Comparative Psychology Commons^™

Possible Levels Of Animal Consciousness With Reference To Grey Parrots (Psittacus Erithacus), Irene M. Pepperberg, Spencer K. Lynn

Sentience Collection

Researchers often study nonhuman abilities by assuming their subjects form representations about perceived stimuli and then process such information; why then would consciousness be required, and, if required, at what level? Arguments about nonhuman consciousness range from claims of levels comparable to humans to refutation of any need to study such phenomena. We suggest that (a) species exhibit different levels attuned to their ecological niches, and (b) animals, within their maximum possible level, exhibit different extents of awareness appropriate to particular situations, much like humans (presumably conscious) who often act without conscious awareness of factors controlling their behavior. We propose …

Spontaneous Discrimination Of Natural Stimuli By Chimpanzees (Pan Troglodytes), David A. Brown, Sarah T. Boysen

Sentience Collection

Six chimpanzees (Pan troglodytes) were presented with pairs of color photographic images of 5 different categories of animals (cat, chimp, gorilla, tiger, fish). The subjects responded to each pair using symbols for "same" and "different." Both within- and between-category discriminations were tested, and all chimpanzees classified the image pairs in accordance with the 5 experimenter-defined categories under conditions of nondifferential reinforcement. Although previous studies have demonstrated identification or discrimination of natural categories by nonhuman animals, subjects were typically differentially reinforced for their responses. The present findings demonstrate that chimpanzees can classify natural objects spontaneously and that such classifications may be …

Animal Minds And Animal Emotions, Marian Stamp Dawkins

Emotion Collection

The possibility of conscious experiences of emotions in non-human animals has been much less explored than that of conscious experiences associated with carrying out complex cognitive tasks. However, no great cognitive powers are needed to feel hunger or pain and it may be that the capacity to feel emotions is widespread in the animal kingdom. Since plants can show surprisingly sophisticated ‘‘choice’’ and ‘‘decision-making’’ mechanisms and yet we would not wish to imply that they are conscious, attribution of emotions to animals has to be done with care. Whether or not an animal possesses anticipatory mechanisms associated with positive and …

Animal Emotions: Exploring Passionate Natures, Marc Bekoff

Sentience Collection

No abstract provided.

Primate Numerical Competence: Contributions Toward Understanding Nonhuman Cognition, Sarah T. Boysen, Karen I. Hallberg

Sentience Collection

Nonhuman primates represent the most significant extant species for comparative studies of cognition, including such complex phenomena as numerical competence, among others. Studies of numerical skills in monkeys and apes have a long, though somewhat sparse history, although questions for current empirical studies remain of great interest to several fields, including comparative, developmental, and cognitive psychology; anthropology; ethology; and philosophy, to name a few. In addition to demonstrated similarities in complex information processing, empirical studies of a variety of potential cognitive limitations or constraints have provided insights into similarities and differences across the primate order, and continue to offer theoretical …

Mixing At Young Ages Reduces Fighting In Unacquainted Domestic Pigs, Anton D. Pitts, Daniel M. Weary, Edmond A. Pajor, David Fraser

Agonistic Behavior Collection

Under normal farming practices, piglets from different litters are often mixed around the time of weaning, and a high incidence of fighting and minor injuries often occur. The aim of this experiment was to determine the effect of age on the incidence of fighting in piglets mixed before weaning, at different ages between 5 and 26 days. We found no significant relationship between age and the likelihood that a pair of piglets would fight during the first 75 min after mixing. However, the duration of the first fight observed increased from 101±38 s at 5 days to 621±278 s at …

Bubble Ring Play Of Bottlenose Dolphins (Tursiops Truncatus): Implications For Cognition, Brenda Mccowan, Lori Marino, Erik Vance, Leah Walke, Diana Reiss

