Open Access. Powered by Scholars. Published by Universities.®

Animal Studies Commons™

Open Access. Powered by Scholars. Published by Universities.®

Psychology

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 571 - 600 of 679

Full-Text Articles in Animal Studies

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 Oct 1998

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 PO2. 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 Jan 1998

‘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 Jan 1998

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 …


Why It Is Important To Understand Animal Behavior, Joy Mench Jan 1998

Why It Is Important To Understand Animal Behavior, Joy Mench

Anthropomorphism and Anthropocentrism Collection

Although people have long been fascinated by the behavior of animals, the formal discipline of animal behavior--ethology--is actually relatively new, dating to the work of Konrad Lorenz in Austria in the 1930s. Application of ethological principles and methods to the study of animal welfare is an even newer endeavor, of course, and one that has generated a great deal of stimulating discussion and controversy during its short history. In this paper, I provide an overview of the development of behavioral approaches to the study of animal welfare. I then discuss some reasons that behaviors are important to animals and describe …


Farrowing Behaviour And Stillbirth In Two Environments: An Evaluation Of The Restraint-Stillbirth Hypothesis, D. Fraser, P. A. Phillips, B. K. Thompson Dec 1997

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 Oct 1997

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 Aug 1997

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 Jul 1997

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 May 1997

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 Mar 1997

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 Jan 1997

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 Aug 1996

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 Apr 1996

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 Jan 1996

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 Jan 1996

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

Intelligence Collection

No abstract provided.


Mirror Use By African Grey Parrots (Psittacus Erithacus), Irene M. Pepperberg, Sean E. Garcia, Eric C. Jackson, Sharon Marconi Jun 1995

Mirror Use By African Grey Parrots (Psittacus Erithacus), Irene M. Pepperberg, Sean E. Garcia, Eric C. Jackson, Sharon Marconi

Sentience Collection

No abstract provided.


Indicating Acts During Counting By A Chimpanzee (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson, Traci A. Shreyer, Michelle B. Hannan Mar 1995

Indicating Acts During Counting By A Chimpanzee (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson, Traci A. Shreyer, Michelle B. Hannan

Sentience Collection

A chimpanzee (Pan troglodytes) experienced in counting arrays of 0-7 items and trained for comprehension of number symbols, spontaneously displayed a variety of indicating acts (e.g., pointing, touching, and rearranging items) during counting. Twenty-five sessions were videotaped, and all trials were evaluated for the relations among number of items presented, number of indicating acts displayed, and the Arabic number selected to represent the array. Significant correlations included the relations between number of items and the cardinal number selected by the animal, between the number of items and indicating acts displayed by the chimpanzee, and between the number of indicating acts …


Science, Values And Animal Welfare: Exploring The ‘Inextricable Connection’, D. Fraser Jan 1995

Science, Values And Animal Welfare: Exploring The ‘Inextricable Connection’, D. Fraser

Animal Welfare Collection

In conceptualizing animal welfare, it is useful to distinguish among three types of concepts. 'Type l' are single, measurable attributes. 'Type 2' are single attributes that cannot be measured directly but can be estimated by correctly combining various contributing attributes. 'Type 3' are concepts involving multiple attributes which are grouped together because they serve some common function, and whose relative importance cannot be established in an entirely objective way. Individuals who treat animal welfare as a type 1 concept may propose single, objective measures of welfare, such as longevity or levels of stress-related hormones; however, this approach rests on judgements, …


Comprehension Of Cause-Effect Relations In A Tool-Using Task By Chimpanzees (Pan Troglodytes), Luca Limongelli, Sarah T. Boysen, Elisabetta Visalberghi Jan 1995

Comprehension Of Cause-Effect Relations In A Tool-Using Task By Chimpanzees (Pan Troglodytes), Luca Limongelli, Sarah T. Boysen, Elisabetta Visalberghi

Sentience Collection

Five chimpanzees (Pan troglodytes) were tested to assess their understanding of causality in a tool task. The task consisted of a transparent tube with a trap-hole drilled in its middle. A reward was randomly placed on either side of the hole. Depending on which side the chimpanzee inserted the stick into, the candy was either pushed out of the tube or into the trap. In Experiment 1, the success rate of 2 chimpanzees rose highly above chance, but that of the other subjects did not. Results show that the 2 successful chimpanzees selected the correct side for insertion beforehand. Experiment …


