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- Françoise Wemelsfelder, PhD (19)
- Marc Bekoff, PhD (19)
- Elodie Briefer, PhD (15)
- Lynne Sneddon, PhD (15)
- Sarah Boysen, PhD (15)
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- Culum Brown, PhD (14)
- Kristin Andrews, PhD (14)
- Jarrod Bailey, PhD (8)
- Con Slobodchikoff, PhD (6)
- John P. Gluck, PhD (6)
- Lori Marino, PhD (6)
- Martin Stephens, PhD (6)
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- Debra Durham, PhD (2)
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- Kenneth J. Shapiro, PhD (2)
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- Aaron P Blaisdell (1)
- Amanda Leonard, MA (1)
- Dara Wald (1)
- Elodie Briefer, Ph.D. (1)
- Lori Marino, Ph.D. (1)
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Articles 31 - 60 of 183
Full-Text Articles in Organisms
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
Marc Bekoff, PhD
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 …
Wild Justice And Fair Play: Cooperation, Forgiveness, And Morality In Animals, Marc Bekoff
Wild Justice And Fair Play: Cooperation, Forgiveness, And Morality In Animals, Marc Bekoff
Marc Bekoff, PhD
In this paper I argue that we can learn much about ‘wild justice’ and the evolutionary origins of social morality – behaving fairly – by studying social play behavior in group-living animals, and that interdisciplinary cooperation will help immensely. In our efforts to learn more about the evolution of morality we need to broaden our comparative research to include animals other than non-human primates. If one is a good Darwinian, it is premature to claim that only humans can be empathic and moral beings. By asking the question ‘What is it like to be another animal?’ we can discover rules …
Wild Justice Redux: What We Know About Social Justice In Animals And Why It Matters, Jessica Pierce, Marc Bekoff
Wild Justice Redux: What We Know About Social Justice In Animals And Why It Matters, Jessica Pierce, Marc Bekoff
Marc Bekoff, PhD
Social justice in animals is beginning to attract interest in a broad range of academic disciplines. Justice is an important area of study because it may help explain social dynamics among individuals living in tightly- knit groups, as well as social interactions among individuals who only occasionally meet. In this paper, we provide an overview of what is currently known about social justice in animals and offer an agenda for further research. We provide working definitions of key terms, outline some central research questions, and explore some of the challenges of studying social justice in animals, as well as the …
Aquatic Animals, Cognitive Ethology, And Ethics: Questions About Sentience And Other Troubling Issues That Lurk In Turbid Water, Marc Bekoff
Marc Bekoff, PhD
In this general, strongly pro-animal, and somewhat utopian and personal essay, I argue that we owe aquatic animals respect and moral consideration just as we owe respect and moral consideration to all other animal beings, regardless of the taxonomic group to which they belong. In many ways it is more difficult to convince some people of our ethical obligations to numerous aquatic animals because we do not identify or empathize with them as we do with animals with whom we are more familiar or to whom we are more closely related, including those species (usually terrestrial) to whom we refer …
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
Marc Bekoff, PhD
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 …
Animal Welfare And Individual Characteristics: A Conversation Against Speciesism, Marc Bekoff, Lori Gruen
Animal Welfare And Individual Characteristics: A Conversation Against Speciesism, Marc Bekoff, Lori Gruen
Marc Bekoff, PhD
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 …
Animal Minds, Cognitive Ethology, And Ethics, Colin Allen, Marc Bekoff
Animal Minds, Cognitive Ethology, And Ethics, Colin Allen, Marc Bekoff
Marc Bekoff, PhD
Our goal in this paper is to provide enough of an account of the origins of cognitive ethology and the controversy surrounding it to help ethicists to gauge for themselves how to balance skepticism and credulity about animal minds when communicating with scientists. We believe that ethicists’ arguments would benefit from better understanding of the historical roots of ongoing controversies. It is not appropriate to treat some widely reported results in animal cognition as if their interpretations are a matter of scientific consensus. It is especially important to understand why loose references to ‘‘cognitive ethology’’ by philosophers can signal ignorance …
Behavioral Ecology Of Coyotes: Social Organization, Rearing Patterns, Space Use, And Resource Defense, Marc Bekoff, Michael C. Wells
Behavioral Ecology Of Coyotes: Social Organization, Rearing Patterns, Space Use, And Resource Defense, Marc Bekoff, Michael C. Wells
Marc Bekoff, PhD
Two groups of coyotes in which genealogical relationships were known were studied in the Grand Teton National Park, outside of Jackson, Wyoming, U.S.A., from 1977-1982. One group, a pack consisting of parents and some non-dispersing and non-breeding offspring, defended a territory and the food (mainly elk carrion) contained within it, especially during winter, and also had helpers at den sites (5 of 6 were males). The other group, a mated resident pair, all of whose young dispersed during the first year of life, did not defend a territory and never had helpers at dens. Delayed dispersal and retention of some …
Minding Animals, Minding Earth: Science, Nature, Kinship, And Heart, Marc Bekoff
Minding Animals, Minding Earth: Science, Nature, Kinship, And Heart, Marc Bekoff
Marc Bekoff, PhD
This paper emphasizes the importance of broadening behavioral, ecological, and conservation science into a more integrative, interdisciplinary, socially responsible, compassionate, spiritual, and holistic endeavor.2,3 I will stress the significance of studies of animal behavior, especially ethological research concerned with animal emotions, in which individuals are named and recognized for their own personalities and temperaments, for helping us not only to learn about the nonhuman animal beings (hereafter animals) with whom we share Earth, but also for learning about who we are, our place in Nature, our humanness. We can be best understood in relationship to others. I will also develop …
Social Communication In Canids: Evidence For The Evolution Of A Stereotyped Mammalian Display, Marc Bekoff
Social Communication In Canids: Evidence For The Evolution Of A Stereotyped Mammalian Display, Marc Bekoff
Marc Bekoff, PhD
The variability in the duration and form of the canid play bow was studied in infant coyotes, wolves, wolf-dog hybrids, beagles, and adult free-ranging dogs. Both duration and form showed marked stereotypy. It appears that the role of this context-specific social signal in the communication of play intention has been fostered by selection for "morphological" stereotypy.
