), during male contests (contest wahoos), and when a male had become separated from the group (contact wahoos). Calls were recorded from adolescent, subadult, and adult males. In addition, male alarm calls were compared with those recorded from females. Despite their superficial acoustic similarity, the analysis revealed a number of significant differences between alarm, contest, and contact wahoos. Contest wahoos are given at a much higher rate, exhibit lower frequency characteristics, have a longer “hoo” duration, and a relatively louder “hoo” portion than alarm wahoos. Contact wahoos are acoustically similar to contest wahoos, but are given at a much lower rate. Both alarm and contest wahoos also exhibit significant differences among individuals. Some of the acoustic features that vary in relation to age and sex presumably reflect differences in body size, whereas others are possibly related to male stamina and endurance. The finding that calls serving markedly different functions constitute variants of the same general call type suggests that the vocal production in nonhuman primates is evolutionarily constrained.
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Fisher, D. O., Blomberg, S. P., & Owens, I. P. F. (2002). Convergent Maternal Care Strategies In Ungulates And Macropods. Evolution, 56(1), 167–176.
Abstract: Mammals show extensive interspecific variation in the form of maternal care. Among ungulates, there is a dichotomy between species in which offspring follow the mother (“following” strategy) versus species in which offspring remain concealed (“hiding” strategy). Here we reveal that the same dichotomy exists among macropods (kangaroos, wallabies and allies). We test three traditional adaptive explanations and one new life history hypothesis, and find very similar patterns among both ungulates and macropods. The three traditional explanations that we tested were that a “following” strategy is associated with (1) open habitat, (2) large mothers, and (3) gregariousness. Our new life-history hypothesis is that a “following strategy” is associated with delayed weaning, and thus with the “slow” end of the slow-fast mammalian life-history continuum, because offspring devote resources to locomotion rather than rapid growth. Our comparative test strongly supports the habitat structure hypothesis and provides some support for this new delayed weaning hypothesis for both ungulates and macropods. We propose that sedentary young in closed habitats benefit energetically by having milk brought to them. In open habitats, predation pressure will select against hiding. Followers will suffer slower growth to independence. Taken together, therefore, our results provide the first quantitative evidence that macropods and ungulates are convergent with respect to interspecific variation in maternal care strategy. In both clades, differences between species in the form of parental care are due to a similar interaction between habitat, social behavior, and life history. Corresponding Editor: B. Crespi
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Flannigan, G., & Stookey, J. M. (2002). Day-time time budgets of pregnant mares housed in tie stalls: a comparison of draft versus light mares. Appl. Anim. Behav. Sci., 78(2-4), 125–143.
Abstract: Day-time (08.30-05.30 h) time budgets were generated from 55 light and 55 draft late pregnancy mares housed in tie stalls from ten pregnant mares' urine (PMU) farms using continuous video recording. Equal numbers of light and draft mares were filmed on each farm during the months of February and early March. The actions recorded included eating, drinking, resting (standing and recumbent), standing active, and interactions between horses (aggressive and non-aggressive). In addition, the presence and duration of stereotypic behaviours such as cribbing, head bobbing, weaving, and wood/bar chewing were recorded. Light mares spent significantly more time feeding and significantly less time standing active and standing resting (P<0.05, Rank Sum Two Sample Test). However, the time budget of both groups fell within the range of previously published activity budgets of feral horses. Therefore, the differences noted may not be clinically relevant. Three light and two draft mares performed repetitive behaviours at a level that is considered stereotypic (at >5% of their daily time budget). There was no significant difference in the number of horses performing stereotypies between light and draft mares. When the time budgets of both light and draft mares who performed stereotypies were pooled, the activities did not differ significantly from their counterparts who did not perform stereotypies. Because of the overall low prevalence of stereotypies and the fact that time budgets were similar to free-range horses, we believe that the management practice of keeping large numbers of pregnant mares in tie stalls is rational and that the welfare of mares is sound. Furthermore, we did not see a behavioural justification for a bias in the weight class of horses used within this management system.
Keywords: Horse; Time budget; Stereotypies; Housing
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Fremouw, T., Herbranson, W. T., & Shimp, C. P. (2002). Dynamic shifts of pigeon local/global attention. Anim. Cogn., 5(4), 233–243.
Abstract: It has previously been shown that pigeons can shift attention between parts and wholes of complex stimuli composed of larger, “global” characters constructed from smaller, “local” characters. The base-rate procedure used biased target level within any condition at either the local or global level; targets were more likely at one level than at the other. Biasing of target level in this manner demonstrated shifts of local/global attention over a time span consisting of several days with a fixed base rate. Experiment 1 examined the possibility that pigeons can shift attention between local and global levels of perceptual analysis in seconds rather than days. The experiment used priming cues the color of which predicted on a trial-by-trial basis targets at different perceptual levels. The results confirmed that pigeons, like humans, can display highly dynamic stimulus-driven shifts of local/global attention. Experiment 2 changed spatial relations between features of priming cues and features of targets within a task otherwise similar to that used in experiment 1. It was predicted that this change in cues might affect asymmetry but not the occurrence of a priming effect. A priming effect was again obtained, thereby providing generality to the claim that pigeons can learn that trial-by-trial primes predict targets at different levels of perceptual analysis. Pigeons can display perceptual, stimulus-driven priming of a highly dynamic nature.
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Fuentes, A., Malone, N., Sanz, C., Matheson, M., & Vaughan, L. (2002). Conflict and post-conflict behavior in a small group of chimpanzees. Primates, 43(3), 223–235.
