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Katherine Faust, & John Skvoretz. (2002). Comparing Networks Across Space and Time, Size and Species. Socio Meth, 32(1), 267–299.
Abstract: We describe and illustrate methodology for comparing networks from diverse settings. Our empirical base consists of 42 networks from four kinds of species (humans, nonhuman primates, nonprimate mammals, and birds) and covering distinct types of relations such as influence, grooming, and agonistic encounters. The general problem is to determine whether networks are similarly structured despite their surface differences. The methodology we propose is generally applicable to the characterization and comparison of network2013level social structures across multiple settings, such as different organizations, communities, or social groups, and to the examination of sources of variability in network structure. We first fit a p* model (Wasserman and Pattison 1996) to each network to obtain estimates for effects of six structural properties on the probability of the graph. We then calculate predicted tie probabilities for each network, using both its own parameter estimates and the estimates from every other network in the collection. Comparison is based on the similarity between sets of predicted tie probabilities. We then use correspondence analysis to represent the similarities among all 42 networks and interpret the resulting configuration using information about the species and relations involved. Results show that similarities among the networks are due more to the kind of relation than to the kind of animal.
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Akins, C. K., Klein, E. D., & Zentall, T. R. (2002). Imitative learning in Japanese quail (Coturnix japonica) using the bidirectional control procedure. Anim Learn Behav, 30(3), 275–281.
Abstract: In the bidirectional control procedure, observers are exposed to a conspecific demonstrator responding to a manipulandum in one of two directions (e.g., left vs. right). This procedure controls for socially mediated effects (the mere presence of a conspecific) and stimulus enhancement (attention drawn to a manipulandum by its movement), and it has the added advantage of being symmetrical (the two different responses are similar in topography). Imitative learning is demonstrated when the observers make the response in the direction that they observed it being made. Recently, however, it has been suggested that when such evidence is found with a predominantly olfactory animal, such as the rat, it may result artifactually from odor cues left on one side of the manipulandum by the demonstrator. In the present experiment, we found that Japanese quail, for which odor cues are not likely to play a role, also showed significant correspondence between the direction in which the demonstrator and the observer push a screen to gain access to reward. Furthermore, control quail that observed the screen move, when the movement of the screen was not produced by the demonstrator, did not show similar correspondence between the direction of screen movement observed and that performed by the observer. Thus, with the appropriate control, the bidirectional procedure appears to be useful for studying imitation in avian species.
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Dorrance, B. R., & Zentall, T. R. (2002). Imitation of conditional discriminations in pigeons (Columba livia). J Comp Psychol, 116(3), 277–285.
Abstract: In the present experiments, the 2-action method was used to determine whether pigeons could learn to imitate a conditional discrimination. Demonstrator pigeons (Columba livia) stepped on a treadle in the presence of 1 light and pecked at the treadle in the presence of another light. Demonstration did not seem to affect acquisition of the conditional discrimination (Experiment 1) but did facilitate its reversal of the conditional discrimination (Experiments 2 and 3). The results suggest that pigeons are not only able to learn a specific behavior by observing another pigeon, but they can also learn under which circumstances to perform that behavior. The results have implications for proposed mechanisms of imitation in animals.
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Hemelrijk, C. K. (2002). Self-Organization and Natural Selection in the Evolution of Complex Despotic Societies. Biol Bull, 202(3), 283–288.
Abstract: Differences between related species are usually explained as separate adaptations produced by individual selection. I discuss in this paper how related species, which differ in many respects, may evolve by a combination of individual selection, self-organization, and group-selection, requiring an evolutionary adaptation of only a single trait. In line with the supposed evolution of despotic species of macaques, we take as a starting point an ancestral species that is egalitarian and mildly aggressive. We suppose it to live in an environment with abundant food and we put the case that, if food becomes scarce and more clumped, natural selection at the level of the individual will favor individuals with a more intense aggression (implying, for instance, biting and fierce fighting). Using an individual-centered model, called DomWorld, I show what happens when the intensity of aggression increases. In DomWorld, group life is represented by artificial individuals that live in a homogeneous world. Individuals are extremely simple: all they do is flock together and, upon meeting one another, they may perform dominance interactions in which the effects of winning and losing are self-reinforcing. When the intensity of aggression in the model is increased, a complex feedback between the hierarchy and spatial structure results; via self-organization, this feedback causes the egalitarian society to change into a despotic one. The many differences between the two types of artificial society closely correspond to those between despotic and egalitarian macaques in the real world. Given that, in the model, the organization changes as a side effect of the change of one single trait proper to an egalitarian society, in the real world a despotic society may also have arisen as a side effect of the mutation of a single trait of an egalitarian species. If groups with different intensities of aggression evolve in this way, they will also have different gradients of hierarchy. When food is scarce, groups with the steepest hierarchy may have the best chance to survive, because at least a small number of individuals in such a group may succeed in producing offspring, whereas in egalitarian societies every individual is at risk of being insufficiently fed to reproduce. Therefore, intrademic group selection (selection within an interbreeding group) may have contributed to the evolution of despotic societies. N1 -
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Visser, E. K., van Reenen, C. G., van der Werf, J. T. N., Schilder, M. B. H., Knaap, J. H., Barneveld, A., et al. (2002). Heart rate and heart rate variability during a novel object test and a handling test in young horses. Physiol. Behav., 76(2), 289–296.