An Observational Study Of Coyote (Canis Latrans) Scent-Marking And Territoriality In Yellowstone National Park, Joseph J. Allen, Marc Bekoff, Robert L. Crabtree
An Observational Study Of Coyote (Canis Latrans) Scent-Marking And Territoriality In Yellowstone National Park, Joseph J. Allen, Marc Bekoff, Robert L. Crabtree
Marc Bekoff, PhD
Free-ranging coyotes (Canis latrans) living in neighboring packs were observed in the Lamar Valley of Yellowstone National Park, Wyoming, from Jan. to May 1997. Through direct observation, we recorded the location of coyote scent marks and information regarding the identity of the marking animal. Patterns of scent-marking were then analyzed spatially and demographically. All of the evidence from the present study supports a strong relationship between scent-marking and territoriality in these coyotes, and all predictions were met. A preponderance of scent marks was found in the periphery of territories. Most of those marks were raised-leg urinations (RLUs) and forward-lean urinations …
Social Ecology And Behavior Of Coyotes, Marc Bekoff, Michael C. Wells
Social Ecology And Behavior Of Coyotes, Marc Bekoff, Michael C. Wells
Marc Bekoff, PhD
Behavioral patterns are subject to natural selection and behavior like any other attributes of an animal, which contributes to individual survival. The chapter summarizes a long-term study of coyotes that was conducted in the Grand Teton National Park, in the northwest comer of Wyoming. There is remarkable agreement in the results stemming from a limited number of field projects concerned with the social behavior and behavioral ecology of coyotes, and some general principles concerning social ecology, scent marking, predatory behavior, time budgeting, and reproductive and care-giving patterns can be developed that are applicable not only to coyotes but to many …
The Development Of Social Interaction, Play, And Metacommunication In Mammals: An Ethological Perspective, Marc Bekoff
The Development Of Social Interaction, Play, And Metacommunication In Mammals: An Ethological Perspective, Marc Bekoff
Marc Bekoff, PhD
Analysis of the dynamics of the ontogeny of social interaction is of critical importance in order that behavioral development may be comprehended in its own right, and the relationship between infant and adult behavior understood. In this review, general concepts of behavioral development in mammals are discussed and analyzed, and the many variables that are involved are considered. When it is impossible to control or observe the social interaction of the developing organism in its natural environment, captive subjects should be used. There is increasing evidence that results obtained with the latter are related to social organization observed in the …
Reflections On Animal Selves, Marc Bekoff, Paul W. Sherman
Reflections On Animal Selves, Marc Bekoff, Paul W. Sherman
Marc Bekoff, PhD
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 …
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
Marc Bekoff, PhD
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 …
Naturalizing Anthropomorphism: Behavioral Prompts To Our Humanizing Of Animals, Alexandra C. Horowitz, Marc Bekoff
Naturalizing Anthropomorphism: Behavioral Prompts To Our Humanizing Of Animals, Alexandra C. Horowitz, Marc Bekoff
Marc Bekoff, PhD
Anthropomorphism is the use of human characteristics to describe or explain nonhuman animals. In the present paper, we propose a model for a unified study of such anthropomorphizing. We bring together previously disparate accounts of why and how we anthropomorphize and suggest a means to analyze anthropomorphizing behavior itself. We introduce an analysis of bouts of dyadic play between humans and a heavily anthropomorphized animal, the domestic dog. Four distinct patterns of social interaction recur in successful dog–human play: directed responses by one player to the other, indications of intent, mutual behaviors, and contingent activity. These findings serve as a …