Responses To Quantity: Perceptual Versus Cognitive Mechanisms In Chimpanzees (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson Jan 1995

Responses To Quantity: Perceptual Versus Cognitive Mechanisms In Chimpanzees (Pan Troglodytes), Sarah T. Boysen, Gary G. Berntson

Sentience Collection

Two chimpanzees were trained to select among 2 different amounts of candy (1-6 items). The task was designed so that selection of either array by the active (selector) chimpanzee resulted in that array being given to the passive (observer) animal, with the remaining (nonselected) array going to the selector. Neither animal was able to select consistently the smaller array, which would reap the larger reward. Rather, both animals preferentially selected the larger array, thereby receiving the smaller number of reinforcers. When Arabic numerals were substituted for the food arrays, however, the selector animal evidenced more optimal performance, immediately selecting the …


Play Signals As Punctuation: The Structure Of Social Play In Canids, Marc Bekoff Jan 1995

Play Signals As Punctuation: The Structure Of Social Play In Canids, Marc Bekoff

Ethology Collection

Actions called play signals have evolved in many species in which social play has been observed. Despite there being only few empirical demonstrations, it generally is accepted that play signals are important in the initiation ("I want to play") and maintenance ("I still want to play") of ongoing social play. In this study I consider whether a specific and highly stereotyped signal, the bow, is used to maintain social play in adult and infant domestic dogs, infant wolves, and infant coyotes.

To answer this question the temporal placement of bows relative to actions that are also used in other contexts …


Vigilance, Flock Size, And Flock Geometry: Information Gathering By Western Evening Grosbeaks (Aves, Fringillidae), Marc Bekoff Jan 1995

Vigilance, Flock Size, And Flock Geometry: Information Gathering By Western Evening Grosbeaks (Aves, Fringillidae), Marc Bekoff

Ethology Collection

Vigilance (scanning) and other behavior patterns were studied in free-ranging Evening Grosbeaks (Coccothraustes vespertinus) at feeders to assess how flock size and flock geometry influenced the behavior of individual birds. The present results indicate that the way in which individual grosbeaks are positioned with respect to one another effects many aspects of their behavior, especially when a flock contains four or more birds. Birds in a linear array who have difficulty seeing one another, when compared to individuals organized in a circle who can easily see one another, are (1) more vigilant, (2) change their head and body positions more …


Calling By Domestic Piglets: Reliable Signals Of Need?, Daniel M. Weary, David Fraser Jan 1995

Calling By Domestic Piglets: Reliable Signals Of Need?, Daniel M. Weary, David Fraser

Communication Skills Collection

Two manipulations were performed on domestic piglets to determine whether differences in calling during periods of separation from the mother can indicate differences in need. In both cases, the aim was to manipulate the piglet's need for the sow's attention. In the first manipulation a 'thriving' piglet (i.e. the piglet with the heaviest weight and most rapid weight gain) and a 'non-thriving' one (lightest and slowest weight gain) were selected from each of 15 litters. The two piglets were removed from the sow and litter and recorded for 13 min in separate isolated enclosures. For the second manipulation, two piglets …


Vocal Learning In Grey Parrots (Psittacus Erithacus): Effects Of Social Interaction, Reference, And Context, Irene M. Pepperberg Apr 1994

Vocal Learning In Grey Parrots (Psittacus Erithacus): Effects Of Social Interaction, Reference, And Context, Irene M. Pepperberg

Sentience Collection

For many passerines, the extent,timing, and even presence of allospecific vocal learning can be influenced by the form of input that is received. Little data exist, however, on vocal learning in parrots (Psittacidae). I have previously proposed that such vocal learning proceeds most readily when input is (1) referential, (2) contextually applicable, and (3) interactive. The referential aspect demonstrates the meaning of the code to be taught, the contextual aspect demonstrates the use that can be made of the information contained in the code, and the interactive aspect provides explicit training that is constantly adjusted to the level of the …


Numerical Competence In An African Gray Parrot (Psittacus Erithacus), Irene M. Pepperberg Mar 1994

Numerical Competence In An African Gray Parrot (Psittacus Erithacus), Irene M. Pepperberg

