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Hogan, J. (2005). Causation: the study of behavioural mechanisms. Animal Biology (formerly Netherlands Journal of Zoology), 55(4), 323–341.
Abstract: This paper describes current work on the causal analysis of behaviour systems. It is noted that while causal work investigating the neural, hormonal, and genetic bases of behaviour is flourishing, work being conducted at a strictly behavioural level of analysis has declined greatly over the past 40 years. Nonetheless, most recent research on animal cognition and applied ethology is still being carried out at a behavioural level of analysis and examples of both types of research are presented: memory mechanisms of food-storing birds and decisions of spider-eating jumping spiders, as well as feather pecking in fowl and animal welfare issues, are all briefly discussed. Finally, I discuss the similarities between neural network modelling and early ethological models of motivation, and then show how a modern version of Lorenz's model of motivation can account for current research findings on dustbathing in chickens and sleep in humans. I conclude that valuable information can still be obtained by research at a behavioural level of analysis.
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Reader, S. M. (2003). Innovation and social learning: individual variation and brain evolution. Anim. Biol. Leiden., 53(2), 147–158.
Abstract: This paper reviews behavioural, neurological and cognitive correlates of innovation at the individual, population and species level, focusing on birds and primates. Innovation, new or modified learned behaviour not previously found in the population, is the first stage in many instances of cultural transmission and may play an important role in the lives of animals with generalist or opportunistic lifestyles. Within-species, innovation is associated with low neophobia, high neophilia, and with high social learning propensities. Indices of innovatory propensities can be calculated for taxonomic groups by counting the frequency of reports of innovation in published literature. These innovation rate data provide a useful comparative measure for studies of behavioural flexibility and cognition. Innovation rate is positively correlated with the relative size of association areas in the brain, namely the hyperstriatum ventrale and neostriatum in birds, and the neocortex and striatum in primates. Innovation rate is also positively correlated with the reported variety of tool use, as well as interspecific differences in learning. Current evidence thus suggests similar patterns of cognitive evolution in primates and birds.
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Bolhuis, J. (2005). Function and mechanism in neuroecology: looking for clues. Animal Biology (formerly Netherlands Journal of Zoology), 55(4), 457–490.
Abstract: The four questions that Niko Tinbergen identified for behavioural biology ? evolution, function, development and causation ? are all important and should be studied in their own right. Recently, there has been a debate as to whether these four questions should be investigated separately or whether they should be integrated. Integration of the four questions has been attempted in novel research disciplines such as cognitive ecology, evolutionary psychology and neuroecology. Euan Macphail and I have criticised these integrative approaches, suggesting that they are fundamentally flawed as they confound function and mechanism. Investigating the function or evolutionary history of a behaviour or cognitive system is important and entirely legitimate. However, such investigations cannot provide us with answers to questions about the mechanisms underlying behaviour or cognition. At most, functional or evolutionary considerations can provide clues that may be useful for a causal analysis of the underlying mechanisms. However, these clues can be misleading and are often wrong, as is illustrated with examples from song learning and food storing in birds. After summarising the main issues in the neuroecology debate, I discuss some misunderstandings that were apparent in the responses to our critique, as well as some recent relevant data. Recent results do not support the neuroecological approach. Finally, I suggest that the way forward is a cautious and critical use of functional and evolutionary clues in the study of the mechanisms of behaviour.
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Geisbauer, G., Griebel, U., Schmid, A., & Timney, B. (2004). Brightness discrimination and neutral point. Can. J. Zool, 82(4), 660–670.
Abstract: Abstract: Equine brightness discrimination ability and color discrimination were measured using a two-choice discrimination
task. Two Haflinger horses (Equus caballus L., 1758) were trained to discriminate 30 different shades of grey varying from low to high relative brightness. Their ability to distinguish shades of grey was poor, with calculated Weber fractions of 0.42 and 0.45. In addition, a “neutral point” test to determine the dimensionality of color vision was carried out. Three hues of blue-green were tested versus a range of grey targets with brightnesses similar to those of the blue-green targets. A neutral point was found at about 480 nm. Thus, we can conclude that horses possess dichromatic color vision. |
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Weckerly, F. W. (1999). Social bonding and aggression in female Roosevelt elk. Can J Zool, 77(9), 1379–1384.