Kin Recognition In Vertebrates: What Do We Really Know About Adaptive Value?, Andrew R. Blaustein, Marc Bekoff, John A. Byers, Thomas J. Daniels
Kin Recognition In Vertebrates: What Do We Really Know About Adaptive Value?, Andrew R. Blaustein, Marc Bekoff, John A. Byers, Thomas J. Daniels
Marc Bekoff, PhD
The ability of an animal to discriminate between kin and non-kin (kin recognition) has been the subject of numerous recent investigations. Grafen (Anim. Behav., 1990, 39, 42-54) recently reported that the evidence in support of kin recognition is weak and the data illustrating a preference for kin to associate in the laboratory may be more consistently explained as species recognition. It is suggested here, however, that in many cases it may be impossible to distinguish between species recognition and kin recognition, but in some cases, kin recognition seems apparent. It is also emphasized that very little is known about the …
Long-Term Effects Of Early Social Isolation In Macaca Mulatta: Changes In Dopamine Receptor Function Following Apomorphine Challenge, Mark H. Lewis, John P. Gluck, Tom L. Beauchamp, Michael F. Keresztury, Richard B. Mailman
Long-Term Effects Of Early Social Isolation In Macaca Mulatta: Changes In Dopamine Receptor Function Following Apomorphine Challenge, Mark H. Lewis, John P. Gluck, Tom L. Beauchamp, Michael F. Keresztury, Richard B. Mailman
John P. Gluck, PhD
The hypothesis that early social isolation results in long-term alterations in dopamine receptor sensitivity was tested using older adult rhesus monkeys. Isolated and control monkeys were challenged with apomorphine (0.1 and 0.3 mg/kg), and the drug effects on spontaneous blink rate, stereotyped behavior, and self-injurious behavior were quantified using observational measures. Monoamine metabolites were quantified from cisternal CSF by HPLC-EC, prior to pharmacological challenge. Isolated and control monkeys did not differ in CSF concentrations of HVA, 5-HIAA, or MHPG. At the higher dose, apomorphine significantly increased the rate of blinking, the occurrence of whole-body stereotypies, and the intensity of stereotyped …
Ethical Issues In The Use Of Animals In Biomedical And Psychopharmocological Research, John P. Gluck, Jordan Bell
Ethical Issues In The Use Of Animals In Biomedical And Psychopharmocological Research, John P. Gluck, Jordan Bell
John P. Gluck, PhD
Rationale: The ethical debate concerning the use of animals in biomedical and pharmacological research continues to be replete with misunderstandings about whether animals have moral standing. Objectives: This article briefly reviews the central ethical positions and their relationship to the basic parameters of research regulation from an international perspective. The issues associated with the validation of animal models will then be discussed. Finally, suggestions for empirical ethics research will be presented. Methods: Recent literature reviews were accessed and analyzed. Results: This review summarizes the pertinent ethical and research literature. Conclusions: In summary, regardless of the ethical perspective one favors, there …
Harry F. Harlow And Animal Research: Reflection On The Ethical Paradox, John P. Gluck
Harry F. Harlow And Animal Research: Reflection On The Ethical Paradox, John P. Gluck
John P. Gluck, PhD
With respect to the ethical debate about the treatment of animals in biomedical and behavioral research, Harry F. Harlow represents a paradox. On the one hand, his work on monkey cognition and social development fostered a view of the animals as having rich subjective lives filled with intention and emotion. On the other, he has been criticized for the conduct of research that seemed to ignore the ethical implications of his own discoveries. The basis of this contradiction is discussed and propositions for current research practice are presented.