Sentience Collection

Research on the cognitive capacities of dolphins and other cetaceans (whales and porpoises) has importance for the study of comparative cognition, particularly with other large-brained social mammals, such as primates. One of the areas in which cetaceans can be compared with primates is that of object manipulation and physical causality, for which there is an abundant body of literature in primates. The authors supplemented qualitative observations with statistical methods to examine playful bouts of underwater bubble ring production and manipulation in 4 juvenile male captive bottlenose dolphins (Tursiops truncatus). The results are consistent with the hypothesis that dolphins monitor the …

Regulation Of Contact With Offspring By Domestic Sows: Temporal Patterns And Individual Variation, E. A. Pajor, D. L. Kramer, D. Fraser

Rearing Behavior Collection

We used a sow-controlled housing system to examine temporal and individual variation in the tendency of sows to associate with young. During a 5-week lactation, 22 sows and litters were housed in a pen where the sow could freely leave and re-enter the piglets' area by stepping over a barrier that the piglets could not cross. Despite this option, the sows remained with the piglets almost constantly during the 1st day after birth. Nineteen sows ('leavers') changed to spending most of their time away from the litter at some point in the lactation. The change was rapid, often within a …

A Preliminary Investigation Of The Construct Of Psychopathic Personality (Psychopathy) In Chimpanzees (Pan Troglodytes), Scott O. Lilienfeld, Jonathan Gershon, Marshall Duke, Lori Marino, Frans B. M. De Waal

Sentience Collection

Although the construct of psychopathy has received considerable attention in humans, its relevance to other animals is largely unknown. We developed a measure of psychopathy for use in chimpanzees (Pan troglodytes), the Chimpanzee Psychopathy Measure (CPM), and asked 6 raters to complete this index on 34 chimpanzees. The CPM (a) demonstrated satisfactory interrater reliability and internal consistency; (b) exhibited marginally significant sex differences (males > females); (c) correlated positively with measures of extraversion, agreeableness, and observational ratings of agonism, sexual activity, daring behaviors, teasing, silent bluff displays, and temper tantrums, and negatively with observational ratings of generosity; and (d) demonstrated incremental …

Social Mechanisms Enhance Escape Responses In Shoals Of Rainbowfish, Melanotaenia Duboulayi, Culum Brown, Kevin Warburton

Aquaculture Collection

Shoaling behaviour has been shown to provide many benefits to group members. In this study we examined the ability of fish shoals to escape from a novel trawl apparatus. Fish in shoals of 5 found, and escaped through, a hole in the oncoming trawl more quickly than fish in pairs. Fish in the larger shoals displayed a significant decrease in escape latencies over a series of five trawls, providing clear evidence of net avoidance learning, whereas fish in pairs showed no evidence of learning over successive runs. Observations suggested that more information on the location of the escape route was …

Scale-Model Comprehension By Chimpanzees (Pan Troglodytes), Valerie A. Kuhlmeier, Sarah T. Boysen, Kimberly L. Mukobi

Sentience Collection

The ability of chimpanzees (Pan troglodytes) to recognize the correspondence between a scale model and its real-world referent was examined. In Experiments 1 and 2, an adult female and a young adult male watched as an experimenter hid a miniature model food in 1 of 4 sites in a scale model. Then, the chimpanzees were given the opportunity to find the real food item that had been hidden in the analogous location in the real room. The female performed significantly above chance, whereas the male performed at chance level. Experiments 3 and 4 tested 5 adult and 2 adolescent chimpanzees …

Predicting Flock Vigilance From Simple Passerine Interactions: Modelling With Cellular Automata, David B. Bahr, Marc Bekoff

Ethology Collection

Vigilance in flocks can be described and modelled as a plausible set of local interactions between neighbouring birds. Each bird in the modelled flock chooses to feed or to scan based solely on whether or not its neighbours are feeding or scanning. This simple model has the ability both to reproduce observations that have not been previously explained and to predict flock behaviours that might be confirmed with future field studies. Examples include simulations showing decreased vigilance with increased flock size (as observed in the field), greater time spent scanning when obstacles such as trees are present (as observed) and …