Abstract: Abstract: The relationship between degree of social bonding (extent of association among individuals) and level of aggression in ruminants is unclear. I examined social bonding and aggression in three groups of female Roosevelt elk (Cervus elaphus roosevelti) over 2 years. I hypothesized that when animals are socially bonded, bouts of aggression will be won by the individual initiating the aggression, occur quickly, and involve little physical contact, and the level of aggression does not correlate with group size. The degree of social bonding was high among individuals in all groups. Dyads of known individuals were together >80% of the time. A permutation analysis indicated that groups with the observed sizes had <0.001 chance of random association, except on one occasion when the probability was 0.72 for one group. Using focal-animal sampling, aggressive interactions were won 72% of the time by the initiator, occurred quickly (<5 s), and involved little physical contact, and the level of aggression was not correlated with group size. The level of aggression was, however, significantly lower in one of the groups. This group may have had access to more abundant food resources than the other groups. Socially bonded elk conducted aggressive interactions in a fashion that did not disrupt social stability. Résumé : La relation entre le degré de liaison sociale (importance des associations entre individus) et l`agressivité n`est pas claire chez les ruminants. J`ai étudié les liaisons sociales et l`agressivité chez trois groupes de femelles du Cerf de Roosevelt (Cervus elaphus roosevelti) pendant 2 ans. J`ai posé en hypothèse que, chez les animaux liés socialement, la victoire devrait être emportée par l`individu qui entreprend l`agression, l`agression devrait être de courte durée, se faire avec peu de contacts physiques et la fréquence des agressions ne devrait pas être liée à la taille du groupe. Des paires d`individus passaient plus de 80% de leur temps ensemble. Une analyse des permutations a démontré que, chez les groupes des tailles observées, la probabilité d`une association aléatoire était de moins de 0,001, sauf en un cas où cette probabilité a été évaluée à 0,72 chez un groupe. Par échantillonnage directionnel, j`ai observé que les interactions agressives étaient gagnées par l`individu attaquant 72% du temps, étaient de courte durée (<5 s), se faisaient avec peu de contacts physiques et leur fréquence n`était pas reliée à la taille du groupe. Il y avait cependant moins d`agressivité chez l`un des groupes. Il se peut que ce groupe ait eu accès à plus de ressources alimentaires que les autres. Chez les cerfs liés par des liens sociaux, l`agressivité ne se manifeste pas de façon à déséquilibrer la stabilité sociale.
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Peterson R.O., Jacobs A.K., Drummer T.D., Mech L.D., & Smith D.W. (2002). Leadership behavior in relation to dominance and reproductive status in gray wolves, Canis lupus. Canadian Journal of Zoology, 80, 1405–1412.
Abstract: We analyzed the leadership behavior of breeding and nonbreeding gray wolves (Canis lupus) in three packs during winter in 1997-1999. Scent-marking, frontal leadership (time and frequency in the lead while traveling), initiation of activity, and nonfrontal leadership were recorded during 499 h of ground-based observations in Yellowstone National Park. All observed scent-marking (N = 158) was done by breeding wolves, primarily dominant individuals. Dominant breeding pairs provided most leadership, consistent with a trend in social mammals for leadership to correlate with dominance. Dominant breeding wolves led traveling packs during 64% of recorded behavior bouts (N = 591) and 71% of observed travel time (N = 64 h). During travel, breeding males and females led packs approximately equally, which probably reflects high parental investment by both breeding male and female wolves. Newly initiated behaviors (N = 104) were prompted almost 3 times more often by dominant breeders (70%) than by nonbreeders (25%). Dominant breeding females initiated pack activities almost 4 times more often than subordinate breeding females (30 vs. 8 times). Although one subordinate breeding female led more often than individual nonbreeders in one pack in one season, more commonly this was not the case. In 12 cases breeding wolves exhibited nonfrontal leadership. Among subordinate wolves, leadership behavior was observed in subordinate breeding females and other individuals just prior to their dispersal from natal packs. Subordinate wolves were more often found leading packs that were large and contained many subordinate adults.