Abstract: Forty-one Dutch Warmblood immature horses were used in a study to quantify temperamental traits on the basis of heart rate (HR) and heart rate variability (HRV) measures. Half of the horses received additional training from the age of 5 months onwards; the other half did not. Horses were tested at 9, 10, 21 and 22 months of age in a novel object and a handling test. During the tests, mean HR and two heart variability indices, e.g. standard deviation of beat-to-beat intervals (SDRR) and root mean square of successive beat-to-beat differences (rMSSD), were calculated and expressed as response values to baseline measures. In both tests, horses showed at all ages a significant increase in mean HR and decrease in HRV measures, which suggests a marked shift of the balance of the autonomic nervous system towards a sympathetic dominance. In the novel object test, this shift was more pronounced in horses that had not been trained. Furthermore, statistical analysis showed that the increase in mean HR could not be entirely explained by the physical activity. The additional increase in HR, the nonmotor HR, was more pronounced in the untrained horses compared to the trained. Hence, it is suggested that this nonmotor HR might be due to the level of emotionality. HR variables showed consistency between years, as well as within the second year. These tests bring about a HR response in horses, part of which may indicate a higher level of emotionality; and horses show individual consistency of these HR variables over ages. Therefore, it is concluded that mean HR and HRV measures used with these tests quantify certain aspects of a horse's temperament.
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Heleski, C. R., Shelle, A. C., Nielsen, B. D., & Zanella, A. J. (2002). Influence of housing on weanling horse behavior and subsequent welfare. Appl. Anim. Behav. Sci., 78(2-4), 291–302.
Abstract: Weaning foals marks a stressful event in horses' lives. Limited research exists regarding different housing methods post-weaning and the long-term implications on horse behavior and welfare. The purpose of this study was to monitor behavior and physiological stress markers in horses weaned individually in solid partition box stalls versus horses weaned in small groups and housed in paddocks. Both treatment groups underwent maternal deprivation stress, but the stalled weanlings had the additive effects of social isolation which prevented them from performing social behaviors. Quarter Horse weanlings from the Michigan State University, Merillat Equine Center, average age 4.5 months, were weaned in 13.4 m2 box stalls (n=6) or in groups of three in a 992 m2 paddock, which had very limited grazing forage and an open shelter available (n=6). Subjects were fed concentrate and hay to National Research Council recommendations. A time budget for 31 observed behaviors was developed. Behavioral observations were made 2 days per week, approximately 6 h per day, for the duration of the 56 days study. Instantaneous samples were recorded every 5 min on each observation day, with equal division between the two treatment groups (n=35 scans per horse per observation day). Focal data were recorded continuously between scans to provide a more detailed ethogram. On each observation day, fecal samples were collected to measure 11,17-dioxoandrostanes, an indicator of glucocorticoid metabolite concentration. Regarding the fecal 11,17-dioxoandrostanes, there was no discernible treatment difference either immediately post-weaning or at the conclusion of the 56 days study. Interestingly, all 12 weanlings showed a 4 week post-weaning increase in 11,17-dioxoandrostanes. The reason for this peak was unclear. Behavioral observations demonstrated a significantly different time budget in paddock-housed weanlings than in stall-housed weanlings (P<0.0001). Paddock-housed weanlings displayed a time budget more like a feral horse time budget, showing more time spent moving and less time spent lying. Paddock-housed weanlings, who had the option of selectively engaging in a broader range of behaviors, showed strong motivation to graze and be near conspecifics. Stalled weanlings spent significantly more time engaged in aberrant behaviors: licking or chewing the stall/shed wall, kicking at the stall/shed wall, pawing, and bucking/rearing bouts (P<0.03). Based on the variety of behaviors shown, the ability to engage in strongly preferred behaviors, and freedom from aberrant behavior, we conclude that the paddock-reared, group-housed weanlings had better welfare. However, there was insufficient evidence to conclude that the stalled weanlings had poor welfare.
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Parrish, J. K., Viscido, S. V., & Grunbaum, D. (2002). Self-Organized Fish Schools: An Examination of Emergent Properties. Biol Bull, 202(3), 296–305.
