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Dugatkin, L. A. (1991). Dynamics of the TIT FOR TAT strategy during predator inspection in the guppy (Poecilia reticulata). Behav. Ecol. Sociobiol., 29(2), 127–132.
Abstract: One well-known solution to the iterated Prisoner's Dilemma is the TIT FOR TAT strategy. This strategy has three “characteristics” associated with it. TIT FOR TAT is nice (cooperates on the first move of a game), retaliatory (plays defect against an individual that defected on the prior move), and forgiving (cooperates with an individual which has defected in the past but cooperates in the present). Predator inspection behavior in guppies (Poecilia reticulata) was examined in order to determine whether guppies displayed these three characteristics. Results indicate that while it can be quite difficult to translate the abstract concepts of niceness, retaliation, and forgiveness into measurable behaviors, the data support the hypothesis that guppies display the three characteristics associated with the TIT FOR TAT strategy.
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Dugatkin, L. A., & Alfieri, M. (1991). Guppies and the TIT FOR TAT strategy: preference based on past interaction. Behav. Ecol. Sociobiol., 28(4), 243–246.
Abstract: The evolution of cooperation requires either (a) nonrandom interactions, such that cooperators preferentially interact with other cooperators, or (b) conditional behaviors, such that individuals act cooperatively primarily towards other cooperators. Although these conditions can be met without assuming sophisticated animal cognition, they are more likely to be met if animals can remember individuals with whom they have interacted, associate past interactions with these individuals, and base future behavior on this information. Here we show that guppies (Poecilia reticulata), in the context of predator inspection behavior, can identify and remember (for at least 4 h) the “more cooperative” among two conspecifics and subsequently choose to be near these individuals in future encounters.
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Dugatkin, L. A., & Earley, R. L. (2003). Group fusion: the impact of winner, loser, and bystander effects on hierarchy formation in large groups. Behav. Ecol., 14(3), 367–373.
Abstract: We present the results of a series of computer simulations that examined the impact of winner, loser, and bystander effects on hierarchy formation in fused groups. These effects and their implications for hierarchy structure and aggressive interactions were first examined in small four-member groups. Subsequent to this, the two small groups were fused into a single larger group. Further interactions took place in this fused group, generating a new hierarchy. Our models demonstrate clearly that winner, loser, and bystander effects strongly influence both the structure and types of interactions that emerge from the fusion of smaller groups. Four conditions produced results in which the same general patterns were uncovered in pre- and postfusion groups: (1) winner effects alone, (2) bystander loser effects alone, (3) winner and bystander winner effects operating simultaneously, and (4) all four effects in play simultaneously. Outside this parameter space, hierarchy structure and the nature of aggressive interactions differed in pre- and postfusion groups. When only loser effects were in play, one of the two clear alphas from the prefused groups dropped in rank in the eight-member fused group. When bystander winner effects were in play, it was difficult to rank any of the eight individuals in the fused group, and players interacted almost exclusively with those that were not in their original four-member group. When loser and bystander loser effects operated simultaneously, two top-ranking individuals emerged in the fused groups, but the relative rank of the other players was difficult to assign.
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Dugatkin, L. A., & Godin, J. - G. J. (1993). Female mate copying in the guppy (Poecilia reticulata): age-dependent effects. Behav. Ecol., 4(4), 289–292.
Abstract: Virtually all studies of mate choice to date have assumed that females choose mates independent of one another. Social cues, however, such as the mate choice of conspecifics, may also play an important role in such decisions. Previous work has shown that female guppies of similar age copy each other's choice of mates. Here we examine the effect of relative age on mate choice copying in the guppy, Poecilia reticulata, and examine whether younger individuals are more likely to copy the mate choice of older conspecifics than vice versa. Results indicate that younger females copy the mate choice of older females, but older individuals do not appear to be influenced by the mate choice of younger individuals.