Asymmetry And Fighting Performance In The Shore Crab Carcinus Maenas, Lynne U. Sneddon, John P. Swaddle

Veterinary Science and Medicine Collection

Fluctuating asymmetries (left–right differences in symmetric traits) can be negatively related to fitness parameters in a number of biological systems. Hence, it has been suggested that symmetric individuals should outcompete asymmetric individuals during intraspecific agonistic encounters. However, there is a lack of experimental evidence for such a relationship. We investigated the relationship between trait asymmetry (both directional and fluctuating asymmetry) and the outcome of agonistic encounters among size-matched male shore crabs. Our findings indicate that cheliped (‘weapon claw’) directional asymmetry is not related to the outcome of fights, whereas fluctuating asymmetry in the fifth pereiopod, but not the second pereiopod, …

Overcoming Response Bias Using Symbolic Representations Of Number By Chimpanzees (Pan Troglodytes), Sarah T. Boysen, Kimberly L. Mukobi, Gary G. Berntson

Sentience Collection

We previously reported that chimpanzees were unable to optimally select the smaller of two candy arrays in order to receive a larger reward. When Arabic numerals were substituted for the candy arrays, animals who had had prior training with numerical symbols showed an immediate and significant improvement in performance and were able to select reliably the smaller numeric representation in order to obtain a larger reward. Poor performance with candy arrays was interpreted as reflecting a response bias toward the intrinsic incentive and/or perceptual features of the larger array. In contrast, the Arabic numerals represent numerosity symbolically and appear to …

Behavioral Interactions And Conflict Among Domestic Dogs, Black-Tailed Prairie Dogs, And People In Boulder, Colorado, Marc Bekoff, Robert W. Ickes

Ethology Collection

Interactions among domestic dogs (Canis familiaris), black-tailed prairie dogs (Cynomys ludovicianus), and people were studied at Dry Creek, Boulder, Colorado. Our objective was to develop a basic understanding of the nature of dog–prairie dog interactions in this recreational area, because this is an issue that has high visibility and over which there is conflict in Boulder: There are those who want dogs to run free regardless of their impact on the behavior and lives of prairie dogs and those who want to protect prairie dogs and have dogs restrained or go elsewhere. We found that dogs clearly influenced the behavior …

Geographic Variation In Alarm Calls Of Gunnison's Prairie Dogs, C. N. Slobodchikoff, S. H. Ackers, M. Van Ert

Communication Skills Collection

Geographic variation in alarm calls of Gunnison's prairie dogs (Cynomys gunnisoni) was analyzed at regional and local scales. Alarm calls in response to a common stimulus (the same human) were recorded at four colonies near Flagstaff, Arizona, and at six sites throughout the southwestern United States. The acoustic structure of calls was analyzed for seven call variables. Regional differences fit the prediction of greater differences with increased geographical separation. Differences between colonies at a local scale were not related to geographical distance, suggesting that local dialects exist within a region. Differences in the level of predation by humans …

Impact Of An Ecological Factor On The Costs Of Resource Acquisition: Fighting And Metabolic Physiology Of Crabs, L. U. Sneddon, F. A. Huntingford, A. C. Taylor

Ethology Collection

1. Current game theory models and recent experimental evidence suggests that the strategy an animal adopts in agonistic encounters is determined by individual state. Therefore manipulation of an individual’s state should elicit different behavioural responses. In this paper, mechanisms are examined that underlie state-dependent strategies using Shore Crabs, Carcinus maenas, and how, by altering the environment, behaviour and physiology are affected.
2. Fights were staged between pairs of male crabs under normoxic and severely hypoxic (< 15 torr) conditions to determine if the metabolic costs of fighting and resource acquisition are affected by water P_O2. After fighting, blood and tissue samples from each crab were taken and analysed for metabolites associated with anaerobiosis (L-lactate, glucose and glycogen).
3. The spectrum …

