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Articles 271 - 300 of 407
Full-Text Articles in Comparative Psychology
Reflections On Animal Selves, Marc Bekoff, Paul W. Sherman
Reflections On Animal Selves, Marc Bekoff, Paul W. Sherman
Sentience Collection
Is self-cognizance a uniquely human attribute, or do other animals also have a sense of self? Although there is considerable interest in this question, answers remain elusive. Progress has been stymied by misunderstandings in terminology, a focus on a narrow range of species, and controversies over key concepts, experimental paradigms and interpretations of data. Here, we propose a new conceptual and terminological framework, emphasizing that degrees of self-cognizance differ among animals because of the cognitive demands that their species-specific social structures and life-history characteristics have placed upon them over evolutionary time. We suggest that the self-cognizance of an organism falls …
Environmental Enrichment And Prior Experience Of Live Prey Improve Foraging Behaviour In Hatchery-Reared Atlantic Salmon, C. Brown, T. Davidson, K. Laland
Environmental Enrichment And Prior Experience Of Live Prey Improve Foraging Behaviour In Hatchery-Reared Atlantic Salmon, C. Brown, T. Davidson, K. Laland
Aquaculture Collection
Atlantic salmon salmo salar L. parr were reared for 3 months under standard hatchery conditions or in a structurally enriched tank (containing plants, rocks and novel objects). Half of each of these fish had prior exposure to live prey in the form of live bloodworm while the other half were fed hatchery-pellets. After 12 days all fish were tested on a novel live prey item (brine shrimp). A significant interaction between the two factors (prior exposure to live prey and rearing condition) revealed that foraging performance was only enhanced in fish that had been reared in a complex environment and …
Novel Object Test: Examining Nociception And Fear In The Rainbow Trout, Lynne U. Sneddon, Victoria A. Braithwaite, Michael J. Gentle
Novel Object Test: Examining Nociception And Fear In The Rainbow Trout, Lynne U. Sneddon, Victoria A. Braithwaite, Michael J. Gentle
Veterinary Science and Medicine Collection
This study aimed to assess fear responses to a novel object while experiencing a noxious event to determine whether nociception or fear will dominate attention in a fish in novel object testing paradigm. This experimentally tractable animal model was used to investigate (1) the degree of neophobia to a novel object while experiencing noxious stimulation, (2) the response of the fish after removing the fear-causing event by using a familiar object, and (3) the effects of removing the nociceptive response by morphine administration and examining the response to a novel object. Control animals displayed a classic fear response to the …
Social Learning Of Prey Location In Hatchery-Reared Atlantic Salmon, C. Brown, A. Markula, K. Laland
Social Learning Of Prey Location In Hatchery-Reared Atlantic Salmon, C. Brown, A. Markula, K. Laland
Aquaculture Collection
Naïve, hatchery-reared Atlantic salmon Salmo salar parr were paired with demonstrators that had been pre-trained to accept live prey from the surface or from the benthos. After 6 days of observing demonstrators through a clear perspex partition the naïve fish’s benthic foraging skills were tested. The results revealed that hatchery-reared Atlantic salmon can be taught to target benthic prey items by observation alone and social learning protocols can be utilized to dramatically increase benthic foraging success. The results are discussed with reference to refining hatchery-rearing practices with a view to improving the post-release survival of hatchery fishes. The role of …
Habitat-Predator Association And Avoidance In Rainbowfish (Melanotaenia Spp.), Culum Brown
Habitat-Predator Association And Avoidance In Rainbowfish (Melanotaenia Spp.), Culum Brown
Sentience Collection
The ability to recall the location of a predator and later avoid it was tested in nine populations of rainbowfish (Melanotaenia spp.), representing three species from a variety of environments. Following the introduction of a model predator into a particular microhabitat, the model was removed, the arena rotated and the distribution of the fish recorded again. In this manner it could be determined what cues the fish relied on in order to recall the previous location of the predator model. Fish from all populations but one (Dirran Creek) were capable of avoiding the predator by remembering either the location and/or …
Considering Animals—Not “Higher” Primates, Marc Bekoff
Considering Animals—Not “Higher” Primates, Marc Bekoff
Sentience Collection
In this essay I argue that many nonhuman animal beings are conscious and have some sense of self. Rather than ask whether they are conscious, I adopt an evolutionary perspective and ask why consciousness and a sense of self evolved—what are they good for? Comparative studies of animal cognition, ethological investigations that explore what it is like to be a certain animal, are useful for answering this question. Charles Darwin argued that the differences in cognitive abilities and emotions among animals are differences in degree rather than differences in kind, and his view cautions against the unyielding claim that humans, …