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Dukas, R. (2004). Evolutionary Biology Of Animal Cognition. Annual Review of Ecology, Evolution, and Systematics, 35(1), 347–374.
Abstract: This review focuses on five key evolutionary issues pertaining to animal cognition, defined as the neuronal processes concerned with the acquisition, retention, and use of information. Whereas the use of information, or decision making, has been relatively well examined by students of behavior, evolutionary aspects of other cognitive traits that affect behavior, including perception, learning, memory, and attention, are less well understood. First, there is ample evidence for genetically based individual variation in cognitive traits, although much of the information for some traits comes from humans. Second, several studies documented positive association between cognitive abilities and performance measures linked to fitness. Third, information on the evolution of cognitive traits is available primarily for color vision and decision making. Fourth, much of the data on plasticity of cognitive traits appears to reflect nonadaptive phenotypic plasticity, perhaps because few evolutionary analyses of cognitive plasticity have been carried out. Nonetheless, several studies suggest that cognitive traits show adaptive plasticity, and at least one study documented genetically based individual variation in plasticity. Fifth, whereas assertions that cognition has played a central role in animal evolution are not supported by currently available data, theoretical considerations indicate that cognition may either increase or decrease the rate of evolutionary change.
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Eagle, N., & Pentland, A. (2009). Eigenbehaviors: identifying structure in routine. Behav. Ecol. Sociobiol., 63(7), 1057-1066.
Abstract: Longitudinal behavioral data generally contains a significant amount of structure. In this work, we identify the structure inherent in daily behavior with models that can accurately analyze, predict, and cluster multimodal data from individuals and communities within the social network of a population. We represent this behavioral structure by the principal components of the complete behavioral dataset, a set of characteristic vectors we have termed eigenbehaviors. In our model, an individual’s behavior over a specific day can be approximated by a weighted sum of his or her primary eigenbehaviors. When these weights are calculated halfway through a day, they can be used to predict the day’s remaining behaviors with 79% accuracy for our test subjects. Additionally, we demonstrate the potential for this dimensionality reduction technique to infer community affiliations within the subjects’ social network by clustering individuals into a behavior space spanned by a set of their aggregate eigenbehaviors. These behavior spaces make it possible to determine the behavioral similarity between both individuals and groups, enabling 96% classification accuracy of community affiliations within the population-level social network. Additionally, the distance between individuals in the behavior space can be used as an estimate for relational ties such as friendship, suggesting strong behavioral homophily amongst the subjects. This approach capitalizes on the large amount of rich data previously captured during the Reality Mining study from mobile phones continuously logging location, proximate phones, and communication of 100 subjects at MIT over the course of 9 months. As wearable sensors continue to generate these types of rich, longitudinal datasets, dimensionality reduction techniques such as eigenbehaviors will play an increasingly important role in behavioral research.
Keywords: Biomedical and Life Sciences
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Edwards, P. J., & Hollis, S. (1982). The Distribution of Excreta on New Forest Grassland Used by Cattle, Ponies and Deer. J Appl Ecol, 19(3), 953–964.
Abstract: (1) The distribution of excreta on areas of reseeded grassland in the New Forest used by free-ranging cattle, ponies and fallow deer was shown to be non-random. Distinct latrine areas were recognized where the faeces of all three herbivore species were concentrated, and where the majority of urinations occurred. The mosaic of latrine and non-latrine areas can be detected in aerial photographs in which non-latrine areas appear as light-grey patches set in a matrix of the dark grey latrine areas. During the 3 years of the study the position of the mosaic proved to be relatively stable. (2) The latrine areas were characterized by an uneven sward about 50 mm tall with abundant thistles (Cirsium spp.) and ragwort (Senecio jacobaea). Non-latrine areas had an even and very closely cropped sward between 10 and 20 mm tall. Soil chemical analysis of the two kinds of area revealed significantly higher levels of exchangeable potassium in latrine areas, and on one site significantly higher levels of magnesium and organic matter. No significant differences were detected in soil reaction, nor in phosphorus or calcium levels. (3) Observations of grazing animals revealed a tendency, at all times of year, for ponies to avoid grazing in latrine areas. In winter and spring this tendency was very slight, but from midsummer until late autumn a substantial majority of grazing ponies were to be found in non-latrine areas. In contrast, only 2% of the cattle observations made over a period of 20 months were of animals grazing in non-latrine areas. (4) The standing crop of dung and the rate of dung production on the two kinds of area were monitored for 12 months on one lawn. The amount of pony dung produced on non-latrine areas was only 16.5% of that in latrine areas, while for cattle the corresponding value was 28.7%. It is argued that the observed pattern has been created by selective grazing and eliminatory behaviour of the ponies, and that the excreta of cattle and deer are largely confined to pony latrine areas because these animals are unable to graze the very short herbage of non-latrine areas.