‘Pleasures’, ‘Pains’ And Animal Welfare: Toward A Natural History Of Affect, D. Fraser, I. J.H. Duncan

Animal Welfare Collection

In hedonic theories of motivation, 'motivational affective states' (MASs) are typically seen as adaptations which motivate certain types of behaviour, especially in situations where a flexible or learned response is more adaptive than a rigid or reflexive one. MASs can be negative (eg unpleasant feelings of hunger or pain) or positive (eg pleasant feelings associated with eating and playing). Hedonic theories often portray negative and positive MASs as opposite ends of a one-dimensional scale.

We suggest that natural selection has favoured negative and positive affect as separate processes to solve two different types of motivational problems. We propose that negative …

Translocation Effects On The Behavior Of Black-Tailed Prairie Dogs (Cynomys Ludovicianus), John P. Farrar, Karin L. Coleman, Marc Bekoff, Eric Stone

Ethology Collection

We examined the effects of translocation on Black-tailed prairie dog (Cynomys ludovicianus) anti-predator behavior by recording response distances and response times to a human intruder in three colonies containing native, translocated, and combined native and translocated prairie dogs. The translocated prairie dogs barked alarms and concealed themselves at significantly greater intruder distances than mixed or native colonies. However, individuals in different colonies did not differ in the time taken to return to a burrow, to conceal themselves after a human approached the colony, or in the time elapsed after concealment until an animal reappeared. Translocated prairie dogs exhibited nearly twice …

Farrowing Behaviour And Stillbirth In Two Environments: An Evaluation Of The Restraint-Stillbirth Hypothesis, D. Fraser, P. A. Phillips, B. K. Thompson

Reproductive Behavior Collection

A total of 59 farrowings were studied in either a conventional, narrow farrowing crate (0.43 m wide) or a much wider alternative design with sides spaced 1.2 m apart at the sow’s standing height but narrowing near the floor to limit the sow’s lying area. Using video recording, we monitored each “birth interval” (i.e. the period between two successive births) and noted the interval’s length, the sow’s posture and postural changes during the interval, and whether the interval ended with a live-born or stillborn piglet. The wide and conventional crates did not differ significantly in median interval between piglets (15.9 …

Weapon Size Versus Body Size As A Predictor Of Winning In Fights Between Shore Crabs, Carcinus Maenas (L.), Lynne U. Sneddon, Felicity A. Huntingford, Alan C. Taylor

Veterinary Science and Medicine Collection

Relative body size (carapace width) and weapon size (chela length) were used as indicators of resource holding potential (RHP) in the agonistic behaviour of male shore crabs, Carcinus maenas (L.). Weapon size was found to be a more reliable predictor of the outcome of pairwise fights than body size. Crabs with longer chelae than their opponents were more likely to win fights than crabs with relatively larger bodies. Body size had less influence on the outcome of fights. Relative body and weapon size did not influence initiation of contests but did affect the likelihood of winning; however, this was significant …

Life In Captivity: Its Lack Of Opportunities For Variable Behaviour, Françoise Wemelsfelder

Zoos and Aquariums Collection

No abstract provided.

Vocalizations By Isolated Piglets: A Reliable Indicator Of Piglet Need Directed Towards The Sow, Daniel M. Weary, Stephen Ross, David Fraser

Communication Skills Collection

When suckling piglets are isolated from the sow and litter-mates they vocalize a great deal. Sows also call when isolated from their piglets. In one experiment, we found that isolated piglets doubled their call rate in response to playback of sow calls, indicating that piglets are directing calls towards the sow. In a second experiment, we found that variation in the piglet isolation calls related to aspects of the piglet's condition: piglets isolated for 13 min in an enclosure kept at approximately 14°C called more, used higher frequency calls and longer calls, than litter-mates isolated in an enclosure kept at …

The Scientific Validity Of Subjective Concepts In Models Of Animal Welfare, Françoise Wemelsfelder