A Simple Reason For A Big Difference: Wolves Do Not Look Back At Humans, But Dogs Do, Ádám Miklósi, Eniko Kubinyi, József Topál, Márta Gácsi, Zsófia Virányi, Vilmos Csányi
A Simple Reason For A Big Difference: Wolves Do Not Look Back At Humans, But Dogs Do, Ádám Miklósi, Eniko Kubinyi, József Topál, Márta Gácsi, Zsófia Virányi, Vilmos Csányi
Communication Skills Collection
The present investigations were undertaken to compare interspecific communicative abilities of dogs and wolves, which were socialized to humans at comparable levels. The first study demonstrated that socialized wolves were able to locate the place of hidden food indicated by the touching and, to some extent, pointing cues provided by the familiar human experimenter, but their performance remained inferior to that of dogs. In the second study, we have found that, after undergoing training to solve a simple manipulation task, dogs that are faced with an insoluble version of the same problem look/gaze at the human, while socialized wolves do …
The Bold And The Shy: Individual Differences In Rainbow Trout, L. U. Sneddon
The Bold And The Shy: Individual Differences In Rainbow Trout, L. U. Sneddon
Aquaculture Collection
Boldness and shyness were investigated as ‘personality’ traits in hatchery-reared rainbow trout Oncorhynchus mykiss. Bold fish spent more time in an open area and were more active than shy fish and these behaviours could be used as indicators of boldness and shyness. These differences were related to learning ability in a simple conditioning task. Bold fish learned the task more quickly than shy fish.
Play And The Evolution Of Fairness: A Game Theory Model, Lee Alan Dugatkin, Marc Bekoff
Play And The Evolution Of Fairness: A Game Theory Model, Lee Alan Dugatkin, Marc Bekoff
Ethology Collection
Bekoff [J. Consci. Stud. 8 (2001) 81] argued that mammalian social play is a useful behavioral phenotype on which to concentrate in order to learn more about the evolution of fairness. Here, we build a game theoretical model designed to formalize some of the ideas laid out by Bekoff, and to examine whether ‘fair’ strategies can in fact be evolutionarily stable. The models we present examine fairness at two different developmental stages during an individual’s ontogeny, and hence we create four strategies--fair at time 1/fair at time 2, not fair at time 1/not fair at time 2, fair at time …
Do Female Rainbowfish (Melanotaenia Spp.) Prefer To Shoal With Familiar Individuals Under Predation Pressure?, Culum Brown
Do Female Rainbowfish (Melanotaenia Spp.) Prefer To Shoal With Familiar Individuals Under Predation Pressure?, Culum Brown
Sentience Collection
Shoaling with familiar individuals may have many benefits including enhanced escape responses or increased foraging efficiency. This study describes the results of two complimentary experiments. The first utilised a simple binary choice experiment to determine if rainbowfish (Melanotaenia spp.) preferred to shoal with familiar individuals or with strangers. The second experiment used a “free range” situation where familiar and unfamiliar individuals were free to intermingle and were then exposed to a predator threat. Like many other small species of fish, rainbowfish were capable of identifying and distinguishing between individuals and choose to preferentially associate with familiar individuals as opposed to …
Social Learning Of A Novel Avoidance Task In The Guppy: Conformity And Social Release, Culum Brown, Kevin N. Laland
Social Learning Of A Novel Avoidance Task In The Guppy: Conformity And Social Release, Culum Brown, Kevin N. Laland
Sentience Collection
Studies of social learning suggest that many animals are disproportionately likely to adopt the behavior of the majority, and that this conformist transmission hinders the spread of novel behavioural variants. However, novel learned behaviour patterns regularly diffuse through animal populations. We propose a hypothesis, termed the ‘social release hypothesis’, that resolves these apparently conflicting findings by suggesting that animals are released from conforming to traditional behaviour in the absence of demonstrators. We investigated the role of pretrained, female demonstrator guppies, Poecilia reticulata, in influencing the escape response of untrained females to an artificial predator. Naïve ‘observer’ guppies were given the …
Vigilance And Predation Risk In Gunnison’S Prairie Dogs (Cynomys Gunnisoni), J. L. Verdolin, C. N. Slobodchikoff
Vigilance And Predation Risk In Gunnison’S Prairie Dogs (Cynomys Gunnisoni), J. L. Verdolin, C. N. Slobodchikoff
Sentience Collection