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Eisenberg, J. F., & Kleiman, D. G. (1972). Olfactory Communication in Mammals. Annu Rev Ecol Systemat, 3(1), 1–32.
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Ferrari, M. C. O., Capitania-Kwok, T., & Chivers, D. P. (2006). The role of learning in the acquisition of threat-sensitive responses to predator odours. Behav. Ecol. Sociobiol., 60(4), 522–527.
Abstract: The supposition that prey animals respond to a predator with an intensity that matches the risk posed by the predator is known as the threat-sensitive predator avoidance hypothesis. Many studies have provided support for this hypothesis; yet, few studies have attempted to determine how such abilities are acquired by prey species. In this study, we investigated whether fathead minnows (Pimephales promelas) could learn to recognize an unknown predator (northern pike, Esox lucius) in such a way that they could match the intensity of their antipredator response with the threat posed by the predator. We exposed pike-naive minnows to conspecific alarm cues paired with either a high or low concentration of pike odor. The following day, both groups were tested for a response to either high or low concentration of pike odor alone. We found that minnows conditioned with alarm cues paired with a given concentration of pike odor subsequently responded with a higher intensity to higher concentrations of pike odor, and with a lower intensity to lower concentrations of pike odor. These results demonstrate that during a single conditioning trial, minnows learn the identity of the predator in a threat-sensitive manner. Minnows use predator odor concentrations that they experience in subsequent interactions to adjust the intensity of their antipredator behavior. © Springer-Verlag 2006.
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Fischhoff, I., Dushoff, J., Sundaresan, S., Cordingley, J., & Rubenstein, D. (2009). Reproductive status influences group size and persistence of bonds in male plains zebra (Equus burchelli). Behav. Ecol. Sociobiol., 63(7), 1035-1043.
Abstract: Animal groups arise from individuals’ choices about the number, characteristics, and identity of associates. Individuals make these choices to gain benefits from their associations. As the needs of an individual change with its phenotype, so too we expect the nature of its associations to vary. In this paper, we investigate how the social priorities of male plains zebra (Equus burchelli) depend on reproductive state. An adult male is either a bachelor, and lacking mating access, or a stallion defending a harem. Multiple harems and bachelor males aggregate in larger herds. Herds frequently split and merge, affording males opportunities to change associates. Over a 4-year period, we sampled the herd associations in a population of 500–700 zebras. To isolate the effects of reproductive state on male social behavior, we account for potential confounding factors: changes in population size, grouping tendencies, and sampling intensity. We develop a generally applicable permutation procedure, which allows us to test the null hypothesis that social behavior is independent of male status. Averaging over all individuals in the population, we find that a typical bachelor is found in herds containing significantly more adults, bachelors, and stallions than the herds of a typical stallion. Further, bachelors’ bonds with each other are more persistent over time than those among stallions. These results suggest that bachelors form cohesive cliques, in which we may expect cooperative behaviors to develop. Stallion–stallion associations are more diffuse, and less conducive to long-term cooperation.
Keywords: Biomedical and Life Sciences
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