Abstract: Chimpanzee research plays a central role in the discussions of conflict negotiation. Reconciliation, or the attraction and affiliation of former opponents following conflict, has been proposed as a central element of conflict negotiation in chimpanzees and various other taxa. In an attempt to expand the database of chimpanzee conflict resolution, conflict and post-conflict behavior were recorded for a small group of socially housed chimpanzees at the Chimpanzee and Human Communication Institute, at Central Washington University. Data were collected over six 6-week periods between 1997 and 2000, for a total of 840 hours of observation, resulting in a substantial post-conflict (PC) and matched control (MC) data set. The data demonstrate this group's tendencies to maintain visual contact and closer proximity after conflicts. Dyadic corrected conciliatory tendencies ranged between 0 – 37.5% and averaged 17.25% across all dyads. Individual corrected conciliatory tendencies ranged between 5.8 and 32%. The results of this study combined with recent publications on captive and free-ranging chimpanzee post-conflict behavior suggest that variation in post-conflict behavior may be important to our understanding of chimpanzee conflict negotiation, and may also have implications for the design and management of captive chimpanzee enclosures and social groups, respectively.
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Fujita, K., Kuroshima, H., & Masuda, T. (2002). Do tufted capuchin monkeys (Cebus apella) spontaneously deceive opponents? A preliminary analysis of an experimental food-competition contest between monkeys. Anim. Cogn., 5(1), 19–25.
Abstract: A new laboratory procedure which allows the study of deceptive behavior in nonhuman primates is described. Pairs of tufted capuchin monkeys faced each other in a food-competition contest. Two feeder boxes were placed between the monkeys. A piece of food was placed in one of the boxes. The subordinate individual was able to see the food and to open the box to obtain the bait. A dominant male was unable to see the food or to open the box but was able to take the food once the box was opened by the subordinate. In experiment 1, two of four subordinate monkeys spontaneously started to open the unbaited box first with increasing frequency. Experiment 2 confirmed that this “deceptive” act was not due to a drop in the rate of reinforcement caused by the usurping dominant male, under the situation in which food sometimes automatically dropped from the opened box. In experiment 3, two subordinate monkeys were rerun in the same situation as experiment 1. One of them showed some recovery of the “deceptive” act but the other did not; instead the latter tended to position himself on the side where there was no food before he started to open the box. Although the results do not clearly indicate spontaneous deception, we suggest that operationally defined spontaneous deceptive behaviors in monkeys can be analyzed with experimental procedures such as those used here.
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Funk, M. S. (2002). Problem solving skills in young yellow-crowned parakeets (Cyanoramphus auriceps). Anim. Cogn., 5(3), 167–176.
Abstract: Despite the long divergent evolutionary history of birds and mammals, early avian and primate cognitive development have many convergent features. Some of these features were investigated with a series of tasks designed to assess human infant development. The tasks were presented to young parakeets to assess their means-end problem solving abilities. Examples of these early skills are: attaining and playing with objects, retrieving rewards through use of a stick or rake, or by pulling in rewards on supports or on the ends of strings. Twelve such tasks were presented to 11 young yellow-crowned parakeets ( Cyanoramphus auriceps) to investigate their natural abilities; there was no attempt to train them to do those tasks that they did not spontaneously perform. Six of the birds were parent-raised and five were hand-raised. The birds completed 9 of the 12 tasks, demonstrating all the Piagetian sensorimotor circular reactions, but they failed to hand-watch (“claw-watch”), to stack objects, or to fill a container. Their ordinality on the tasks differed from that of human infants in that locomotion to obtain objects occurred earlier in the avian sequence of development and the mid-level tasks were performed by the two groups of avian subjects in a mixed order perhaps indicating that these abilities may not emerge in any particular order for these birds as they supposedly do for human infants. The hand-raised group needed fewer sessions to complete these means-end tasks.
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Garamszegi, L. Z., Møller, A. P., & Erritzøe, J. (2002). Coevolving avian eye size and brain size in relation to prey capture and nocturnality. Proc Roy Soc Lond B Biol Sci, 269(1494), 961–967.
Abstract: Behavioural adaptation to ecological conditions can lead to brain size evolution. Structures involved in behavioural visual information processing are expected to coevolve with enlargement of the brain. Because birds are mainly vision–oriented animals, we tested the predictions that adaptation to different foraging constraints can result in eye size evolution, and that species with large eyes have evolved large brains to cope with the increased amount of visual input. Using a comparative approach, we investigated the relationship between eye size and brain size, and the effect of prey capture technique and nocturnality on these traits. After controlling for allometric effects, there was a significant, positive correlation between relative brain size and relative eye size. Variation in relative eye and brain size were significantly and positively related to prey capture technique and nocturnality when a potentially confounding variable, aquatic feeding, was controlled statistically in multiple regression of independent linear contrasts. Applying a less robust, brunching approach, these patterns also emerged, with the exception that relative brain size did not vary with prey capture technique. Our findings suggest that relative eye size and brain size have coevolved in birds in response to nocturnal activity and, at least partly, to capture of mobile prey.
Keywords: adaptation; behaviour; brain size; coevolution; eye size; vision
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Gazzola, A., Avanzinelli, E., Mauri, L., Scandura, M., & Apollonio, M. (2002). Temporal changes of howling in south European wolf packs. Ital J Zool, 69.
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