Group living in animals is believed to confer advantages related to a decrease in predation risk and an energetic trade-off between vigilance and foraging efficiency. Eight Gunnison’s prairie dog, Cynomys gunnisoni, colonies in Flagstaff, Arizona (elevation 2300 m), were studied from April to August 2000 to examine the adaptive significance of colonial living in the context of predation risk and antipredator behavioral strategies. Each colony was sampled once every 10 days for a period of 3 h. Upright and quadrepedal vigilance was recorded using scan samples. All predation events were recorded. Results suggest that vigilant behavior in Gunnison’s prairie dogs …
Physiology And Behavior Of Dogs During Air Transport, Renée Bergeron, Shannon L. Scott, Jean-Pierre Émond, Florent Mercier, Nigel J. Cook, Al L. Schaefer
Physiology And Behavior Of Dogs During Air Transport, Renée Bergeron, Shannon L. Scott, Jean-Pierre Émond, Florent Mercier, Nigel J. Cook, Al L. Schaefer
Stress Collection
Twenty-four beagles were used to measure physiological and behavioral reactions to air transport. Each of 3 groups of 4 sedated (with 0.5 mg/kg body weight of acepromazine maleate) and 4 non-sedated (control) dogs was flown on a separate flight between Montreal, Quebec, and Toronto, Ontario, after being transported by road from Quebec City to Montreal. Saliva and blood samples were taken before ground and air transport and after air transport. The heart rate was monitored during the whole experiment except during ground transport, and behavior was monitored by video during air transport. Sedation did not affect any of the variables …
Convergence Of Complex Cognitive Abilities In Cetaceans And Primates, Lori Marino
Convergence Of Complex Cognitive Abilities In Cetaceans And Primates, Lori Marino
Sentience Collection
What examples of convergence in higher-level complex cognitive characteristics exist in the animal kingdom? In this paper I will provide evidence that convergent intelligence has occurred in two distantly related mammalian taxa. One of these is the order Cetacea (dolphins, whales and porpoises) and the other is our own order Primates, and in particular the suborder anthropoid primates (monkeys, apes, and humans). Despite a deep evolutionary divergence, adaptation to physically dissimilar environments, and very different neuroanatomical organization, some primates and cetaceans show striking convergence in social behavior, artificial ‘language’ comprehension, and self-recognition ability. Taken together, these findings have important implications …
Cognitive And Communicative Abilities Of Grey Parrots, Irene M. Pepperberg
Cognitive And Communicative Abilities Of Grey Parrots, Irene M. Pepperberg
Sentience Collection
Grey parrots (Psittacus erithacus) solve various cognitive tasks and acquire and use English speech in ways that often resemble those of very young children. Given that the psittacine brain is organized very differently from that of mammals, these results have intriguing implications for the study and evolution of vocal learning, communication, and cognition.
Chimpanzees (Pan Troglodytes) Recognize Spatial And Object Correspondences Between A Scale Model And Its Referent, Valerie A. Kuhlmeier, Sarah T. Boysen
Chimpanzees (Pan Troglodytes) Recognize Spatial And Object Correspondences Between A Scale Model And Its Referent, Valerie A. Kuhlmeier, Sarah T. Boysen
Sentience Collection
In the present study, the contributions of spatial and object features to chimpanzees’ comprehension of scale models were examined. Seven chimpanzees that previously demonstrated the ability to use a scale model as an information source for the location of a hidden item were tested under conditions manipulating the feature correspondence and spatial-relational correspondence between objects in the model and an outdoor enclosure. In Experiment 1, subjects solved the task under two conditions in which one object cue (color or shape) was unavailable, but positional cues remained. Additionally, performance was above chance under a third condition in which both types of …
In Search Of King Solomon’S Ring: Cognitive And Communicative Studies Of Grey Parrots (Psittacus Erithacus), Irene M. Pepperberg
In Search Of King Solomon’S Ring: Cognitive And Communicative Studies Of Grey Parrots (Psittacus Erithacus), Irene M. Pepperberg
Sentience Collection
During the past 24 years, I have used a modeling technique (M/R procedure) to train Grey parrots to use an allospecific code (English speech) referentially; I then use the code to test their cognitive abilities. The oldest bird, Alex, labels more than 50 different objects, 7 colors, 5 shapes, quantities to 6, 3 categories (color, shape, material) and uses ‘no’, ‘come here’, wanna go X’ and ‘want Y’ (X and Y are appropriate location or item labels). He combines labels to identify, request, comment upon or refuse more than 100 items and to alter his environment. He processes queries to …
The Evolution Of Animal Play, Emotions, And Social Morality: On Science, Theology, Spirituality, Personhood, And Love, Marc Bekoff
The Evolution Of Animal Play, Emotions, And Social Morality: On Science, Theology, Spirituality, Personhood, And Love, Marc Bekoff
Attitudes Towards Animals Collection