Abstract: Heterogeneous, “aggregated” patterns in the spatial distributions of individuals are almost universal across living organisms, from bacteria to higher vertebrates. Whereas specific features of aggregations are often visually striking to human eyes, a heuristic analysis based on human vision is usually not sufficient to answer fundamental questions about how and why organisms aggregate. What are the individual-level behavioral traits that give rise to these features? When qualitatively similar spatial patterns arise from purely physical mechanisms, are these patterns in organisms biologically significant, or are they simply epiphenomena that are likely characteristics of any set of interacting autonomous individuals? If specific features of spatial aggregations do confer advantages or disadvantages in the fitness of group members, how has evolution operated to shape individual behavior in balancing costs and benefits at the individual and group levels? Mathematical models of social behaviors such as schooling in fishes provide a promising avenue to address some of these questions. However, the literature on schooling models has lacked a common framework to objectively and quantitatively characterize relationships between individual-level behaviors and group-level patterns. In this paper, we briefly survey similarities and differences in behavioral algorithms and aggregation statistics among existing schooling models. We present preliminary results of our efforts to develop a modeling framework that synthesizes much of this previous work, and to identify relationships between behavioral parameters and group-level statistics. N1 -
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Hauser MD, Pearson H, & Seelig D. (2002). Ontogeny of tool use in cottontop tamarins, Saguinus oedipus: innate recognition of functionally relevant features. Anim. Behav., 64, 299.
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Santamaria, S., Back, W., van Weeren, P. R., Knaap, J., & Barneveld, A. (2002). Jumping characteristics of naive foals: lead changes and description of temporal and linear parameters. Equine Vet J Suppl, (34), 302–307.
Abstract: The selection of foals as future showjumpers remains a subjective process based on qualitative parameters; and hence, frequently suffers from disparity in the criteria used by experts in the field. A detailed biomechanical description of foals while jumping would be most helpful in providing a better basis for the accurate assessment of their future athletic ability. The Qualisys Pro Reflex system was used to capture 3-dimensional kinematics of 41 Dutch Warmblood foals age 6 months free jumping a vertical fence, preceded by a cross pole fence. The left lead was the most preferred lead for both the fore- and hindlimbs, from the landing following the cross poles to the first move-off stride after clearing the vertical fence. The foals displayed a high incidence of rotary gallop during both the jump stride (divided into take-off, jump suspension and landing) and the first move-off stride, while change of lead was frequently observed during jump suspension. At the take-off side of the fence, the trailing forelimb in the last approach stride was placed furthest from the fence, whereas the trailing hindlimb at take-off was placed closest (P<0.05). At the landing side, the trailing forelimb was the closest and the leading hindlimb of the move-off stride 1 was the furthest (P<0.05). The trailing forelimb in the approach stride 1 had a significantly longer stance phase duration than the leading forelimb. At landing, the leading forelimb stance phase lasted longer than that of the trailing forelimb (P<0.05). The hindlimbs did not differ in their stance phase duration at take-off. The height reached by the hooves above the fence top was significantly greater in the hind limbs (P<0.05). In addition, the hindlimbs (97.1 +/- 2.6%) shortened more than the forelimbs (92.6 +/- 5.7%) (P<0.05). It is concluded that the overall jumping technique of foals is similar to that reported in literature for mature horses. If the patterns are consistent throughout the rearing period, the quantitative analysis of the kinematics of free jumping foals may provide a valid quantitative basis for early selection.
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Simpson, B. S. (2002). Neonatal foal handling. Appl. Anim. Behav. Sci., 78(2-4), 303–317.
Abstract: Recent interest has focused on the advantage of intensively handling young foals as a means of producing more tractable horses, accustomed to humans and receptive to training. To date, the effect of this intensive handling, dubbed “imprint training” in the popular literature, has not been tested. The present study compares seven foals handled intensively as neonates with eight untreated controls. The handling protocol started from 2-8 h after birth and continued daily for a total of 5 days. The protocol consisted of a series of stimuli and experiences that were each repeated until the foal no longer resisted or reacted negatively. Subsequently, foals were tested before weaning, at 4 months of age. Results indicated that handled foals (HF) ranked higher than control foals (CF) in subjective ratings of calmness (*P<0.0117) and friendliness (*P<0.0001) and in several specific handling tasks (venipuncture *P<0.0220; placing in stock *P<0.0128). Although, in approach tests all foals but one allowed approach of a person to 4 m, significantly more HF approached the person than CF (P<0.0080). In stimulus tests, foals were presented specific stimuli to which they had been tested as neonates. Two of eight CF were too unruly and dangerous to test. Of foals that could be tested, CF required significantly more time to hook-up a heart rate monitor (**P<0.0055). Split-plot analysis indicated that HF had lower heart rates to initial left-sided stimuli, presented first, than CF (*P<0.0421). In response to right-sided stimuli, heart rate scores of CF were not significantly different from HF (P<0.2259), suggesting reduced reactivity over time due to a learning effect. Behavioral responses to specific stimuli did not differ between CF and HF, suggesting that neonatal handling has a general rather than specific effect on subsequent behavior. Cortisol concentrations were measured before and after testing and the difference calculated. All foals had higher post-testing levels than pre-testing levels. There was a significant difference between HF and CF, indicating greater reactivity among the CF (*P<0.050). In general, the results indicated that foals handled as neonates were more tractable and less reactive. Specific neonatal handling tasks, such as sticking a finger up the foal's nose or patting the bottom of the foot, seemed to have no beneficial effect on related tasks such as passing a nasogastric tube or tapping with a farrier's hammer at 4 months of age. Mechanisms for the observed effect of neonatal handling require further investigation.
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