Nous avons analysé le comportement de commandement chez des loups gris (Canis lupus) reproducteurs et non reproducteurs appartenant à trois meutes durant les hivers de 1997-1999. Le marquage d'odeurs, la position en tête de meute (la durée et la fréquence au cours des déplacements), l'initiation des activités et la prise de décisions ailleurs qu'en tête du groupe ont été notés pendant 499 h d'observations au sol dans le Parc national de Yellowstone. Tous les marquages (N = 158) ont été faits par des loups reproducteurs, surtout des individus dominants. Ce sont surtout les couples dominants qui assurent le commandement, en accord avec une tendance chez les mammifères sociaux chez lesquels la fonction de chef est en corrélation avec la dominance. Les loups reproducteurs dominants ont conduit les meutes en déplacement pendant 64 % (N = 591) des épisodes de comportement et pendant 71 % des épisodes de déplacement (N = 64 h). Les mâles et les femelles reproducteurs ont dirigé les meutes en déplacement à peu près également, ce qui reflète probablement l'investissement parental important aussi bien de la part des reproducteurs mâles que des femelles. Les comportements nouveaux (N = 104) ont été adoptés presque trois fois plus souvent par des reproducteurs dominants (70 %) que par des individus non reproducteurs (25 %). Des femelles reproductrices dominantes ont été instigatrices des activités de leur meute environ quatre fois plus souvent que les femelles reproductrices subordonnées (30 vs. 8 fois). Bien qu'une femelle reproductrice subordonnée ait pris la direction de sa meute plus souvent que les individus non reproducteurs au cours d'une saison, cela n'est pas habituel. Dans 12 cas, des loups reproducteurs ont pris la direction de leur meute sans être en tête. Chez les individus subordonnés, le comportement de commandement a été observé chez des femelles reproductrices et chez d'autres individus juste avant qu'ils ne quittent leur meute d'origine au moment de la dispersion. Les loups subordonnés mènent surtout de grands troupeaux qui comptent beaucoup d'individus subordonnés.[Traduit par la Rédaction] |
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Chase, I. D. (2006). Music notation: a new method for visualizing social interaction in animals and humans. Front Zool, 3, 18.
Abstract: ABSTRACT: BACKGROUND: Researchers have developed a variety of techniques for the visual presentation of quantitative data. These techniques can help to reveal trends and regularities that would be difficult to see if the data were left in raw form. Such techniques can be of great help in exploratory data analysis, making apparent the organization of data sets, developing new hypotheses, and in selecting effects to be tested by statistical analysis. Researchers studying social interaction in groups of animals and humans, however, have few tools to present their raw data visually, and it can be especially difficult to perceive patterns in these data. In this paper I introduce a new graphical method for the visual display of interaction records in human and animal groups, and I illustrate this method using data taken on chickens forming dominance hierarchies. RESULTS: This new method presents data in a way that can help researchers immediately to see patterns and connections in long, detailed records of interaction. I show a variety of ways in which this new technique can be used: (1) to explore trends in the formation of both group social structures and individual relationships; (2) to compare interaction records across groups of real animals and between real animals and computer-simulated animal interactions; (3) to search for and discover new types of small-scale interaction sequences; and (4) to examine how interaction patterns in larger groups might emerge from those in component subgroups. In addition, I discuss how this method can be modified and extended for visualizing a variety of different kinds of social interaction in both humans and animals. CONCLUSION: This method can help researchers develop new insights into the structure and organization of social interaction. Such insights can make it easier for researchers to explain behavioural processes, to select aspects of data for statistical analysis, to design further studies, and to formulate appropriate mathematical models and computer simulations.
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Larsson, M. (2013). The optic chiasm: a turning point in the evolution of eye/hand coordination. Front. Zool., 10(1), 41.