My essay first takes me into the arena in which science, spirituality, and theology meet. I comment on the enterprise of science and how scientists could well benefit from reciprocal interactions with theologians and religious leaders. Next, I discuss the evolution of social morality and the ways in which various aspects of social play behavior relate to the notion of “behaving fairly.” The contributions of spiritual and religious perspectives are important in our coming to a fuller understanding of the evolution of morality. I go on to discuss animal emotions, the concept of personhood, and how our special relationships with …
Interactions Between Shoal Size And Conformity In Guppy Social Foraging, Rachel L. Day, Tom Macdonald, Culum Brown, Kevin N. Laland, Simon M. Reader
Interactions Between Shoal Size And Conformity In Guppy Social Foraging, Rachel L. Day, Tom Macdonald, Culum Brown, Kevin N. Laland, Simon M. Reader
Sentience Collection
Previous experimental studies have established that shoaling fish forage more effectively in large than small groups. We investigated how shoal size affects the foraging efficiency of laboratory populations of the guppy, Poecilia reticulata, exposed to different foraging tasks. Experiment 1 confirmed the prediction that in open water the first fish and focal fish of larger shoals locate food faster than in smaller shoals. However, a second experiment, in which shoals of fish were required to swim through a hole in an opaque partition to locate food, found the reverse pattern: smaller shoals learned to complete the task faster than large …
Familiarity With The Test Environment Improves Escape Responses In The Crimson Spotted Rainbowfish, Melanotaenia Duboulayi, Culum Brown
Sentience Collection
Animals that are familiar with their environment have been reported to have greater survivorship for a number of reasons related to their knowledge of the terrain, which they recall from memory. In an initial experiment rainbowfish significantly improved their escape response towards a novel trawl apparatus over a sequence of five runs. Escape latencies were still low during a subsequent exposure 11 months after the initial exposure. While part of the improvement in escape success was certainly due to learning associated with the location of the escape route, it is likely that this was aided by habituation to the tank …
Familiarity Facilitates Social Learning Of Foraging Behaviour In The Guppy, Will Swaney, Jeremy Kendal, Hannah Capon, Culum Brown, Kevin N. Laland
Familiarity Facilitates Social Learning Of Foraging Behaviour In The Guppy, Will Swaney, Jeremy Kendal, Hannah Capon, Culum Brown, Kevin N. Laland
Sentience Collection
Previous studies have shown that guppies, Poecilia reticulata, can learn the route to a food source by shoaling with knowledgeable conspecifics, and prefer to shoal with experienced foragers and familiar fish. We tested the hypothesis that guppies would learn more effectively from (1) familiar than unfamiliar demonstrators and (2) well-trained than poorly trained demonstrators. Demonstrator fish were given experience in swimming a route to a food source and then introduced into shoals of untrained observer guppies; the spread of this foraging skill was recorded over 15 trials. The demonstrators were either familiar or unfamiliar to the observers and either well …
The Effect Of Response Contingencies On Scale Model Task Performance By Chimpanzees (Pan Troglodytes), Valerie A. Kuhlmeier, Sarah T. Boysen
The Effect Of Response Contingencies On Scale Model Task Performance By Chimpanzees (Pan Troglodytes), Valerie A. Kuhlmeier, Sarah T. Boysen
Sentience Collection
The effects of modified procedures on chimpanzees' (Pan troglodytes) performance in a scale model comprehension task were examined. Seven chimpanzees that previously participated in a task in which they searched an enclosure for a hidden item after watching an experimenter hide a miniature item in the analogous location in a scale model were retested under procedures incorporating response costs. In Experiment 1, chimpanzees were trained under procedures that rewarded only item retrievals occurring on the 1st search attempt. During test trials, 6 chimpanzees performed above chance, including 4 that were previously unsuccessful under the original procedures (V. A. Kuhlmeier, S. …
Observations Of Scent-Marking And Discriminating Self From Others By A Domestic Dog (Canis Familiaris): Tales Of Displaced Yellow Snow, Marc Bekoff
Ethology Collection
Little is known about what stimuli trigger urinating or scent-marking in domestic dogs, Canis familiaris, or their wild relatives. While it is often suggested that the urine of other animals influences urinating and scent-marking patterns in canids, this has not been verified experimentally. To investigate the role of urine in eliciting urinating and marking, in this pilot study I moved urine-saturated snow (‘yellow snow’) from place-to-place during five winters to compare the responses of an adult male domestic dog, Jethro, to his own and others’ urine. Jethro spent less time sniffing his own urine than that of other males or …
Assessing The ‘Whole Animal’: A Free Choice Profiling Approach, Françoise Wemelsfelder, Tony E.A. Hunter, Michael T. Mendl, Alistair B. Lawrence