Animal Welfare Collection

This paper takes a closer look at the subjectivity/objectivity relationship, as it plays a role in the science of animal welfare. It argues that subjective, experiential states in animals such as well-being and suffering are, contrary to what is often assumed, open to empirical observation and scientific assessment. The presumably purely private, inaccessible nature of such states is not an inherent property of these states, but derives from their misguided conception as ‘causal objects’ in mechanistic models of behaviour. This inevitably endows subjective experience with a ‘hidden’ status. However, subjective experience should be approached on its own conceptual grounds, i.e. …

Development Of Piagetian Object Permanence In A Grey Parrot (Psittacus Erithacus), Irene M. Pepperberg, Mark R. Willner, Lauren B. Gravitz

Sentience Collection

The authors evaluated the ontogenetic performance of a grey parrot (Psittacus erithacus) on object permanence tasks designed for human infants. Testing began when the bird was 8 weeks old, prior to fledging and weaning. Because adult grey parrots understand complex invisible displacements (I. M. Pepperberg & F. A. Kozak, 1986), the authors continued weekly testing until the current subject completed all of I. C. Uzgiris and J. Hunt's (1975) Scale 1 tasks. Stage 6 object permanence with respect to these tasks emerged at 22 weeks, after the bird had fledged but before it was completely weaned. Although the parrot progressed …

Language-Naive Chimpanzees (Pan Troglodytes) Judge Relations Between Relations In A Conceptual Matching-To-Sample Task, Roger K.R. Thompson, David L. Oden, Sarah T. Boysen

Sentience Collection

Three chimpanzees with a history of conditional and numeric token training spontaneously matched relations between relations under conditions of nondifferential reinforcement. Heretofore, this conceptual ability was demonstrated only in language-trained chimpanzees. The performance levels of the language-naive animals in this study, however, were equivalent to those of a 4th animal—Sarah—whose history included language training and analogical problem solving. There was no evidence that associative factors mediated successful performance in any of the animals. Prior claims of a profound disparity between language-trained and language-naive chimpanzees apparently can be attributed to prior experience with arbitrary tokens consistently associated with abstract relations and …

The First Step In The Case For Great Ape Equality: The Argument For Other Minds, Kristin Andrews

Psychology Collection

No abstract provided.

Social Assemblages And Mating Relationships In Prairie Dogs: A Dna Fingerprint Analysis, Steven E. Travis, Con Slobodchikoff, Paul Kefan

Reproductive Behavior Collection

Mating system characterizations have been hindered by difficulties in accurately assigning parentage to offspring. We investigated the relationship between social assemblages and mating relationships in a territorial harem polygynous mammal, the Gunnison's prairie dog, using a combination of behavioral and molecular analyses. We demonstrate multiple paternity and an extraordinarily high incidence of extraterritorial fertilizations (i.e., 61% of all progeny), in combination with the existence of female kin groups. On this basis, we conclude that social assemblages alone provide a poor description of the Gunnison's prairie dog mating system, and suggest several potential reasons for the maintenance of territoriality in this …

Quantity-Based Interference And Symbolic Representations In Chimpanzees (Pan Troglodytes), S. T. Boysen, G. G. Berntson, M. B. Hannan, J. T. Cacioppo

Sentience Collection

Five chimpanzees with training in counting and numerical skills selected between 2 arrays of different amounts of candy or 2 Arabic numerals. A reversed reinforcement contingency was in effect, in which the selected array was removed and the subject received the nonselected candies (or the number of candies represented by the nonselected Arabic numeral). Animals were unable to maximize reward by selecting the smaller array when candies were used as array elements. When Arabic numerals were substituted for the candy arrays, all animals showed an immediate shift to a more optimal response strategy of selecting the smaller numeral, thereby receiving …

Taking Evolution Seriously: A Matter Of Primate Intelligence, Maxine Sheets-Johnstone

Intelligence Collection

No abstract provided.