Sentience Collection

An African gray parrot (Psittacus erithacus), Alex, trained to label vocally collections of 1-6 simultaneously presented homogeneous objects, correctly identified, without further training, quantities of targeted subsets in heterogeneous collections. For each test trial Alex was shown different collections of 4 groups of items that varied in 2 colors and 2 object categories (e.g., blue and red keys and trucks) and was asked to label the number of items uniquely defined by the conjunction of 1 color and 1 object category (e.g., "How many blue key?"). The collections were designed to provide maximal confounds (or distractions) and thus replicate the …


The Relationship Between Creep Feeding Behavior Of Piglets And Adaptation To Weaning: Effect Of Diet Quality, David Fraser, J. J.R. Feddes, E. A. Pajor Mar 1994

The Relationship Between Creep Feeding Behavior Of Piglets And Adaptation To Weaning: Effect Of Diet Quality, David Fraser, J. J.R. Feddes, E. A. Pajor

Feeding Behavior Collection

Individual variation in creep feed intake and its relation to adaptation to weaning were studied in piglets weaned at 4 wk of age. The animals received either a "low-complexity" creep-starter diet based on corn, barley and soybean meal (12 litters), or a "high-complexity", medicated, commercial diet without soybean meal (12 litters). Diets were fed as creep feed during the 2 wk before weaning, and as the sole diet during the 2 wk after weaning. Creep feeding behavior of piglets was monitored by video recording. Pigs fed the high-complexity diet consumed more creep feed (P < 0.05), tended to gain more during the week before weaning (P < 0.10), and converted feed more efficiently and gained more weight in the 2 wk after weaning (P < 0.01). Use of creep feed varied greatly among individual littermates. Multiple regression analysis showed that on the high-complexity diet, pigs that used creep feed more than their littermates tended to be those with low gains in weeks 1-3 after birth (P < 0.001), and tended to gain more weight during the week before and during the 2 wk after weaning (P < 0.01). The trends were consistent but weaker with the low-complexity diet. However, predictive power was low, with creep feeding accounting for only 4% of individual variation in post-weaning gain on the high-complexity diet and 1% on the low. Regardless of diet quality, therefore, creep feeding remained highly variable and only weakly related to weight gains during the 2 wk after weaning.


Individual Differences In The Cognitive Abilities Of Chimpanzees, Sarah T. Boysen Jan 1994

Individual Differences In The Cognitive Abilities Of Chimpanzees, Sarah T. Boysen

Psychology Collection

No abstract provided.


Vocal Perception: Brain Event-Related Potentials In A Chimpanzee, Gary G. Berntson, Sarah T. Boysen, Michael W. Torello Sep 1993

Vocal Perception: Brain Event-Related Potentials In A Chimpanzee, Gary G. Berntson, Sarah T. Boysen, Michael W. Torello

Sentience Collection

We describe the first brain event-related potential (ERP) study of cognitive processes in the chimpanzee. In an extension of our studies on the ontogeny of vocal perception, ERP measures were obtained during the presentation of simple nonsignal stimuli as well as conspecific and human vocalizations. We initially confirmed findings from humans and monkeys of the appearance of a long-latency positivity in the ERP waveform to a rare stimulus in an oddball paradigm. This ERP component is reminiscent of the P3a reported in humans under similar (passive) experimental conditions. We further demonstrated that both conspecific and human vocal stimuli having affective …


Animal Welfare And Individual Characteristics: A Conversation Against Speciesism, Marc Bekoff, Lori Gruen Jan 1993

Animal Welfare And Individual Characteristics: A Conversation Against Speciesism, Marc Bekoff, Lori Gruen

Animal Welfare Collection

It seems impossible for a human being not to have some point of view concerning nonhuman animal (hereafter animal) welfare. Many people make decisions about how humans are permitted to treat animals using speciesist criteria, basing their decisions on an individual's species membership rather than on that animal's individual characteristics. Although speciesism provides a convenient way for making difficult decisions about who should be used in different types of research, we argue that such decisions should rely on an analysis of individual characteristics and should not be based merely on species membership. We do not argue that the concept of …


Counting In Chimpanzees: Nonhuman Principles And Emergent Properties Of Number, Sarah T. Boysen Jan 1993

Counting In Chimpanzees: Nonhuman Principles And Emergent Properties Of Number, Sarah T. Boysen

Numeracy Collection

No abstract provided.