Abstract: The primate visual system has a uniquely high proportion of ipsilateral retinal projections, retinal ganglial cells that do not cross the midline in the optic chiasm. The general assumption is that this developed due to the selective advantage of accurate depth perception through stereopsis. Here, the hypothesis that the need for accurate eye-forelimb coordination substantially influenced the evolution of the primate visual system is presented. Evolutionary processes may change the direction of retinal ganglial cells. Crossing, or non-crossing, in the optic chiasm determines which hemisphere receives visual feedback in reaching tasks. Each hemisphere receives little tactile and proprioceptive information about the ipsilateral hand. The eye-forelimb hypothesis proposes that abundant ipsilateral retinal projections developed in the primate brain to synthesize, in a single hemisphere, visual, tactile, proprioceptive, and motor information about a given hand, and that this improved eye-hand coordination and optimized the size of the brain. If accurate eye-hand coordination was a major factor in the evolution of stereopsis, stereopsis is likely to be highly developed for activity in the area where the hands most often operate.The primate visual system is ideally suited for tasks within arm's length and in the inferior visual field, where most manual activity takes place. Altering of ocular dominance in reaching tasks, reduced cross-modal cuing effects when arms are crossed, response of neurons in the primary motor cortex to viewed actions of a hand, multimodal neuron response to tactile as well as visual events, and extensive use of multimodal sensory information in reaching maneuvers support the premise that benefits of accurate limb control influenced the evolution of the primate visual system. The eye-forelimb hypothesis implies that evolutionary change toward hemidecussation in the optic chiasm provided parsimonious neural pathways in animals developing frontal vision and visually guided forelimbs, and also suggests a new perspective on vision convergence in prey and predatory animals.
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Kaiser, S., Hennessy, M. B., & Sachser, N. (2015). Domestication affects the structure, development and stability of biobehavioural profiles. Frontiers in Zoology, 12(1), 1–11.
Abstract: Domestication is an evolutionary process during which the biobehavioural profile (comprising e.g. social and emotional behaviour, cognitive abilities, as well as hormonal stress responses) is substantially reshaped. Using a comparative approach, and focusing mainly on the domestic and wild guinea pig, an established model system for the study of domestication, we review (a) how wild and domestic animals of the same species differ in behaviour, emotion, cognition, and hormonal stress responses, (b) during which phases of life differences in biobehavioural profiles emerge and (c) whether or not animal personalities exist in both the wild and domestic form. Concerning (a), typical changes with domestication include increased courtship, sociopositive and maternal behaviours as well as decreased aggression and attentive behaviour. In addition, domestic animals display more anxiety-like and less risk-taking and exploratory behaviour than the wild form and they show distinctly lower endocrine stress responsiveness. There are no indications, however, that domestic animals have diminished cognitive abilities relative to the wild form. The different biobehavioural profiles of the wild and domestic animals can be regarded as adaptations to the different environmental conditions under which they live, i.e., the natural habitat and artificial man-made housing conditions, respectively. Concerning (b), the comparison of infantile, adolescent and adult wild and domestic guinea pigs shows that the typical biobehavioural profile of the domestic form is already present during early phases of life, that is, during early adolescence and weaning. Thus, differences between the domestic and the wild form can be attributed to genetic alterations resulting from artificial selection, and likely to environmental influences during the pre- and perinatal phase. Interestingly, the frequency of play behaviour does not differ between the domestic and wild form early in life, but is significantly higher in domesticated guinea pigs at later ages. Concerning (c), there is some evidence that personalities occur in both wild and domestic animals. However, there may be differences in which behavioural domains – social and sexual behaviour, emotionality, stress-responsiveness – are consistent over time. These differences are probably due to changing selection pressures during domestication.
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Briefer, E. F., Mandel, R., Maigrot, A. - L., Briefer Freymond, S., Bachmann, I., & Hillmann, E. (2017). Perception of emotional valence in horse whinnies. Frontiers in Zoology, 14(1), 8.
Abstract: Non-human animals often produce different types of vocalisations in negative and positive contexts (i.e. different valence), similar to humans, in which crying is associated with negative emotions and laughter is associated with positive ones. However, some types of vocalisations (e.g. contact calls, human speech) can be produced in both negative and positive contexts, and changes in valence are only accompanied by slight structural differences. Although such acoustically graded signals associated with opposite valence have been highlighted in some species, it is not known if conspecifics discriminate them, and if contagion of emotional valence occurs as a result. We tested whether domestic horses perceive, and are affected by, the emotional valence of whinnies produced by both familiar and unfamiliar conspecifics. We measured physiological and behavioural reactions to whinnies recorded during emotionally negative (social separation) and positive (social reunion) situations.
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