Assessing The ‘Whole Animal’: A Free Choice Profiling Approach, Françoise Wemelsfelder, Tony E.A. Hunter, Michael T. Mendl, Alistair B. Lawrence
Sentience Collection
The qualitative assessment of animal behaviour summarizes the different aspects of an animal’s dynamic style of interaction with the environment, using descriptors such as ‘confident’, ‘nervous’, ‘calm’ or ‘excitable’. Scientists frequently use such terms in studies of animal personality and temperament, but, wary of anthropomorphism, are reluctant to do so in studies of animal welfare. We hypothesize that qualitative behaviour assessment, in describing behaviour as an expressive process, may have a stronger observational foundation than is currently recognized, and may be of use as an integrative welfare assessment tool. To test this hypothesis, we investigated the inter- and intraobserver reliability …
Mammalian Play: Training For The Unexpected, Marek Špinka, Ruth C. Newberry, Marc Bekoff
Mammalian Play: Training For The Unexpected, Marek Špinka, Ruth C. Newberry, Marc Bekoff
Ethology Collection
In this review, we present a new conceptual framework for the study of play behavior, a hitherto puzzling array of seemingly purposeless and unrelated behavioral elements that are recognizable as play throughout the mammalian lineage. Our major new functional hypothesis is that play enables animals to develop flexible kinematic and emotional responses to unexpected events in which they experience a sudden loss of control. Specifically, we propose that play functions to increase the versatility of movements used to recover from sudden shock such as loss of balance and falling over, and to enhance the ability of animals to cope emotionally …
Mirror Self-Recognition In The Bottlenose Dolphin: A Case Of Cognitive Convergence, Diana Reiss, Lori Marino
Mirror Self-Recognition In The Bottlenose Dolphin: A Case Of Cognitive Convergence, Diana Reiss, Lori Marino
Sentience Collection
The ability to recognize oneself in a mirror is an exceedingly rare capacity in the animal kingdom. To date, only humans and great apes have shown convincing evidence of mirror self-recognition. Two dolphins were exposed to reflective surfaces, and both demonstrated responses consistent with the use of the mirror to investigate marked parts of the body. This ability to use a mirror to inspect parts of the body is a striking example of evolutionary convergence with great apes and humans.
Size Matters: Impact Of Item Size And Quantity On Array Choice By Chimpanzees (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson, Kimberly L. Mukobi
Size Matters: Impact Of Item Size And Quantity On Array Choice By Chimpanzees (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson, Kimberly L. Mukobi
Sentience Collection
The authors previously reported that chimpanzees (Pan troglodytes) showed a striking bias to select the larger of 2 candy arrays, despite a reversed reward contingency in which the animals received the smaller, nonselected array as a reward, except when Arabic numerals were used as stimuli. A perceptual or incentive-based interference occurred that was overcome by symbolic stimuli. The authors of the present study examined the impact of element size in choice arrays, using 1 to 5 large and small candies. Five test-sophisticated chimpanzees selected an array from the 2 presented during each trial. Their responses were not optimal, as animals …
Social Play Behaviour: Cooperation, Fairness, Trust, And The Evolution Of Morality, Marc Bekoff
Social Play Behaviour: Cooperation, Fairness, Trust, And The Evolution Of Morality, Marc Bekoff
Ethology Collection
No abstract provided.
Animal Suffering: An Invertebrate Perspective, Jennifer A. Mather
Animal Suffering: An Invertebrate Perspective, Jennifer A. Mather
Sentience Collection
Consideration of the welfare of other animals often is anthropocentric, focusing usually on mammals similar to humans. This article argues the necessity of evaluating the extension of such consideration more widely to invertebrates. Although unlike humans, some groups such as cephalopod molluscs probably have the potential for pain and suffering. In addition, a morality of care, rather than one of rights, and the damage humans do to themselves by cruel treatment of animals both argue for the extension of consideration to all animal species. This consideration predicts extension of basic care of cephalopods from simple housing and feeding into areas …
Modifying Water Nipples For Newborn Pigs, P. A. Phillips, D. Fraser
Modifying Water Nipples For Newborn Pigs, P. A. Phillips, D. Fraser
Learning Ability Collection
The use of bite nipples by piglets during the first six days after birth was monitored by time-lapse video recording. Simple bite nipples, mounted at a downward angle, were not discovered by most piglets within the six days, even after the nipple had been modified to drip water continuously. However, two modifications resulted in most piglets discovering the nipple within three days. These modifications were (1) mounting the nipple close to the floor with an upward angle and (2) adding a short length of chain to the valve lever