Moving Beyond The Welfare Standard Of Psychological Well-Being For Nonhuman Primates: The Case Of Chimpanzees, John P. Gluck
Moving Beyond The Welfare Standard Of Psychological Well-Being For Nonhuman Primates: The Case Of Chimpanzees, John P. Gluck
John P. Gluck, PhD
Since 1985, the US Animal Welfare Act and Public Health Service policy have required that researchers using nonhuman primates in biomedical and behavioral research develop a plan ‘‘for a physical environment adequate to promote the psychological well-being of primates.’’ In pursuing this charge, housing attributes such as social companionship, opportunities to express species-typical behavior, suitable space for expanded locomotor activity, and nonstressful relationships with laboratory personnel are dimensions that have dominated the discussion. Regulators were careful not to direct a specific set of prescriptions (i.e., engineering standards) for the attainment of these goals, but to leave the design of the …
Social Deprivation Of Infant Rhesus Monkeys Alters The Chemoarchitecture Of The Brain: I. Subcortical Regions, Lee J. Martin, Dawn M. Spicer, Mark H. Lewis, John P. Gluck, Linda C. Cork
Social Deprivation Of Infant Rhesus Monkeys Alters The Chemoarchitecture Of The Brain: I. Subcortical Regions, Lee J. Martin, Dawn M. Spicer, Mark H. Lewis, John P. Gluck, Linda C. Cork
John P. Gluck, PhD
Rhesus monkeys (Macaca mulatta) reared during the first year of life without social contact develop persistent stereotyped movements, self-directed behaviors, and psychosocial abnormalities, but neurobiological mechanisms underlying the behaviors of socially deprived (SD) monkeys are unknown. Monkeys were reared in total social deprivation for the first 9 months of life; control monkeys were reared socially (SR) with mothers and peers. Subjects were killed at 19-24 yr of age. Because the behaviors of SD monkeys are reminiscent of changes in striatal or amygdalar function, we used immunocytochemistry for substance P (SP), leutine-enkephalin (LENK), somatostatin, calbindin, and tyrosine hydroxylase (TH) to evaluate …
Rethinking The Ethics Of Research Involving Nonhuman Animals: Introduction, Tom L. Beauchamp, Hope Ferdowsian, John P. Gluck
Rethinking The Ethics Of Research Involving Nonhuman Animals: Introduction, Tom L. Beauchamp, Hope Ferdowsian, John P. Gluck
John P. Gluck, PhD
No abstract provided.
Canis Lupus Cosmopolis: Wolves In A Cosmopolitan Worldview, William S. Lynn
Canis Lupus Cosmopolis: Wolves In A Cosmopolitan Worldview, William S. Lynn
William S. Lynn, PhD
The subject of wolf recovery in North America sparks heated controversy, both for and against. This paper explores how this subject is informed by cosmopolitan worldviews. These worldviews pull nature and culture into a common orbit of ethical meaning, with implications for the normative relationships that ought to pertain in landscapes shared by people and wolves. This theoretical outlook is illustrated using the controversy over wolves in the northeastern region of the United States. I conclude with a set of reflections on theorizing the cosmopolis, the interpretation of cosmopolitan landscapes, and living with cosmopolitan wolves.
Scale-Model Comprehension By Chimpanzees (Pan Troglodytes), Valerie A. Kuhlmeier, Sarah T. Boysen, Kimberly L. Mukobi
Scale-Model Comprehension By Chimpanzees (Pan Troglodytes), Valerie A. Kuhlmeier, Sarah T. Boysen, Kimberly L. Mukobi
Sarah Boysen, PhD
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 …
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
Sarah Boysen, PhD
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. …
Primate Numerical Competence: Contributions Toward Understanding Nonhuman Cognition, Sarah T. Boysen, Karen I. Hallberg
Primate Numerical Competence: Contributions Toward Understanding Nonhuman Cognition, Sarah T. Boysen, Karen I. Hallberg
Sarah Boysen, PhD
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 …
Emotional Engagements Predict And Enhance Social Cognition In Young Chimpanzees, Kim A. Bard, Roger Bakeman, Sarah T. Boysen, David A. Leavens
Emotional Engagements Predict And Enhance Social Cognition In Young Chimpanzees, Kim A. Bard, Roger Bakeman, Sarah T. Boysen, David A. Leavens
Sarah Boysen, PhD
Social cognition in infancy is evident in coordinated triadic engagements, that is, infants attending jointly with social partners and objects. Current evolutionary theories of primate social cognition tend to highlight species differences in cognition based on human-unique cooperative motives. We consider a developmental model in which engagement experiences produce differential outcomes. We conducted a 10-year-long study in which two groups of laboratory-raised chimpanzee infants were given quantifiably different engagement experiences. Joint attention, cooperativeness, affect, and different levels of cognition were measured in 5- to 12-month-old chimpanzees, and compared to outcomes derived from a normative human database. We found that joint …
Visual Attention And Its Relation To Knowledge States In Chimpanzees, Pan Troglodytes, Megan J. Bulloch, Sarah T. Boysen, Ellen E. Furlong
Visual Attention And Its Relation To Knowledge States In Chimpanzees, Pan Troglodytes, Megan J. Bulloch, Sarah T. Boysen, Ellen E. Furlong
Sarah Boysen, PhD
Primates rely on visual attention to gather knowledge about their environment. The ability to recognize such knowledge-acquisition activity in another may demonstrate one aspect of Theory of Mind. Using a series of experiments in which chimpanzees were presented with a choice between an experimenter whose visual attention was available and another whose vision was occluded, we asked whether chimpanzees understood the relationship between visual attention and knowledge states. The animals showed sophisticated understanding of attention from the first presentation of each task. Under more complex experimental conditions, the subjects had more difficulty with species-typical processing of attentional cues and those …
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
Sarah Boysen, PhD
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 …